141 results on '"Yinan Wei"'
Search Results
2. Probing the Dynamics of AcrB Through Disulfide Bond Formation
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Prasangi Rajapaksha, Ankit Pandeya, and Yinan Wei
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Chemistry ,QD1-999 - Published
- 2020
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3. Automatic segmentation of arterial tree from 3D computed tomographic pulmonary angiography (CTPA) scans
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Chi Zhang, Mingxia Sun, Yinan Wei, Haoyuan Zhang, Sheng Xie, and Tongxi Liu
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Pulmonary artery segmentation ,3D vessel enhancement ,fuzzy connectedness ,pulmonary embolism ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Surgery ,RD1-811 - Abstract
Pulmonary embolism (PE) and other pulmonary vascular diseases, have been found associated with the changes in arterial morphology. To detect arterial changes, we propose a novel, fully automatic method that can extract pulmonary arterial tree in computed tomographic pulmonary angiography (CTPA) images. The approach is based on the fuzzy connectedness framework, combined with 3D vessel enhancement and Harris Corner detection to achieve accurate segmentation. The effectiveness and robustness of the method is validated in clinical datasets consisting of 10 CT angiography scans (6 without PE and 4 with PE). The performance of our method is compared with manual classification and machine learning method based on random forest. Our method achieves a mean accuracy of 92% when compared to manual reference, which is higher than the 89% accuracy achieved by machine learning. This performance of the segmentation for pulmonary arteries may provide a basis for the CAD application of PE.
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- 2019
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4. Extracellular Histones Trigger Disseminated Intravascular Coagulation by Lytic Cell Death
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Yan Zhang, Congqing Wu, Lan Li, Ankit Pandeya, Guoying Zhang, Jian Cui, Daniel Kirchhofer, Jeremy P. Wood, Susan S. Smyth, Yinan Wei, and Zhenyu Li
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platelet ,thrombocytopenia ,histones ,DIC ,tissue factor ,coagulation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Histones are cationic nuclear proteins that are essential for the structure and functions of eukaryotic chromatin. However, extracellular histones trigger inflammatory responses and contribute to death in sepsis by unknown mechanisms. We recently reported that inflammasome activation and pyroptosis trigger coagulation activation through a tissue-factor (TF)-dependent mechanism. We used a combination of various deficient mice to elucidate the molecular mechanism of histone-induced coagulation. We showed that histones trigger coagulation activation in vivo, as evidenced by coagulation parameters and fibrin deposition in tissues. However, histone-induced coagulopathy was neither dependent on intracellular inflammasome pathways involving caspase 1/11 and gasdermin D (GSDMD), nor on cell surface receptor TLR2- and TLR4-mediated host immune response, as the deficiency of these genes in mice did not protect against histone-induced coagulopathy. The incubation of histones with macrophages induced lytic cell death and phosphatidylserine (PS) exposure, which is required for TF activity, a key initiator of coagulation. The neutralization of TF diminished the histone-induced coagulation. Our findings revealed lytic cell death as a novel mechanism of histone-induced coagulation activation and thrombosis.
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- 2022
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5. Comparison of in vitro and in vivo oligomeric states of a wild type and mutant trimeric inner membrane multidrug transporter
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Zhaoshuai Wang, Wei Lu, Prasangi Rajapaksha, Thomas Wilkop, Yuguang Cai, and Yinan Wei
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Biology (General) ,QH301-705.5 ,Biochemistry ,QD415-436 - Abstract
Many membrane proteins exist and function as oligomers or protein complexes. Routine analytical methods involve extraction and solubilization of the proteins with detergents, which could disturb their actual oligomeric state. AcrB is a trimeric inner membrane multidrug transporter in E. coli. In previous studies, we created a mutant AcrBP223G, which behaves like a monomer when extracted from the cell membrane. However, the actual oligomeric state of AcrBP223G in cell membranes remained unclear, which complicated the interpretation of the mechanism by which the mutation affects function. Here we used several complementary methods to determine the oligomeric state of AcrBP223G in E. coli cell membranes. Two sets of quantitative fluorescent techniques were exploited. For these, we created fluorescent tagged AcrB, AcrB-CFP and AcrB-YPet. Fluorescence resonance energy transfer (FRET) and fluorescence recovery after photobleaching (FRAP) were employed to characterize independently the efficiency of energy transfer between co-expressed AcrB-CFP and AcrB-YPet, and the diffusion coefficient of AcrB-YPet and AcrBP223G-YPet in live E. coli cells. Second, we introduced Cys pairs at the inter-subunit interface and used controlled oxidation to probe inter-subunit distances. The results from all studies converge on the conclusion that AcrBP223G exists as a trimer in cell membranes, which dissociates during the purification steps. The small change in trimer affinity and structure leads to a significant loss of AcrB activity. In addition, throughout this study we developed protocols and established benchmark values, useful for further studies on membrane protein associations in cell membranes. Keywords: FRET, FRAP, Disulfide trapping, Membrane protein oligomer, Cell membrane, AcrB diffusion coefficient
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- 2018
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6. Data on spectrum-based fluorescence resonance energy transfer measurement of E. coli multidrug transporter AcrB
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Yuguang Cai, Thomas Wilkop, and Yinan Wei
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Science (General) ,Q1-390 - Abstract
This paper presented the dataset of correction parameters used in the determination of the energy transfer efficiencies from the spectrum-based fluorescence resonance energy transfer (FRET) measurement in a trimeric membrane protein AcrB. The cyan fluorescent protein (CFP) and yellow fluorescent protein (YPet) were used as the donor and acceptor, respectively. Two AcrB fusion proteins were constructed, AcrB-CFP and AcrB-YPet. The proteins were co-expressed in Escherichia coli cells, and energy transfer efficiency were determined in live cells. To obtain reliable energy transfer data, a complete set of correction parameters need to be first determined to accommodate for factors such as background fluorescence and spectra overlap. This paper described the methodology and determination of the correction factors, which are useful data and reference points for researchers working on fluorescence measurement of membrane protein complexes in live bacteria cells. Further interpretation and discussion of these data can be found in “Comparison of in vitro and in vivo oligomeric states of a wild type and mutant trimeric inner membrane multidrug transporter” (Wang et al., in press).
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- 2018
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7. Biotinylation as a tool to enhance the uptake of small molecules in Gram-negative bacteria
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Ankit Pandeya, Ling Yang, Olaniyi Alegun, Chamikara Karunasena, Chad Risko, Zhenyu Li, and Yinan Wei
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Medicine ,Science - Abstract
Antibiotic resistance is a major public health concern. The shrinking selection of effective antibiotics and lack of new development is making the situation worse. Gram-negative bacteria more specifically pose serious threat because of their double layered cell envelope and effective efflux systems, which is a challenge for drugs to penetrate. One promising approach to breach this barrier is the “Trojan horse strategy”. In this technique, an antibiotic molecule is conjugated with a nutrient molecule that helps the antibiotic to enter the cell through dedicated transporters for the nutrient. Here, we explored the approach using biotin conjugation with a florescent molecule Atto565 to determine if biotinylation enhances accumulation. Biotin is an essential vitamin for bacteria and is obtained through either synthesis or uptake from the environment. We found that biotinylation enhanced accumulation of Atto565 in E. coli. However, the enhancement did not seem to be due to uptake through biotin transporters since the presence of free biotin had no observable impact on accumulation. Accumulated compound was mostly in the periplasm, as determined by cell fractionation studies. This was further confirmed through the observation that expression of streptavidin in the periplasm specifically enhanced the accumulation of biotinylated Atto565. This enhancement was not observed when streptavidin was expressed in the cytoplasm indicating no significant distribution of the compound inside the cytoplasm. Using gene knockout strains, plasmid complementation and mutagenesis studies we demonstrated that biotinylation made the compound a better passenger through OmpC, an outer membrane porin. Density functional theory (DFT)-based evaluation of the three-dimensional geometries showed that biotinylation did not directly stabilize the conformation of the compound to make it favorable for the entry through a pore. Further studies including molecular dynamics simulations are necessary to determine the possible mechanisms of enhanced accumulation of the biotinylated Atto565.
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- 2021
8. Distribution of fluoroquinolones in the two aqueous compartments of Escherichia coli
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Ankit Pandeya, Olaniyi Alegun, Yuguang Cai, and Yinan Wei
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Gram-negative bacteria ,Periplasm accumulation ,Fluoroquinolone ,Minimum inhibitory concentration ,Biology (General) ,QH301-705.5 ,Biochemistry ,QD415-436 - Abstract
The double-layered cell envelope of Gram-negative bacteria and active drug efflux present a formidable barrier for antimicrobial compounds to penetrate. Fluoroquinolones are among the few classes of antimicrobials that are clinically useful in the treatment of Gram-negative bacterial infection. Previous studies on fluoroquinolone accumulation measured total bacteria associated compounds, rather than the cytoplasmic accumulation. Fluoroquinolones target the type II topoisomerases in the cytoplasm. Thus, the cytoplasmic accumulation is expected to be more relevant to the potency of the drugs. Here, we fractionated and measured the concentration of nine fluoroquinolone compounds in the periplasm and the cytoplasm of two strains of E. coli cells, a parent strain and its isogenic efflux-deficient tolC knockout strain. The potency of the drugs was determined using the minimum inhibitory concentration (MIC) assay. We found that all fluoroquinolones tested accumulated at much higher concentrations in the periplasm than in the cytoplasm. The periplasmic concentrations were 2–15 folds higher than the cytoplasmic concentration, while the actual distribution ratio varies drastically among the compounds tested. Good correlation between the MIC and the cytoplasmic accumulation, but not whole cell accumulation, was observed using a pair of isogenic wild type and drug-efflux deficient strains.
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- 2020
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9. Role of Protein Charge Density on Hepatitis B Virus Capsid Formation
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Xinyu Sun, Dong Li, Zhaoshuai Wang, Panchao Yin, Rundong Hu, Hui Li, Qiao Liu, Yunyi Gao, Baiping Ren, Jie Zheng, Yinan Wei, and Tianbo Liu
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Chemistry ,QD1-999 - Published
- 2018
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10. Insight into the AcrAB-TolC Complex Assembly Process Learned from Competition Studies
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Prasangi Rajapaksha, Isoiza Ojo, Ling Yang, Ankit Pandeya, Thilini Abeywansha, and Yinan Wei
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RND pump ,dominant negative effect ,assembly ,protein-protein interaction ,mutation ,Therapeutics. Pharmacology ,RM1-950 - Abstract
The RND family efflux pump AcrAB-TolC in E. coli and its homologs in other Gram-negative bacteria are major players in conferring multidrug resistance to the cells. While the structure of the pump complex has been elucidated with ever-increasing resolution through crystallography and Cryo-EM efforts, the dynamic assembly process remains poorly understood. Here, we tested the effect of overexpressing functionally defective pump components in wild type E. coli cells to probe the pump assembly process. Incorporation of a defective component is expected to reduce the efflux efficiency of the complex, leading to the so called “dominant negative” effect. Being one of the most intensively studied bacterial multidrug efflux pumps, many AcrA and AcrB mutations have been reported that disrupt efflux through different mechanisms. We examined five groups of AcrB and AcrA mutants, defective in different aspects of assembly and substrate efflux. We found that none of them demonstrated the expected dominant negative effect, even when expressed at concentrations many folds higher than their genomic counterpart. The assembly of the AcrAB-TolC complex appears to have a proof-read mechanism that effectively eliminated the formation of futile pump complex.
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- 2021
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11. Donnan Potential across the Outer Membrane of Gram-Negative Bacteria and Its Effect on the Permeability of Antibiotics
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Olaniyi Alegun, Ankit Pandeya, Jian Cui, Isoiza Ojo, and Yinan Wei
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Donnan potential ,Gram-negative bacteria ,antibiotics ,membrane permeability ,cellular accumulation ,Therapeutics. Pharmacology ,RM1-950 - Abstract
The cell envelope structure of Gram-negative bacteria is unique, composed of two lipid bilayer membranes and an aqueous periplasmic space sandwiched in between. The outer membrane constitutes an extra barrier to limit the exchange of molecules between the cells and the exterior environment. Donnan potential is a membrane potential across the outer membrane, resulted from the selective permeability of the membrane, which plays a pivotal role in the permeability of many antibiotics. In this review, we discussed factors that affect the intensity of the Donnan potential, including the osmotic strength and pH of the external media, the osmoregulated periplasmic glucans trapped in the periplasmic space, and the displacement of cell surface charges. The focus of our discussion is the impact of Donnan potential on the cellular permeability of selected antibiotics including fluoroquinolones, tetracyclines, β-lactams, and trimethoprim.
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- 2021
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12. Dual-Functional-Tag-Facilitated Protein Labeling and Immobilization
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Xinyi Zhang, Wei Lu, Kevin Kwan, Dibakar Bhattacharyya, and Yinan Wei
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Chemistry ,QD1-999 - Published
- 2017
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13. Preliminary Study of MR Diffusion Tensor Imaging of the Liver for the Diagnosis of Hepatocellular Carcinoma.
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Xinghui Li, Qi Liang, Ling Zhuang, Xiaoming Zhang, Tianwu Chen, Liangjun Li, Jun Liu, Horea Calimente, Yinan Wei, and Jiani Hu
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Medicine ,Science - Abstract
To evaluate the feasibility of differentiating between hepatocellular carcinomas (HCC) and healthy liver using diffusion tensor imaging (DTI).All subjects underwent an abdominal examination on a 3.0T MRI scanner. Two radiologists independently scored the image quality (IQ). An optimal set of DTI parameters was obtained from a group of fifteen volunteers with multiple b-values (100, 300, 500, and 800 s/mm2) and various diffusion-encoding directions (NED = 6, 9, and 12)using two way ANOVA analysis. Eighteen Patients with HCC underwent DTI scans with the optimized parameters. Fractional anisotropy(FA) and average apparent diffusion coefficient (ADC) values were measured. The differences of FA and ADC values between liver healthy region and HCC lesion were compared through paired t tests.There were no significant changes in liver IQ and FA/ADC values with increased NED(P >0.05), whereas the liver IQ and FA/ADC values decreased significantly with increased b-values(P
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- 2015
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14. Functional relevance of AcrB Trimerization in pump assembly and substrate binding.
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Wei Lu, Meng Zhong, Qian Chai, Zhaoshuai Wang, Linliang Yu, and Yinan Wei
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Medicine ,Science - Abstract
AcrB is a multidrug transporter in the inner membrane of Escherichia coli. It is an obligate homotrimer and forms a tripartite efflux complex with AcrA and TolC. AcrB is the engine of the efflux machinery and determines substrate specificity. Active efflux depends on several functional features including proton translocation across the inner membrane through a proton relay pathway in the transmembrane domain of AcrB; substrate binding and migration through the substrate translocation pathway; the interaction of AcrB with AcrA and TolC; and the formation of AcrB homotrimer. Here we investigated two aspects of the inter-correlation between these functional features, the dependence of AcrA-AcrB interaction on AcrB trimerization, and the reliance of substrate binding and penetration on protein-protein interaction. Interaction between AcrA and AcrB was investigated through chemical crosslinking, and a previously established in vivo fluorescent labeling method was used to probe substrate binding. Our data suggested that dissociation of the AcrB trimer drastically decreased its interaction with AcrA. In addition, while substrate binding with AcrB seemed to be irrelevant to the presence or absence of AcrA and TolC, the capability of trimerization and conduction of proton influx did affect substrate binding at selected sites along the substrate translocation pathway in AcrB.
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- 2014
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15. AcrB trimer stability and efflux activity, insight from mutagenesis studies.
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Linliang Yu, Wei Lu, and Yinan Wei
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Medicine ,Science - Abstract
The multidrug transporter AcrB in Escherichia coli exists and functions as a homo-trimer. The assembly process of obligate membrane protein oligomers, including AcrB, remains poorly understood. In a previous study, we have shown that individual AcrB subunit is capable of folding independently, suggesting that trimerization of AcrB follows a three-stage pathway in which monomers first fold, and then assemble. Here we destabilized the AcrB trimer through mutating a single Pro (P223) in the protruding loop of AcrB, which drastically reduced the protein activity. We replaced P223 separately with five residues, including Ala, Val, Tyr, Asn, and Gly, and found that AcrB(P223G) was the least active. Detailed characterization of AcrB(P223G) revealed that the protein existed as a well-folded monomer after purification, but formed a trimer in vivo. The function of the mutant could be partly restored through strengthening the stability of the trimer using an inter-subunit disulfide bond. Our results also suggested that the protruding loop is well structured during AcrB assembly with P223 served as a "wedge" close to the tip to stabilize the AcrB trimer structure. When this wedge is disrupted, the stability of the trimer is reduced, accompanied by a decrease of drug efflux activity.
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- 2011
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16. A monoadduct generating Ru(<scp>ii</scp>) complex induces ribosome biogenesis stress and is a molecular mimic of phenanthriplatin
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Richard J. Mitchell, Sarah M. Kriger, Alexander D. Fenton, Dmytro Havrylyuk, Ankit Pandeya, Yang Sun, Tami Smith, Jason E. DeRouchey, Jason M. Unrine, Viral Oza, Jessica S. Blackburn, Yinan Wei, David K. Heidary, and Edith C. Glazer
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Chemistry (miscellaneous) ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Molecular Biology ,Biochemistry - Abstract
Phenanthriplatin forms DNA mono-adducts and induces ribosome biogenesis stress. Using a semi-rational strategy, Ru(ii) complexes were created that act as biological mimics of phenanthriplatin with improved properties.
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- 2023
17. Abstract 487: Extracellularhistonestrigger Disseminated Intravascular Coagulation By Lytic Cell Death
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Congqing Wu, Yan Zhang, Lan Li, Ankit Pandeya, Guoying Zhang, Jian Cui, Daniel Kirchhofer, Jeremy P Wood, Susan S Smyth, Yinan Wei, and Zhenyu Li
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Cardiology and Cardiovascular Medicine - Abstract
Background: Histones are cationic nuclear proteins that are essential for the structure andfunctions of eukaryotic chromatin. However, extracellular histones trigger inflammatoryresponses and contribute to death in sepsis by unknown mechanisms. We recently reported thatinflammasome activation and pyroptosis trigger coagulation activation through a tissue factor(TF)-dependent mechanism. Objective and methods: We used a combination of various deficient mice to elucidate the molec-ular mechanism of histone-induced coagulation. Results: We show that histones trigger coagulation activation in vivo as evidenced bycoagulation parameters and fibrin deposition in tissues. However, histone-induced coagulopathywas neither dependent on intracelluar inflammasome pathwyas involving caspase 1/11 andgasdermin D (GSDMD), nor on cell surface TLR2 and TLR4 mediated host immune response, asdeficiency of these genes in mice did not protect against histone-induced coagulopathy.Incubation of histones with macrophages induced lytic cell death and phosphatidylserine (PS)exposure, which is required for TF activity, a key initiator of coagulation. Neutralization of TFdiminished histone-induced coagulation. Conclusion: Our findings reveal lytic cell death as a novel mechanism of histone-inducecoagulation activation and thrombosis.
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- 2022
18. Synthesis and biological evaluation of<scp>stilbene‐based</scp>peptoid mimics against the phytopathogenic bacteriumXanthomonas citripv.citri
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Jianbo Shuai, Xingdong Lin, Jianqing Hu, Yan Li, Daohang He, and Yinan Wei
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0106 biological sciences ,Citrus ,Xanthomonas ,Antimicrobial peptides ,medicine.disease_cause ,01 natural sciences ,Xanthomonas citri ,Peptoids ,chemistry.chemical_compound ,Minimum inhibitory concentration ,Stilbenes ,medicine ,Bioassay ,Plant Diseases ,Biological Products ,Bacteria ,Chemistry ,Peptoid ,Pathogenic bacteria ,General Medicine ,010602 entomology ,Biochemistry ,Insect Science ,Citrus canker ,Antibacterial activity ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Background The emergence of drug-resistant phytopathogenic bacteria and the need for new type of biological disease-control agents have accelerated efforts toward searching for alternative candidates with a low propensity for resistance development. In this study, a new series of stilbene-based peptoid mimics were synthesized, and their biological activities were evaluated against citrus pathogenic bacteria in vitro and in vivo. Results Antibacterial bioassay results showed that the dicationic peptoid mimics 9a and 9b displayed excellent bioactivity against Xanthomonas axonopodis pv citri, with the minimum inhibitory concentration (MIC) values of 25 μM, which were superior to those of commercial copper biocides Delite (200 μM) and Kasumin Bordeaux (100 μM). In vivo bioassay further confirmed their control efficacy against plant bacterial diseases. In addition, the antibacterial mechanism of action elucidated their membrane-disruption effects resulting in the leakage of the bacterial membranes, which was similar to that of antimicrobial peptides (AMPs). Moreover, the inhibition effect on biofilm formation of peptoid mimics has also been demonstrated. Conclusion Stilbene-based peptoid mimics synthesized in this study showed promising antibacterial activity with a potent membrane-disruptive mechanism. The results suggested that stilbene-based peptoid mimics have the potential as a new type of bactericide candidates for citrus disease protection. This article is protected by copyright. All rights reserved.
- Published
- 2020
19. Probing the Dynamics of AcrB Through Disulfide Bond Formation
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Ankit Pandeya, Prasangi Rajapaksha, and Yinan Wei
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General Chemical Engineering ,Mutagenesis ,Mutant ,General Chemistry ,Periplasmic space ,medicine.disease_cause ,Article ,Dithiothreitol ,Chemistry ,chemistry.chemical_compound ,chemistry ,medicine ,Biophysics ,Inner membrane ,Efflux ,Ethidium bromide ,QD1-999 ,Escherichia coli - Abstract
The resistant-nodulation-division (RND) superfamily member tripartite AcrA-AcrB-TolC efflux pump is a major contributor to the multidrug resistance in Escherichia coli. AcrB is the inner membrane protein of the efflux complex and is responsible for the recognition and binding of compounds before their transportation out of the cell. Understanding the dynamics of AcrB during functional rotation in the process of drug efflux is the focus of this study. For this purpose, we introduced six inter-subunit disulfide bonds into the periplasmic domain of AcrB using site-directed mutagenesis to study the importance of the relative flexibility at the inter-subunit interface. Western blot analysis revealed the formation of disulfide bond-linked AcrB oligomers, which were reduced into monomers under reducing conditions. The impact of mutation and formation of disulfide bond on efflux were evaluated via comparison of the minimum inhibitory concentration (MIC) of an acrB knockout strain expressing different mutants. The double Cys mutants tested led to equal or higher susceptibility to AcrB substrates compared to their corresponding single mutants. To determine if the reduction of activity in a double mutant is due to restriction on conformational changes by the disulfide bond formation, ethidium bromide accumulation assays were conducted utilizing dithiothreitol (DTT) as the reducing agent. In two cases, the activities of the double Cys mutants were partially restored by DTT reduction, confirming the importance of relative movement in the respective location for function. These findings provide new insights into the dynamics of the AcrAB-TolC efflux pump in E. coli.
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- 2020
20. Periplasmic Targets for the Development of Effective Antimicrobials against Gram-Negative Bacteria
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Olaniyi Alegun, Yinan Wei, Ankit Pandeya, and Isoiza Ojo
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0301 basic medicine ,Gram-negative bacteria ,Bacteria ,biology ,030106 microbiology ,Periplasmic space ,Antimicrobial ,biology.organism_classification ,Article ,Anti-Bacterial Agents ,Microbiology ,03 medical and health sciences ,030104 developmental biology ,Infectious Diseases ,Antibiotic resistance ,Interaction with host ,Drug Resistance, Multiple, Bacterial ,Gram-Negative Bacteria ,Periplasm ,Efflux ,Cell envelope ,Bacterial outer membrane - Abstract
Antibiotic resistance has emerged as a serious threat to global public health in recent years. Lack of novel antimicrobials, especially new classes of compounds, further aggravates the situation. For Gram-negative bacteria, their double layered cell envelope and an array of efflux pumps act as formidable barriers for antimicrobials to penetrate. While cytoplasmic targets are hard to reach, proteins in the periplasm are clearly more accessible, as the drug only needs to breach the outer membrane. In this review, we summarized recent efforts on the validation and testing of periplasmic proteins as potential antimicrobial targets and the development of related inhibitors that either inhibit the growth of a bacterial pathogen or reduce its virulence during interaction with host cells. We conclude that the periplasm contains a promising pool of novel antimicrobial targets that should be scrutinized more closely for the development of effective treatment against multidrug-resistant Gram-negative bacteria.
- Published
- 2020
21. Designing a Renewal Approach of Rejuvenating Historic Districts: Taking Nantong Temple Street as an Example
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Haiyan Gu, Yinan Wei, and Haichun Zhao
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Article Subject ,Computer Networks and Communications ,Computer Science Applications - Abstract
In recent years, people’s opinions have shifted with the continuous development and growth of cities. The category of historical heritage is increasingly being shifted from the city’s star fire to the backdrop color of the entire city. However, some cities are experiencing issues such as aging, regeneration, and stagnation. With the merging of sustainable development ideas with urban renewal techniques, sustainable urban renewal has developed as a new area of research. Data mining and analytics have played a significant role in extracting knowledge and decision-making in the revitalization of historic districts during the last decade. Machine learning, as a computational engine for learning analytics, is a fundamental technique for extracting information, data pattern detection, and prediction. From the perspective of machine learning, this study investigates the historical block update approach, which is utilized in feature space and culture at the same time. Furthermore, it investigates the development of countermeasures for injecting new energy into the historical block by using the functions of space and scale to search for the block transformation and the combination of natural and cultural landscapes. In addition, in order to interact with visitors and residents and realize the renewal of old blocks, in this research work, multifunctional culture is grafted into the historical block and buried underground, so that their life can be awakened. To highlight the efficiency of this work, we have taken the Nantong Temple Street in China as an example which verifies the validity of this study.
- Published
- 2022
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22. Pyroptosis-Induced Inflammation and Tissue Damage
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Ling Yang, Ankit Pandeya, Zhenyu Li, Yinan Wei, Yan Zhang, and Jian Cui
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Inflammation ,Programmed cell death ,business.industry ,Inflammasomes ,Inflammatory response ,Cell ,Pyroptosis ,Inflammasome ,Apoptosis ,Article ,Cell biology ,Signaling system ,medicine.anatomical_structure ,Structural Biology ,Tissue damage ,Medicine ,Cytokines ,Humans ,medicine.symptom ,business ,Molecular Biology ,medicine.drug - Abstract
Programmed cell deaths are pathways involving cells playing an active role in their own destruction. Depending on the signaling system of the process, programmed cell death can be divided into two categories, pro-inflammatory and non-inflammatory. Pyroptosis is a pro-inflammatory form of programmed cell death. Upon cell death, a plethora of cytokines are released and trigger a cascade of responses from the neighboring cells. The pyroptosis process is a double-edged sword, could be both beneficial and detrimental in various inflammatory disorders and disease conditions. A physiological outcome of these responses is tissue damage, and sometimes death of the host. In this review, we focus on the inflammatory response triggered by pyroptosis, and resulting tissue damage in selected organs.
- Published
- 2021
23. Transport Across Two Membrane Bilayers in E. coli by Efflux Pumps of Different Dimensions
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Lan Li, Ankit Pandeya, Isoiza Ojo, Ling Yang, Yinan Wei, and Zhenyu Li
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Lipoproteins ,Mutant ,Microbial Sensitivity Tests ,Peptidoglycan ,Protein complex assembly ,chemistry.chemical_compound ,Structural Biology ,Escherichia coli ,Inner membrane ,Molecular Biology ,Escherichia coli Proteins ,Nile red ,Membrane Transport Proteins ,Biological Transport ,Periplasmic space ,biochemical phenomena, metabolism, and nutrition ,Anti-Bacterial Agents ,chemistry ,Biophysics ,Efflux ,Cell envelope ,Multidrug Resistance-Associated Proteins ,Protein Multimerization ,Bacterial outer membrane ,Carrier Proteins ,Bacterial Outer Membrane Proteins - Abstract
AcrAB-TolC and CusBAC are two of the most well-studied Resistance-Nodulation-Division (RND) family tripartite efflux pumps in E. coli. AcrAB-TolC is a multidrug efflux system, while CusBAC transports Cu(I), Cu(II) and Ag(I). The RND pump complexes span both the inner membrane (IM) and the outer membrane (OM). The long axis dimension of the fully assembled AcrAB-TolC is ∼3 nm longer than that of CusBAC. To probe if these two efflux systems with different dimensions affect each other when they need to work simultaneously in the same cell, two real-time assays were used to monitor the efflux activities of these two pumps and their impact on each other. The results showed that the presence of AcrAB-TolC substrates accelerated the accumulation of Cu(I) in BW25113 but not in BW25113ΔcusBA or BW25113ΔtolC strains. Similarly, the presence of Ag(I) slowed down the Nile red efflux in the parent strain more significantly than in the CusBA deficient mutant. To further investigate the impact of the OM/IM distance on the function of these tripartite complexes, we experimented with strains lacking the lipoprotein Lpp or containing Lpp mutant of different lengths. Data from efflux/accumulation assays and susceptibility tests revealed that mutation of Lpp resulted in functional deficiency of both AcrAB-TolC and CusBAC. In conclusion, this study demonstrated that when AcrAB-TolC and CusBAC functioned simultaneously, it took the cell a few minutes to adjust. Furthermore, the presence of Lpp of proper length is important to support full efflux activity of transporters spanning both membrane layers in E. coli.
- Published
- 2021
24. Inflammasome activation promotes venous thrombosis through pyroptosis
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Toshihiko Shiroishi, Congqing Wu, Min Tao, Nigel Mackman, Ahmed Abdel-Latif, Guoying Zhang, Susan S. Smyth, Yinan Wei, Yan Zhang, Jian Cui, and Zhenyu Li
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Inflammasomes ,Deep vein ,030204 cardiovascular system & hematology ,Inferior vena cava ,Fibrin ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Pyroptosis ,Medicine ,Animals ,Venous Thrombosis ,biology ,business.industry ,Intracellular Signaling Peptides and Proteins ,Inflammasome ,Hematology ,Phosphate-Binding Proteins ,medicine.disease ,Thrombosis ,Stimulus Report ,Mice, Inbred C57BL ,Venous thrombosis ,030104 developmental biology ,medicine.anatomical_structure ,medicine.vein ,Coagulation ,biology.protein ,business ,medicine.drug - Abstract
Crosstalk between coagulation and innate immunity contributes to the progression of many diseases, including infection and cardiovascular disease. Venous thromboembolism (VTE), including pulmonary embolism and deep vein thrombosis (DVT), is among the most common causes of cardiovascular death. Here, we show that inflammasome activation and subsequent pyroptosis play an important role in the development of venous thrombosis. Using a flow restriction–induced mouse venous thrombosis model in the inferior vena cava (IVC), we show that deficiency of caspase-1, but not caspase-11, protected against flow restriction–induced thrombosis. Interleukin-1β expression increased in the IVC following ligation, indicating that inflammasome is activated during injury. Deficiency of gasdermin D (GSDMD), an essential mediator of pyroptosis, protected against restriction-induced venous thrombosis. After induction of venous thrombosis, fibrin was deposited in the veins of wild-type mice, as detected using immunoblotting with a monoclonal antibody that specifically recognizes mouse fibrin, but not in the caspase-1–deficient or GSDMD-deficient mice. Depletion of macrophages by gadolinium chloride or deficiency of tissue factor also protected against venous thrombosis. Our data reveal that tissue factor released from pyroptotic monocytes and macrophages following inflammasome activation triggers thrombosis.
- Published
- 2021
25. Biotinylation as a Tool to Enhance Uptake of Compounds in Gram‐negative Bacteria
- Author
-
Ling Yang, Ankit Pandeya, Yinan Wei, and Olaniyi Alegun
- Subjects
Gram-negative bacteria ,biology ,Chemistry ,Biotinylation ,Genetics ,biology.organism_classification ,Molecular Biology ,Biochemistry ,Biotechnology ,Microbiology - Published
- 2021
26. Automatic segmentation of arterial tree from 3D computed tomographic pulmonary angiography (CTPA) scans
- Author
-
Yinan Wei, Haoyuan Zhang, Chi Zhang, Tongxi Liu, Mingxia Sun, and Sheng Xie
- Subjects
medicine.medical_specialty ,Fuzzy connectedness ,pulmonary embolism ,Computed Tomography Angiography ,lcsh:Surgery ,Contrast Media ,Datasets as Topic ,Pulmonary Artery ,lcsh:Computer applications to medicine. Medical informatics ,3D vessel enhancement ,Computed tomographic ,Pattern Recognition, Automated ,Machine Learning ,Imaging, Three-Dimensional ,Pulmonary angiography ,Medicine ,Humans ,skin and connective tissue diseases ,business.industry ,lcsh:RD1-811 ,medicine.disease ,Arterial tree ,fuzzy connectedness ,Computer Science Applications ,Pulmonary embolism ,Fully automatic ,Automatic segmentation ,Radiographic Image Interpretation, Computer-Assisted ,Pulmonary artery segmentation ,lcsh:R858-859.7 ,Surgery ,sense organs ,Radiology ,Family Practice ,business ,Algorithms - Abstract
Pulmonary embolism (PE) and other pulmonary vascular diseases, have been found associated with the changes in arterial morphology. To detect arterial changes, we propose a novel, fully automatic method that can extract pulmonary arterial tree in computed tomographic pulmonary angiography (CTPA) images. The approach is based on the fuzzy connectedness framework, combined with 3D vessel enhancement and Harris Corner detection to achieve accurate segmentation. The effectiveness and robustness of the method is validated in clinical datasets consisting of 10 CT angiography scans (6 without PE and 4 with PE). The performance of our method is compared with manual classification and machine learning method based on random forest. Our method achieves a mean accuracy of 92% when compared to manual reference, which is higher than the 89% accuracy achieved by machine learning. This performance of the segmentation for pulmonary arteries may provide a basis for the CAD application of PE.
- Published
- 2019
27. Gasdermin D (GSDMD) as a new target for the treatment of infection
- Author
-
Yinan Wei, Zhenyu Li, Ankit Pandeya, and Lan Li
- Subjects
Pharmacology ,010405 organic chemistry ,Effector ,Mechanism (biology) ,Organic Chemistry ,Pyroptosis ,Druggability ,Pharmaceutical Science ,Gasdermin D ,Inflammasome ,Computational biology ,Biology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Mini review ,Chemistry ,010404 medicinal & biomolecular chemistry ,Drug Discovery ,medicine ,Molecular Medicine ,Function (biology) ,medicine.drug - Abstract
The discovery of a previously unknown protein, gasdermin D (GSDMD), as the key effector that leads to pyroptosis and NETosis has created much excitement. Since its initial report in Oct. 2015, more than 200 papers have been published on studies of the structure and mechanism of GSDMD and its homologues. The clear connection between infection and inflammasome activation made GSDMD a promising target for the development of anti-infection treatment. In this mini review, we discuss first the current understanding of the structure and mechanism of GSDMD, focusing on its potential as a druggable target, and then recent efforts in the development of inhibitors to interfere with the pore-forming function of GSDMD and thus alleviate the detrimental effects due to pyroptotic cell death.
- Published
- 2019
28. Extracellular Histones Trigger Disseminated Intravascular Coagulation by Lytic Cell Death
- Author
-
Susan S. Smyth, Lan Li, Jian Cui, Daniel Kirchhofer, Jeremy P. Wood, Ankit Pandeya, Yan Zhang, Zhenyu Li, Congqing Wu, Guoying Zhang, and Yinan Wei
- Subjects
Programmed cell death ,Inflammasomes ,Caspase 1 ,Catalysis ,Thromboplastin ,Histones ,Inorganic Chemistry ,Tissue factor ,Mice ,medicine ,Pyroptosis ,Animals ,Physical and Theoretical Chemistry ,Molecular Biology ,Spectroscopy ,Disseminated intravascular coagulation ,Chemistry ,Organic Chemistry ,Inflammasome ,General Medicine ,Disseminated Intravascular Coagulation ,medicine.disease ,Cell biology ,Computer Science Applications ,Coagulation ,Lytic cycle ,medicine.drug - Abstract
Histones are cationic nuclear proteins that are essential for the structure and functions of eukaryotic chromatin. However, extracellular histones trigger inflammatory responses and contribute to death in sepsis by unknown mechanisms. We recently reported that inflammasome activation and pyroptosis trigger coagulation activation through a tissue factor (TF)-dependent mechanism. Here, we show that histones trigger coagulation activation in vivo as evidenced by coagulation parameters and fibrin deposition in tissues. However, histone-induced coagulopathy was neither dependent on caspase 1/11 and gasdermin D (GSDMD), nor on TLR2 and TLR4, as deficiency of these genes in mice did not protect against histone-induced coagulopathy. Incubation of histones with macrophages induced lytic cell death and phosphatidylserine (PS) exposure, which is required for TF activity, a key initiator of coagulation. Neutralization of TF diminished histone-induced coagulation. Our findings reveal lytic cell death as a novel mechanism of histone-induce coagulation activation and thrombosis.Key PointsHistones trigger DIC in a tissue factor dependent mechanismHistones induce tissue factor activation through lytic cell death
- Published
- 2022
29. Comparison of in vitro and in vivo oligomeric states of a wild type and mutant trimeric inner membrane multidrug transporter
- Author
-
Thomas Wilkop, Prasangi Rajapaksha, Yuguang Cai, Yinan Wei, Wei Lu, and Zhaoshuai Wang
- Subjects
0301 basic medicine ,AcrB diffusion coefficient ,Biophysics ,Trimer ,7. Clean energy ,Biochemistry ,lcsh:Biochemistry ,Cell membrane ,03 medical and health sciences ,medicine ,Inner membrane ,lcsh:QD415-436 ,lcsh:QH301-705.5 ,Membrane protein oligomer ,Chemistry ,Wild type ,Fluorescence recovery after photobleaching ,3. Good health ,030104 developmental biology ,Membrane ,Förster resonance energy transfer ,medicine.anatomical_structure ,lcsh:Biology (General) ,Membrane protein ,FRET ,FRAP ,Disulfide trapping ,Research Article - Abstract
Many membrane proteins exist and function as oligomers or protein complexes. Routine analytical methods involve extraction and solubilization of the proteins with detergents, which could disturb their actual oligomeric state. AcrB is a trimeric inner membrane multidrug transporter in E. coli. In previous studies, we created a mutant AcrBP223G, which behaves like a monomer when extracted from the cell membrane. However, the actual oligomeric state of AcrBP223G in cell membranes remained unclear, which complicated the interpretation of the mechanism by which the mutation affects function. Here we used several complementary methods to determine the oligomeric state of AcrBP223G in E. coli cell membranes. Two sets of quantitative fluorescent techniques were exploited. For these, we created fluorescent tagged AcrB, AcrB-CFP and AcrB-YPet. Fluorescence resonance energy transfer (FRET) and fluorescence recovery after photobleaching (FRAP) were employed to characterize independently the efficiency of energy transfer between co-expressed AcrB-CFP and AcrB-YPet, and the diffusion coefficient of AcrB-YPet and AcrBP223G-YPet in live E. coli cells. Second, we introduced Cys pairs at the inter-subunit interface and used controlled oxidation to probe inter-subunit distances. The results from all studies converge on the conclusion that AcrBP223G exists as a trimer in cell membranes, which dissociates during the purification steps. The small change in trimer affinity and structure leads to a significant loss of AcrB activity. In addition, throughout this study we developed protocols and established benchmark values, useful for further studies on membrane protein associations in cell membranes., Graphical abstract fx1, Highlights • AcrB function is highly sensitive to trimer stability. • Diffusion coefficient was determined for AcrB trimer in live E. coli cells. • Energy transfer was quantified in CFP and YPet tagged AcrB trimer. • Detergent extraction may lead to wrong conclusion about membrane protein complex.
- Published
- 2018
30. Emergence of Two AcrB Substitutions Conferring Multidrug Resistance to Salmonella spp
- Author
-
Xiao-Ling Lin, Yinan Wei, Li-Juan Zhang, Zhenling Zeng, Hong-Xia Jiang, Ling Yang, and Haiyang Shi
- Subjects
Pharmacology ,chemistry.chemical_classification ,0303 health sciences ,030306 microbiology ,Chemistry ,Mutant ,Mutagenesis ,Drug resistance ,Amino acid ,Multiple drug resistance ,03 medical and health sciences ,Infectious Diseases ,Plasmid ,Antibiotic resistance ,Biochemistry ,Pharmacology (medical) ,Efflux ,030304 developmental biology - Abstract
AcrAB-TolC is a major tripartite multidrug efflux pump conferring resistance to a wide variety of compounds in Gram-negative pathogens. Many AcrB mutants have been constructed through site-directed mutagenesis to probe the mechanism of AcrB function in antibiotic resistance. However, much less is known about the actual drug resistance related mutants that naturally occur in clinically isolated pathogens. Here, we report two novel AcrB substitutions, M78I and P319L, in clinically isolated Salmonella strains with high-level ciprofloxacin resistance. Plasmids expressing the detected acrB mutations were constructed and introduced into SL1344△acrB Antimicrobial susceptibility assay showed that all AcrB M78I, AcrB P319L and AcrB M78I/319L conferred reduced susceptibilities to multiple substrates, including fluoroquinolones, erythromycin, tetracyclines, bile salts and dyes. Site-directed mutagenesis and MIC results revealed that increased hydrophobicity of M78I was one of the reasons why AcrB M78I had lower susceptibility to fluoroquinolones. Fluorescence labeling experiments suggested that the AcrB M78I substitution enhanced the binding of substrates to certain amino acid sites in the efflux pathway (e.g., site Q89, E673 and F617) and weakened the binding to other amino acids (e.g., S134 and N274). Structural modeling disclosed the increased flexibility of Leu was favorable for the functional rotation of AcrB compared to the original Pro. AcrA 319L makes the functional rotation of AcrB more flexible, this enables substrate efflux more efficiently. In order to understand the mechanism of AcrAB-TolC drug efflux well, interaction between AcrA and AcrB in the role of substrate efflux of AcrAB-TolC should be further investigated.
- Published
- 2021
31. Emergence of two AcrB substitutions conferring multidrug resistance to
- Author
-
Ling, Yang, Haiyang, Shi, Lijuan, Zhang, Xiaoling, Lin, Yinan, Wei, Hongxia, Jiang, and Zhenling, Zeng
- Subjects
Mechanisms of Resistance - Abstract
AcrAB-TolC is a major tripartite multidrug efflux pump conferring resistance to a wide variety of compounds in Gram-negative pathogens. Many AcrB mutants have been constructed through site-directed mutagenesis to probe the mechanism of AcrB function in antibiotic resistance. However, much less is known about the actual drug resistance-related mutants that naturally occur in clinically isolated pathogens. Here, we report two novel AcrB substitutions, M78I and P319L, in clinically isolated Salmonella strains with high-level ciprofloxacin resistance. Plasmids expressing the detected acrB mutations were constructed and introduced into SL1344 ΔacrB. Antimicrobial susceptibility assays showed that AcrB M78I, AcrB P319L, and AcrB M78I/319L all conferred reduced susceptibilities to multiple substrates, including fluoroquinolones, erythromycin, tetracyclines, bile salts, and dyes. Site-directed mutagenesis and MIC results revealed that the increased hydrophobicity of M78I was one of the reasons the AcrB M78I mutant had lower susceptibility to fluoroquinolones. Fluorescence labeling experiments suggested that the AcrB M78I substitution enhanced the binding of substrates to certain amino acid sites in the efflux pathway (e.g., sites Q89, E673, and F617) and weakened the binding to other amino acids (e.g., S134 and N274). Structural modeling disclosed that the increased flexibility of Leu was favorable for the functional rotation of AcrB compared to the original Pro residue. AcrA 319L makes the functional rotation of AcrB more flexible; this enables substrate efflux more efficiently. In order to understand the mechanism of AcrAB-TolC drug efflux well, the interaction between AcrA and AcrB in the role of the substrate efflux of AcrAB-TolC should be further investigated.
- Published
- 2021
32. Biotinylation as a tool to enhance the uptake of small molecules in Gram-negative bacteria
- Author
-
Ling Yang, Chad Risko, Yinan Wei, Olaniyi Alegun, Zhenyu Li, Chamikara Karunasena, and Ankit Pandeya
- Subjects
B Vitamins ,Cytoplasm ,Cell Membranes ,Biochemistry ,chemistry.chemical_compound ,Mathematical and Statistical Techniques ,Biotin ,Antibiotics ,Medicine and Health Sciences ,Post-Translational Modification ,Multidisciplinary ,Organic Compounds ,Antimicrobials ,Statistics ,Drugs ,Vitamins ,Chemistry ,Biotinylation ,Physical Sciences ,Periplasm ,Porin ,Medicine ,Efflux ,Cellular Structures and Organelles ,Cell envelope ,Bacterial outer membrane ,Research Article ,Streptavidin ,Science ,Research and Analysis Methods ,Microbiology ,Microbial Control ,Escherichia coli ,Statistical Methods ,Gram Negative Bacteria ,Pharmacology ,Analysis of Variance ,Organic Chemistry ,Chemical Compounds ,Biology and Life Sciences ,Proteins ,Membrane Proteins ,Bacteriology ,Cell Biology ,Periplasmic space ,Outer Membrane Proteins ,chemistry ,Biophysics ,Mathematics - Abstract
Antibiotic resistance is a major public health concern. The shrinking selection of effective antibiotics and lack of new development is making the situation worse. Gram-negative bacteria more specifically pose serious threat because of their double layered cell envelope and effective efflux systems, which is a challenge for drugs to penetrate. One promising approach to breach this barrier is the “Trojan horse strategy”. In this technique, an antibiotic molecule is conjugated with a nutrient molecule that helps the antibiotic to enter the cell through dedicated transporters for the nutrient. Here, we explored the approach using biotin conjugation with a florescent molecule Atto565 to determine if biotinylation enhances accumulation. Biotin is an essential vitamin for bacteria and is obtained through either synthesis or uptake from the environment. We found that biotinylation enhanced accumulation of Atto565 in E. coli. However, the enhancement did not seem to be due to uptake through biotin transporters since the presence of free biotin had no observable impact on accumulation. Accumulated compound was mostly in the periplasm, as determined by cell fractionation studies. This was further confirmed through the observation that expression of streptavidin in the periplasm specifically enhanced the accumulation of biotinylated Atto565. This enhancement was not observed when streptavidin was expressed in the cytoplasm indicating no significant distribution of the compound inside the cytoplasm. Using gene knockout strains, plasmid complementation and mutagenesis studies we demonstrated that biotinylation made the compound a better passenger through OmpC, an outer membrane porin. Density functional theory (DFT)-based evaluation of the three-dimensional geometries showed that biotinylation did not directly stabilize the conformation of the compound to make it favorable for the entry through a pore. Further studies including molecular dynamics simulations are necessary to determine the possible mechanisms of enhanced accumulation of the biotinylated Atto565.
- Published
- 2021
33. The Influence of Rain Clutter on Analysis of Target Polarization Properties
- Author
-
Yinan Wei, Fang Liu, Dewang Kong, and Ming Lyn
- Subjects
Physics ,Scattering ,Linear polarization ,Polarimetry ,Polarization (waves) ,Computational physics ,law.invention ,symbols.namesake ,law ,symbols ,Radar ,Rayleigh scattering ,Rain and snow mixed ,Physics::Atmospheric and Oceanic Physics ,Circular polarization - Abstract
As we all know, the polarimetric signature of a simple target can be obtained from its scattering matrix, which shows the complete information of target. When the electromagnetic wave travel through in rain medium, the propagation effect should not be ignored. The radar used can work on both circularly polarization and linear polarization mode. For the meteorological targets like rain medium, the reflection symmetry is considered here, basing on that, the analysis of propagation effect matrix at linear and orthogonal characteristic polarization can be easier than circular polarization, because it is the direct consequence of reflection symmetry. Firstly, this paper derives the polarization scattering matrix model of the target when the rain and snow cluster exitand furthermore, derives the scattering matrix inversion equations under two orthogonal vector basis, i.e., linear and orthogonal characteristic polarization. Then, a polarimetric calibration method by analyzing their corresponding polarization information is proposed. Finally, we show the extensive simulation results of sphere and Rayleigh scattering target. The results include the full-polarization scattering matrix inversed and the errors between the measured value and setting value in four polarimetric channels, which all demonstrate the validity of the method in this paper and achieve more accurate polarization characteristics of the target after getting rid of the impacts of rain and snow cluster.
- Published
- 2019
34. Role of Protein Charge Density on Hepatitis B Virus Capsid Formation
- Author
-
Jie Zheng, Tianbo Liu, Zhaoshuai Wang, Panchao Yin, Xinyu Sun, Baiping Ren, Rundong Hu, Qiao Liu, Dong Li, Yinan Wei, Hui Li, and Yunyi Gao
- Subjects
0301 basic medicine ,Viral capsid assembly ,viruses ,General Chemical Engineering ,Dimer ,Mutant ,010402 general chemistry ,01 natural sciences ,Article ,Hepatitis ,lcsh:Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Mutant protein ,2.2 Factors relating to the physical environment ,Aetiology ,Chemistry ,Liver Disease ,Charge density ,Materials Engineering ,General Chemistry ,Chemical Engineering ,Electrostatics ,0104 chemical sciences ,Infectious Diseases ,030104 developmental biology ,lcsh:QD1-999 ,Capsid ,Ionic strength ,Biophysics ,Digestive Diseases - Abstract
The role of electrostatic interactions in the viral capsid assembly process was studied by comparing the assembly process of a truncated hepatitis B virus capsid protein Cp149 with its mutant protein D2N/D4N, which has the same conformational structure but four fewer charges per dimer. The capsid protein self-assembly was investigated under a wide range of protein surface charge densities by changing the protein concentration, buffer pH, and solution ionic strength. Lowering the protein charge density favored the capsid formation. However, lowering charge beyond a certain point resulted in capsid aggregation and precipitation. Interestingly, both the wild-type and D2N/D4N mutant displayed identical assembly profiles when their charge densities matched each other. These results indicated that the charge density was optimized by nature to ensure an efficient and effective capsid proliferation under the physiological pH and ionic strength.
- Published
- 2018
35. Characterization of an acetohydroxy acid synthase mutant conferring tolerance to imidazolinone herbicides in rice (Oryza sativa)
- Author
-
Xinqi Wang, Zhongze Piao, Wan Changzhao, Fang Jun, Yinan Wei, Wei Wang, Shujun Wu, Francesco Zonta, and Bai Jianjiang
- Subjects
0301 basic medicine ,China ,Mutant ,Dwarfism ,Plant Science ,Biology ,medicine.disease_cause ,Polymorphism, Single Nucleotide ,03 medical and health sciences ,Genetics ,medicine ,Imidazolines ,Gene ,health care economics and organizations ,Mutation ,Oryza sativa ,Herbicides ,food and beverages ,Oryza ,medicine.disease ,Crop Production ,Dwarfing ,Acetolactate Synthase ,Horticulture ,030104 developmental biology ,Agronomy ,Paddy field ,Herbicide Resistance ,Weedy rice - Abstract
The acetohydroxy acid synthase S627N mutation confers herbicide tolerance in rice, and the rice variety containing this mutation produces good yields. This variety is commercially viable at Shanghai and Jiangsu regions in China. Weedy rice is a type of rice that produces lower yields and poorer quality grains than cultivated rice. It plagues commercial rice fields in many countries. One strategy to control its proliferation is to develop rice varieties that are tolerant to specific herbicides. Acetohydroxy acid synthase (AHAS) mutations have been found to confer herbicide tolerance to rice. Here, we identified a single mutation (S627N) in AHAS from an indica rice variety that conferred tolerance against imidazolinone herbicides, including imazethapyr and imazamox. A japonica rice variety (JD164) was developed to obtain herbicide tolerance by introducing the mutated indica ahas gene. Imidazolinone application was sufficient to efficiently control weedy rice in the JD164 field. Although the imazethapyr treatment caused dwarfing in the JD164 plants, it did not significantly reduce yields. To determine whether the decrease of the ahas mRNA expression caused the dwarfism of JD164 after imazethapyr application, we detected the ahas mRNA level in plants. The abundance of the ahas mRNA in JD164 increased after imidazolinone application, thus excluding the mRNA expression level as a possible cause of dwarfism. Activity assays showed that the mutated AHAS was tolerant to imidazolinone but the catalytic efficiency of the mutated AHAS decreased in its presence. Moreover, the activity of the mutated AHAS decreased more in the presence of imazethapyr than in the presence of imazamox. We observed no difference in the AHAS secondary structures, but homology modeling suggested that the S627N mutation enabled the substrate to access the active site channel in AHAS, resulting in imidazolinone tolerance. Our work combined herbicides with a rice variety to control weedy rice and showed the mechanism of herbicide tolerance in this rice variety.
- Published
- 2017
36. Environmental monitoring and landscape design of green city based on remote sensing image and improved neural network
- Author
-
Haiyan Gu and Yinan Wei
- Subjects
010504 meteorology & atmospheric sciences ,business.industry ,Ant colony optimization algorithms ,Air pollution ,Soil Science ,Plant Science ,010501 environmental sciences ,Landscape design ,medicine.disease_cause ,01 natural sciences ,Urbanization ,Environmental monitoring ,Spatial ecology ,medicine ,Environmental science ,Environmental impact assessment ,business ,0105 earth and related environmental sciences ,General Environmental Science ,Remote sensing ,Network model - Abstract
In some developed countries in Europe, cities are developing very rapidly, but the rapid development of these countries also has to go through the following stages, which are the three essential development processes of urbanization, counter-urbanization and re-urbanization. My country’s development situation is relatively uneven. In the more developed areas of my country, the speed of urbanization is relatively rapid, such as cities near the Yangtze River Delta and the Pearl River Delta. But with the development of urbanization, these areas are also facing a very troublesome problem, that is, the balance between the development of the city and the environmental ecosystem. In order to monitor this situation, we will use remote sensing technology to conduct a comprehensive survey of the urban environmental ecosystem and analyze the impact and effect of the rapid development of the city on the changes in the ecosystem. This article will focus on the area around the Yangtze River Delta, and investigate the spatial patterns of urban environmental ecosystems by comparing this area with cities in developed regions such as Western Europe and North America. Under the conditions of different regions and different degrees of urbanization, the comprehensive situation of environmental elements in the city is investigated, and the environmental impact effects and the causes, effects and effects of environmental changes are more accurately studied. Combine the BP network model related to the nervous system in the experiment, and continuously optimize the model during the experiment. The experimental data selects environmental difference reports displayed in different years and different seasons to predict the air pollution value of a certain city. The reason why we use this method is that this model can improve the accuracy of statistical data and greatly simplify the unnecessary and complicated steps in the research process, and it can also reduce the error problems generated in the operation of the BP system, such as when we When entering a piece of data, the data obtained is often very different from the target data. Therefore, we will use the ant colony algorithm to solve the above problems, and add stereo and 3D technologies, which can monitor experiments in real time, greatly improve the speed of the experiment, and the 3D stereo technology can make the results more perceptual to meet the needs of the experiment.
- Published
- 2021
37. Insight into the AcrAB-TolC Complex Assembly Process Learned from Competition Studies
- Author
-
Ankit Pandeya, Isoiza Ojo, Thilini Abeywansha, Prasangi Rajapaksha, Ling Yang, and Yinan Wei
- Subjects
assembly ,Microbiology (medical) ,Mutant ,RM1-950 ,medicine.disease_cause ,Biochemistry ,Microbiology ,Article ,dominant negative effect ,Protein–protein interaction ,protein-protein interaction ,Acrab tolc ,03 medical and health sciences ,medicine ,Pharmacology (medical) ,General Pharmacology, Toxicology and Pharmaceutics ,030304 developmental biology ,0303 health sciences ,Mutation ,biology ,030306 microbiology ,Chemistry ,Wild type ,biology.organism_classification ,Cell biology ,Multiple drug resistance ,RND pump ,Infectious Diseases ,Therapeutics. Pharmacology ,Efflux ,mutation ,Bacteria - Abstract
The RND family efflux pump AcrAB-TolC in E. coli and its homologs in other Gram-negative bacteria are major players in conferring multidrug resistance to the cells. While the structure of the pump complex has been elucidated with ever-increasing resolution through crystallography and Cryo-EM efforts, the dynamic assembly process remains poorly understood. Here, we tested the effect of overexpressing functionally defective pump components in wild type E. coli cells to probe the pump assembly process. Incorporation of a defective component is expected to reduce the efflux efficiency of the complex, leading to the so called “dominant negative” effect. Being one of the most intensively studied bacterial multidrug efflux pumps, many AcrA and AcrB mutations have been reported that disrupt efflux through different mechanisms. We examined five groups of AcrB and AcrA mutants, defective in different aspects of assembly and substrate efflux. We found that none of them demonstrated the expected dominant negative effect, even when expressed at concentrations many folds higher than their genomic counterpart. The assembly of the AcrAB-TolC complex appears to have a proof-read mechanism that effectively eliminated the formation of futile pump complex.
- Published
- 2021
38. Donnan Potential across the Outer Membrane of Gram-Negative Bacteria and Its Effect on the Permeability of Antibiotics
- Author
-
Jian Cui, Yinan Wei, Ankit Pandeya, Olaniyi Alegun, and Isoiza Ojo
- Subjects
0301 basic medicine ,Microbiology (medical) ,Gram-negative bacteria ,Membrane permeability ,030106 microbiology ,Donnan potential ,RM1-950 ,Review ,Biochemistry ,Microbiology ,antibiotics ,03 medical and health sciences ,symbols.namesake ,Pharmacology (medical) ,Semipermeable membrane ,General Pharmacology, Toxicology and Pharmaceutics ,Lipid bilayer ,biology ,Chemistry ,Periplasmic space ,biology.organism_classification ,030104 developmental biology ,Infectious Diseases ,Membrane ,membrane permeability ,cellular accumulation ,symbols ,Biophysics ,Therapeutics. Pharmacology ,Bacterial outer membrane - Abstract
The cell envelope structure of Gram-negative bacteria is unique, composed of two lipid bilayer membranes and an aqueous periplasmic space sandwiched in between. The outer membrane constitutes an extra barrier to limit the exchange of molecules between the cells and the exterior environment. Donnan potential is a membrane potential across the outer membrane, resulted from the selective permeability of the membrane, which plays a pivotal role in the permeability of many antibiotics. In this review, we discussed factors that affect the intensity of the Donnan potential, including the osmotic strength and pH of the external media, the osmoregulated periplasmic glucans trapped in the periplasmic space, and the displacement of cell surface charges. The focus of our discussion is the impact of Donnan potential on the cellular permeability of selected antibiotics including fluoroquinolones, tetracyclines, β-lactams, and trimethoprim.
- Published
- 2021
39. Dual-Functional-Tag-Facilitated Protein Labeling and Immobilization
- Author
-
Kevin Kwan, Xinyi Zhang, Wei Lu, Yinan Wei, and Dibakar Bhattacharyya
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,Pyrophosphatase ,010405 organic chemistry ,General Chemical Engineering ,General Chemistry ,Matrix (biology) ,01 natural sciences ,Fluorescence ,Article ,0104 chemical sciences ,Amino acid ,lcsh:Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Enzyme ,chemistry ,Biochemistry ,lcsh:QD1-999 ,Click chemistry ,Enzyme kinetics ,Histidine ,health care economics and organizations - Abstract
An important strategy in the construction of biomimetic membranes and devices is to use natural proteins as the functional components for incorporation in a polymeric or nanocomposite matrix. Toward this goal, an important step is to immobilize proteins with high efficiency and precision without disrupting the protein function. Here, we developed a dual-functional tag containing histidine and the non-natural amino acid azidohomoalanine (AHA). AHA is metabolically incorporated into the protein, taking advantage of the Met-tRNA and Met-tRNA synthetase. Histidine in the tag can facilitate metal-affinity purification, whereas AHA can react with an alkyne-functionalized probe or surface via well-established click chemistry. We tested the performance of the tag using two model proteins, green fluorescence protein and an enzyme pyrophosphatase. We found that the addition of the tag and the incorporation of AHA did not significantly impair the properties of these proteins, and the histidine–AHA tag can facilitate protein purification, immobilization, and labeling.
- Published
- 2017
40. Layer-by-layer assembled membranes with immobilized porins
- Author
-
Xinyi Zhang, Cassandra J. Porter, Sebastián Hernández, Yinan Wei, and Dibakar Bhattacharyya
- Subjects
Chemistry ,General Chemical Engineering ,Vesicle ,Microfiltration ,Layer by layer ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,Polyelectrolyte ,0104 chemical sciences ,Membrane ,Chemical engineering ,Zeta potential ,Nanofiltration ,0210 nano-technology ,Lipid bilayer - Abstract
New and advanced opportunities are arising for the synthesis and functionalization of membranes with selective separation, reactivity, and stimuli-responsive behavior. One such advancement is the integration of bio-based channels in membrane technologies. By a layer-by-layer (LbL) assembly of polyelectrolytes, outer membrane protein F trimers (OmpF) or “porins” from Escherichia coli with central pores ∼2 nm in diameter at their opening and ∼0.7 × 1.1 nm at their constricted region are immobilized within the pores of poly(vinylidene fluoride) microfiltration membranes, in contrast to traditional ruptured lipid bilayer or vesicle processes. These OmpF-membranes demonstrate selective rejection of non-charged organics over ionic solutes, allowing the passage of up to 2 times more salts than traditional nanofiltration membranes starting with rejections of 84% for 0.4 to 1.0 kDa organics. The presence of charged groups in OmpF-membranes also leads to pH-dependent salt rejection through Donnan exclusion. These OmpF-membranes also show exceptional durability and stability, delivering consistent and constant permeability and recovery for over 160 h of operation. Characterization of the solutions containing OmpF and the membranes was conducted during each stage of the process, including detection by fluorescence labelling (FITC), zeta potential, pH responsiveness, flux changes, and rejection of organic–inorganic solutions.
- Published
- 2017
41. Probing the Functional Relevance of the Tip-to-Tip Acrab-Tolc Structural Model
- Author
-
Isoiza Ojo and Yinan Wei
- Subjects
Acrab tolc ,Chemistry ,Biophysics ,Relevance (information retrieval) - Published
- 2020
42. Probing the Dynamic Aspects of AcrB Function through Disulfide Bond Formation
- Author
-
Prasangi Rajapaksha and Yinan Wei
- Subjects
Crystallography ,Chemistry ,Biophysics ,Disulfide bond ,Function (biology) - Published
- 2020
43. Application of Fluorescence in Studying Therapeutic Enzymes
- Author
-
Zhaoshuai, Wang, Caihong, Li, and Yinan, Wei
- Subjects
Spectrometry, Fluorescence ,Staining and Labeling ,Fluorescence Resonance Energy Transfer ,Enzymes - Abstract
Fluorescence spectroscopy is one of the most important techniques in the study of therapeutic enzymes. The fluorescence phenomenon has been discovered and exploited for centuries, while therapeutic enzymes have been used in treatment of disease for only decades. This chapter provides a brief summary of the current applications of fluorescence methods in studying therapeutic enzymes to provide some insights on the selection of proper method tailored to the goal. First a brief introduction about therapeutic enzymes and history of fluorescence were provided, followed by discussions on how fluorescence was applied in the studies. Four popular fluorescence methods are discussed: fluorescence tracing, fluorescence resonance energy transfer (FRET), fluorescence quenching and fluorescence polarization. Selected application of the fluorescence methods in studying therapeutic enzymes are listed, and discussed in details in the following paragraphs.
- Published
- 2019
44. Increasing Salt Rejection of Polybenzimidazole Nanofiltration Membranes via the Addition of Immobilized and Aligned Aquaporins
- Author
-
Ryan Blood, Priyesh Wagh, Prasangi Rajapaksha, Isabel C. Escobar, Yinan Wei, Peter M. Kekenes-Huskey, and Xinyi Zhang
- Subjects
Aquaporin ,Bioengineering ,02 engineering and technology ,lcsh:Chemical technology ,010402 general chemistry ,01 natural sciences ,Article ,lcsh:Chemistry ,Boric acid ,chemistry.chemical_compound ,Chemical Engineering (miscellaneous) ,lcsh:TP1-1185 ,aquaporins ,chemistry.chemical_classification ,Process Chemistry and Technology ,Polymer ,biomimetic ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Membrane ,lcsh:QD1-999 ,chemistry ,Covalent bond ,nanofiltration ,immobilization ,Urea ,Nanofiltration ,0210 nano-technology ,Nuclear chemistry ,Cysteine - Abstract
Aquaporins are water channel proteins in cell membrane, highly specific for water molecules while restricting the passage of contaminants and small molecules, such as urea and boric acid. Cysteine functional groups were installed on aquaporin Z for covalent attachment to the polymer membrane matrix so that the proteins could be immobilized to the membranes and aligned in the direction of the flow. Depth profiling using x-ray photoelectron spectrometer (XPS) analysis showed the presence of functional groups corresponding to aquaporin Z modified with cysteine (Aqp-SH). Aqp-SH modified membranes showed a higher salt rejection as compared to unmodified membranes. For 2 M NaCl and CaCl2 solutions, the rejection obtained from Aqp-SH membranes was 49.3 ±, 7.5% and 59.1 ±, 5.1%. On the other hand, the rejections obtained for 2 M NaCl and CaCl2 solutions from unmodified membranes were 0.8 ±, 0.4% and 1.3 ±, 0.2% respectively. Furthermore, Aqp-SH membranes did not show a significant decrease in salt rejection with increasing feed concentrations, as was observed with other membranes. Through simulation studies, it was determined that there was approximately 24% capping of membrane pores by dispersed aquaporins.
- Published
- 2019
45. Study of Multidrug Efflux System Protein Degradation in E. coli Using Transposons Library
- Author
-
Yinan Wei and Prasangi Rajapaksha
- Subjects
Transposable element ,Biochemistry ,Chemistry ,Genetics ,Efflux ,Protein degradation ,Molecular Biology ,Biotechnology - Published
- 2019
46. Application of Fluorescence in Studying Therapeutic Enzymes
- Author
-
Yinan Wei, Zhaoshuai Wang, and Caihong R. Li
- Subjects
chemistry.chemical_classification ,Enzyme ,Förster resonance energy transfer ,chemistry ,Biochemistry ,Fluorescence ,Fluorescence anisotropy ,Fluorescence spectroscopy ,Therapeutic enzyme - Abstract
Fluorescence spectroscopy is one of the most important techniques in the study of therapeutic enzymes. The fluorescence phenomenon has been discovered and exploited for centuries, while therapeutic enzymes have been used in treatment of disease for only decades. This chapter provides a brief summary of the current applications of fluorescence methods in studying therapeutic enzymes to provide some insights on the selection of proper method tailored to the goal. First a brief introduction about therapeutic enzymes and history of fluorescence were provided, followed by discussions on how fluorescence was applied in the studies. Four popular fluorescence methods are discussed: fluorescence tracing, fluorescence resonance energy transfer (FRET), fluorescence quenching and fluorescence polarization. Selected application of the fluorescence methods in studying therapeutic enzymes are listed, and discussed in details in the following paragraphs.
- Published
- 2019
47. Distribution of fluoroquinolones in the two aqueous compartments of Escherichia coli
- Author
-
Yinan Wei, Ankit Pandeya, Yuguang Cai, and Olaniyi Alegun
- Subjects
0301 basic medicine ,Gram-negative bacteria ,Biophysics ,medicine.disease_cause ,Biochemistry ,Microbiology ,lcsh:Biochemistry ,03 medical and health sciences ,Minimum inhibitory concentration ,0302 clinical medicine ,Fluoroquinolone ,medicine ,lcsh:QD415-436 ,lcsh:QH301-705.5 ,Escherichia coli ,biology ,Chemistry ,Periplasmic space ,biology.organism_classification ,030104 developmental biology ,lcsh:Biology (General) ,Cytoplasm ,Periplasm accumulation ,030220 oncology & carcinogenesis ,Efflux ,Cell envelope ,Bacteria ,Research Article - Abstract
The double-layered cell envelope of Gram-negative bacteria and active drug efflux present a formidable barrier for antimicrobial compounds to penetrate. Fluoroquinolones are among the few classes of antimicrobials that are clinically useful in the treatment of Gram-negative bacterial infection. Previous studies on fluoroquinolone accumulation measured total bacteria associated compounds, rather than the cytoplasmic accumulation. Fluoroquinolones target the type II topoisomerases in the cytoplasm. Thus, the cytoplasmic accumulation is expected to be more relevant to the potency of the drugs. Here, we fractionated and measured the concentration of nine fluoroquinolone compounds in the periplasm and the cytoplasm of two strains of E. coli cells, a parent strain and its isogenic efflux-deficient tolC knockout strain. The potency of the drugs was determined using the minimum inhibitory concentration (MIC) assay. We found that all fluoroquinolones tested accumulated at much higher concentrations in the periplasm than in the cytoplasm. The periplasmic concentrations were 2–15 folds higher than the cytoplasmic concentration, while the actual distribution ratio varies drastically among the compounds tested. Good correlation between the MIC and the cytoplasmic accumulation, but not whole cell accumulation, was observed using a pair of isogenic wild type and drug-efflux deficient strains., Graphical abstract Image 1, Highlights • Fluoroquinolones accumulate to high concentration in the periplasm of E. coli • Periplasmic concentrations are higher than the cytoplasmic and exterior media concentration. • Good correlation was observed for the cytoplasmic drug concentration and the antimicrobial potency. • Disruption of active efflux has a larger impact on the periplasmic than the cytoplasmic accumulation.
- Published
- 2020
48. The ssrA-Tag Facilitated Degradation of an Integral Membrane Protein
- Author
-
Qian Chai, Yinan Wei, Zhaoshuai Wang, Rebecca Ellis Dutch, and Stacy R. Webb
- Subjects
Models, Molecular ,0301 basic medicine ,Proteases ,Protein Conformation ,Proteolysis ,Biology ,Biochemistry ,Article ,03 medical and health sciences ,Protein sequencing ,Protein structure ,Escherichia coli ,medicine ,Humans ,Amino Acid Sequence ,Integral membrane protein ,Peptide sequence ,Escherichia coli Infections ,030102 biochemistry & molecular biology ,medicine.diagnostic_test ,Escherichia coli Proteins ,Endopeptidase Clp ,Cell biology ,030104 developmental biology ,Membrane protein ,Chaperone (protein) ,biology.protein ,Multidrug Resistance-Associated Proteins - Abstract
ATP-dependent degradation plays a critical role in the quality control and recycling of proteins in cells. However, complete degradation of membrane proteins by ATP-dependent proteases in bacteria is not well-studied. We discovered that the degradation of a multidomain and multispan integral membrane protein AcrB could be facilitated by the introduction of a ssrA-tag at the C-terminus of the protein sequence and demonstrated that the cytoplasmic unfoldase-protease complex ClpXP was involved in the degradation. This is the first report to our knowledge to reveal that the ClpXP complex is capable of degrading integral membrane proteins. The chaperone SspB also played a role in the degradation. Using purified proteins, we demonstrated that the addition of the ssrA-tag did not drastically affect the structure of AcrB, and the degradation of detergent solubilized AcrB by purified ClpXP could be observed in vitro.
- Published
- 2016
49. Subcellular Accumulation of Fluoroquinolones in E. coli
- Author
-
Olaniyi Alegun, Yinan Wei, and Ankit Pandeya
- Subjects
Biochemistry ,Chemistry ,Biophysics - Published
- 2020
50. Inflammasome Activation Triggers Blood Clotting and Host Death through Pyroptosis
- Author
-
Xuyan Shi, Yohei Hisada, Susan S. Smyth, Wei Lu, Lan Li, Guoying Zhang, Yinan Wei, Toshihiko Shiroishi, Binggang Xiang, Alan Daugherty, Zhenyu Li, Steven P. Grover, Jumei Shi, Xiang-An Li, Xinyi Zhang, Daniel Kirchhofer, Feng Shao, Yan Zhang, Nigel Mackman, and Congqing Wu
- Subjects
0301 basic medicine ,Lipopolysaccharides ,Programmed cell death ,Lipopolysaccharide ,Inflammasomes ,Immunology ,Inflammation ,Biology ,Monocytes ,Type three secretion system ,Thromboplastin ,03 medical and health sciences ,chemistry.chemical_compound ,Tissue factor ,Mice ,0302 clinical medicine ,Cell-Derived Microparticles ,medicine ,Pyroptosis ,Immunology and Allergy ,Animals ,Humans ,Blood Coagulation ,Macrophages ,Inflammasome ,Thrombosis ,Bacterial Infections ,Cell biology ,Disease Models, Animal ,030104 developmental biology ,Infectious Diseases ,Coagulation ,chemistry ,030220 oncology & carcinogenesis ,Caspases ,medicine.symptom ,Biomarkers ,medicine.drug ,Signal Transduction - Abstract
Inflammasome activation and subsequent pyroptosis are critical defense mechanisms against microbes. However, overactivation of inflammasome leads to death of the host. Although recent studies have uncovered the mechanism of pyroptosis following inflammasome activation, how pyroptotic cell death drives pathogenesis, eventually leading to death of the host, is unknown. Here, we identified inflammasome activation as a trigger for blood clotting through pyroptosis. We have shown that canonical inflammasome activation by the conserved type III secretion system (T3SS) rod proteins from Gram-negative bacteria or noncanonical inflammasome activation by lipopolysaccharide (LPS) induced systemic blood clotting and massive thrombosis in tissues. Following inflammasome activation, pyroptotic macrophages released tissue factor (TF), an essential initiator of coagulation cascades. Genetic or pharmacological inhibition of TF abolishes inflammasome-mediated blood clotting and protects against death. Our data reveal that blood clotting is the major cause of host death following inflammasome activation and demonstrate that inflammasome bridges inflammation with thrombosis.
- Published
- 2018
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