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The production of fermentable sugars from lignocellulosic biomass is achieved by the synergistic action of a group of enzymes called cellulases. Cellulose is a long chain of chemically linked glucoses by β-1,4 bonds. The enzyme β-1,4-endoglucanase is the first cellulase involved in the degradation, breaking the bond of the amorphous regions. A β-1,4-endoglucanase enzyme with high activity was obtained from a Bacillus subtilis strain isolated from wastewater of a pulp and paper mill. Sequencing and bioinformatic analysis showed that the gene amplified by PCR consisting of 1407 nucleotides and coding for a β-1,4-endoglucanase enzyme of approximately 55 kDa. The open reading frame (ORF) encoding the mature endoglucanase (eglS) was successfully inserted in a modified cloning plasmid (pITD03) and into the pYD1 plasmid used for its expression in yeast. Carboxymethylcellulose (CMC) plate assay, SDS-PAGE, and zymogram confirmed the production and secretion by the transformed E. coli BL21-SI strain of a 39 kDa β-1,4-endoglucanase consistent with the catalytic domain without the cellulose-binding module (CBM). The results showed that the truncated β-1,4-endoglucanase had higher activity and stability. • A strain of Bacillus subtilis with endoglucanase activity was isolated from the wastewater of a pulp and paper mill. • The endoglucanase gene was inserted into a modified plasmid (E. coli) and into pYD1 (S. cerevisiae). • The endoglucanase in pYD1 is expressed with good activity in E. coli , being the first report of this finding. • A truncated recombinant endoglucanase is obtained and is very stable at pH (2-10) and temperature (30–55 °C). [ABSTRACT FROM AUTHOR]

Kinetic models are key to understanding and predicting the dynamic behaviour of metabolic systems. Traditional models require kinetic parameters which are not always available and are often estimated in vitro. Ensemble models overcome this challenge by sampling thermodynamically feasible models around a measured reference point. However, it is unclear if the convenient distributions used to generate the ensemble produce a natural distribution of model parameters and hence if the model predictions are reasonable. In this paper, we produced a detailed kinetic model for the central carbon metabolism of Escherichia coli. The model consists of 82 reactions (including 13 reactions with allosteric regulation) and 79 metabolites. To sample the model, we used metabolomic and fluxomic data from a single steady-state time point for E. coli K-12 MG1655 growing on glucose minimal M9 medium (average sampling time for 1000 models: 11.21 ± 0.14 min). Afterwards, in order to examine whether our sampled models are biologically sound, we calculated K m , V max and k cat for the reactions and compared them to previously published values. Finally, we used metabolic control analysis to identify enzymes with high control over the fluxes in the central carbon metabolism. Our analyses demonstrate that our platform samples thermodynamically feasible kinetic models, which are in agreement with previously published experimental results and can be used to investigate metabolic control patterns within cells. This renders it a valuable tool for the study of cellular metabolism and the design of metabolic pathways. • We present a kinetic model for central carbon metabolism in Escherichia coli. • Metabolomics and fluxomics reference data were used for sampling the kinetic model. • GRASP uses prior knowledge of kinetic mechanisms with thermodynamics and omics data. • Kinetic parameters were calculated and compared to literature. • The GRASP metabolic control analysis can be used to identify enzymes of interest. [ABSTRACT FROM AUTHOR]

The synthesized WO 3 /g-C 3 N 4 /BiOI photocatalyst followed a double S-scheme transfer process. The active species in the photocatalytic antibacterial process were h+, e−, OH and O2− under LED light. The double S-scheme structure promotes the separation efficiency of electron-hole pairs and increases the redox capacity of the heterojunction, which further improves the antibacterial performance for E. coli and S. aureus. [Display omitted] • Novel double S-scheme WO 3 /g-C 3 N 4 /BiOI photocatalyst was synthesized. • WO 3 /g-C 3 N 4 /BiOI can remove E. coli in 12 min and S. aureus in 20 min. • The active species are h+, e−, OH and O 2 −. • Double S-scheme promotes the electrons and holes separation. • Double S- scheme increases the redox capacity of the heterojunction. In recent years, the threat to human health from bacteria in wastewater has attracted attention, and photocatalytic technology has emerged as a promising strategy for inactivating bacteria in water. Therefore, it is of great research value to develop a novel high-efficiency photocatalytic system with the visible light response. We successfully designed a double S-scheme heterojunction composite WO 3 /g-C 3 N 4 /BiOI (WCB) in this paper. The preparation of WCB composites was demonstrated by a series of characterizations, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM). The antibacterial effects of photocatalysts against representative Gram-negative strain Escherichia coli (E. coli) and Gram-positive strain Staphylococcus aureus (S. aureus) were tested under LED light irradiation. The novel photocatalyst presented excellent antibacterial properties, inactivating E. coli in 12 min and S. aureus in 20 min. The bacterial cell inactivation process was studied by scanning electron microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Active species capture experiments show that the active species present in the WCB composites in the process of inactivating bacteria are h+, e−, OH and O 2 −. In conclusion, the synthesized double S-scheme WCB photocatalyst exhibits remarkable photocatalytic antibacterial activity under LED light and has broad prospects for practical application in water antibacterial treatment. [ABSTRACT FROM AUTHOR]

A novel Z-scheme heterostructure of Bi 12 O 15 Cl 6 /InVO 4 composite was synthesized by a hydrothermal and calcination process. The composite exhibited excellent degradation and antibacterial properties against TC, RhB, E. coli , and S. aureus under LED light. The synergistic effect of Z-scheme heterostructure played an important role in photocatalytic process. h+, •OH and •O 2 − are all active species in the photocatalytic reaction. The synthesis of Z-scheme Bi 12 O 15 Cl 6 /InVO 4 heterojunction provides a new idea with great potential for application in environmental governance. [Display omitted] The design of a photocatalytic system with Z-scheme heterojunction is the key to charge separation. In this paper, a simple synthesis method was used to prepare Bi 12 O 15 Cl 6 /InVO 4 photocatalyst. The synthesized photocatalyst can effectively degrade pollutants, and inactivate bacteria under LED light irradiation. The optimal ratio of 30% Bi 12 O 15 Cl 6 /InVO 4 material effectively degraded 78.85% of TC and 97.83% of RhB within 90 min and inactivated Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in 40 min. This improvement in photocatalytic performance is mainly due to the formation of a Z-scheme heterojunction between Bi 12 O 15 Cl 6 and InVO 4 , which produces effective charge separation and improves photocatalytic degradation and antibacterial activity. The capture experiment revealed the main active substances. The effects of catalyst dosage and pollutant concentration were investigated in details. The intermediates of TC degradation were identified by mass spectrometry (MS), and the possible photocatalytic degradation pathway was proposed. Capture experiment and related measurements proposed the Z-scheme mechanism. This work emphasizes the importance of heterogeneous structure construction and proposes feasible solutions for the rational design of catalysts with photodegradation and antibacterial properties under LED light. [ABSTRACT FROM AUTHOR]

Pathogenic strains of Escherichia coli infecting poultry, commonly called avian pathogenic E. coli (APEC) present significant risks, to the health of both poultry and the general public. This systematic review aimed to examine the prevalence of APEC serotypes, sequence types (ST), phylogenetic groups, virulence factors and antibiotic resistance patterns based on 189 research papers sourced from PubMed, Web of Science, and ProQuest. Then, data were extracted from the selected studies and analyzed to assess the global distribution and characteristics of APEC strains. The metaprop codes in the Meta and Metafor packages of R as implemented in RStudio were then used to conduct meta-analysis. Among APEC strains identified from these different research reports serogroup O78 had the highest overall prevalence (16 %), followed by serogroups O2 (10 %), and O117 (8 %). The most common ST profiles were ST117 (20 %), ST140 (15 %), ST95 (12 %), and ST131 (9 %). ST117 and ST140 are known reservoirs for pathogenic E. coli in humans. Moreover, phylogenetic assessment highlighted the prevalence of phylogroups A, A1, F, D, and B2 among APEC strains indicating diversity in phylogenetic origin within poultry populations. The presence of antimicrobial resistance was notable among APEC strains against antibiotics such as tetracyclines, penicillins, and cephalosporins. This resistance may be linked to use of antimicrobials in poultry production in certain regions presenting challenges for both animal health management and human infection control. Analysis of sequences linked to adherence or virulence indicated that genes encoding adhesins (csg, fimC), iron/metal uptake (sitB, sitC, iroD) and cytotoxicity (estB, hlyF), and serum resistance (traT, iss) were highly prevalent. These factors have been reported to contribute to APEC host colonization and virulence in poultry. In summary, this overview of the characteristics of APEC highlights the pressing importance of monitoring and implementing management approaches to reduce antimicrobial resistance considering that a phylogenetic diversity of E. coli strains causes infections in both poultry and humans and represents a risk to both animal and public health. Further, determining the major conserved aspects and predominant mechanisms of virulence of APEC is critical for improving diagnostics and developing preventative measures to reduce the burden of infection caused by pathogenic E. coli in poultry and lower risks associated with foodborne transmission of E. coli to humans through poultry and poultry products. • High prevalence of O78, O2 and O117 among APEC strains isolated from clinical cases. • ST117, ST140, and ST95 are the most common ST profiles among APEC strains. • Phylogenetic group A, A1, F, D, and B1 are predominant among APEC strains. • A high level of antimicrobial resistance is observed among APEC strains. • Csg, fimC, sitB, sitC, iroD, estB, and hlyF genes are prevalent among APEC strains. [ABSTRACT FROM AUTHOR]

Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [Display omitted] • Two new compounds [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 were synthesized under room temperature. • Compounds 1 – 2 were both extended into a 3D supermolecule network structure via π ··· π stacking and hydrogen bonding interactions. • Compounds 1 – 2 were both potential antibacterial bacterial for E. coli and MRSA (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). • Molecular docking of protein and DNA for compounds 1 – 2 were investigated. • The potential antibacterial mechanism of compounds 1 – 2 was proposed via combining with theoretical calculation and experimental results. Two new compounds namely [Zn(L1)phen] 3 1 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1 – 2 can form 3D supramolecular network structures through π ··· π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H...H and Cl...H interactions were the predominant interactions in compounds 1 – 2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1 – 2. The inhibitory effects of compounds 1 – 2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1 : E. coli: 18 mm, MRSA: 17 mm, 2 : E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1 – 2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1 – 2 with UDP- N -acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1 – 2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1 – 2 were proposed. [ABSTRACT FROM AUTHOR]

The indiscriminate use of antimicrobials has led to the emergence of resistant bacteria, especially pathogenic strains of Escherichia coli , which are associated with diseases in animals and humans. The aim of the present study was to characterize E. coli isolates in calves with regards to the presence of virulence genes and investigate the resistance of the isolates to different antimicrobials. Between 2021 and 2023, 456 fecal samples were collected from calves in the Pantanal and Cerrado biomes of the state of Mato Grosso do Sul, Brazil. All samples were subjected to microbiological analysis and disc diffusion antibiogram testing. The polymerase chain reaction method was used to detect virulence genes. Bacterial growth was found in 451 of the 456 samples and biochemically identified as Escherichia coli. All 451 isolates (100 %) exhibited some phenotypic resistance to antimicrobials and 67.62 % exhibited multidrug resistance. The frequency of multidrug-resistant isolates in the Cerrado biome was significantly higher than that in the Pantanal biome (p = 0.0001). In the Cerrado , the most common pathotype was Shiga toxin-producing Escherichia coli (STEC) (28 %), followed by toxigenic Escherichia coli (ETEC) (11 %), enterohemorrhagic Escherichia coli (EHEC) (8 %) and enteropathogenic Escherichia coli (EPEC) (2 %). In most cases, the concomitant occurrence of pathotypes was more common, the most frequent of which were ETEC + STEC (33 %), ETEC + EHEC (15 %) and ETEC + EPEC (3 %). The STEC pathotype (30 %) was also found more frequently in the Pantanal , followed by EHEC (12 %), ETEC (9 %) and EPEC (6 %). The STEC pathotype had a significantly higher frequency of multidrug resistance (p = 0.0486) compared to the other pathotypes identified. The frequency of resistance was lower in strains from the Pantanal biome compared to those from the Cerrado biome. Although some factors are discussed in this paper, it is necessary to clarify the reasons for this difference and the possible impacts of these findings on both animal and human health in the region. • Multi-resistant bacteria in cattle in the Cerrado and Pantanal biomes of Brazil. • Antimicrobial multiresistance of E. coli pathotypes isolated from calf feces. • Domestic animals and humans, exchange of pathogens between different species. [ABSTRACT FROM AUTHOR]

Leafy greens, especially lettuce, are repeatedly linked to foodborne outbreaks. This paper studied the susceptibility of different leafy greens to human pathogens. Five commonly consumed leafy greens, including romaine lettuce, green-leaf lettuce, baby spinach, kale, and collard, were selected by their outbreak frequencies. The behavior of E. coli O157:H7 87-23 on intact leaf surfaces and in their lysates was investigated. Bacterial attachment was positively correlated with leaf surface roughness and affected by the epicuticular wax composition. At room temperature, E. coli O157:H7 had the best growth potentials on romaine and green-leaf lettuce surfaces. The bacterial growth was positively correlated with stomata size and affected by epicuticular wax compositions. At 37 °C, E. coli O157:H7 87-23 was largely inhibited by spinach and collard lysates, and it became undetectable in kale lysate after 24 h of incubation. Kale and collard lysates also delayed or partially inhibited the bacterial growth in TSB and lettuce lysate at 37 °C, and they sharply reduced the E. coli O157:H7 population on green leaf lettuce at 4 °C. In summary, the susceptibility of leafy greens to E. coli O157:H7 is determined by a produce-specific combination of physiochemical properties and temperature. • Lysate will not affect E. coli O157:H7 growth and survival on intact leaves. • E. coli 's survival on leaves depends on produce-specific traits and temperature. • Spinach, collard, kale lysates are natural antimicrobials against E. coli O157:H7. • At 37 °C, kale lysate inactivated E. coli O157:H7 in pure culture within 24h. • Kale and collard lysates reduced E. coli population on the lettuce surface at 4 °C. [ABSTRACT FROM AUTHOR]

Nanomaterials containing tungsten (TNMs), characterized by diverse nanostructures had been extensively used in biomedical sector. Despite numerous reports focusing on TNM applications in specific biomedical areas, there is a noticeable absence of comprehensive studies that focused on detailed characterization of nanomaterials along with their biological applications. The present work described the structural, morphological, and antimicrobial properties of tungsten oxide (WO 3) nanoparticles coated by antibiotics (nanobiotics), and their application on single and mixed bacterial culture. The nanobiotics included in this study were WO 3 coated with ampicillin (W+A), WO 3 coated with penicillin (P+W), and WO 3 coated with ciprofloxacin (C+W). Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray spectroscopy (EDX), Fourier transforms infrared spectroscopy (FTIR), Rrman spectroscopy, and UV–visible spectroscopy were used to characterize synthesized nanoparticles. The minimum inhibitory concentration of C+W nanobiotic against S. aureus , E. coli , and mixed culture (S. aureus + E. coli) was lower than that of P+W and A+W. The impact of incubation period showed significant differences for each of nanobiotic against S. aureus , E. coli , and mixed culture. However, there were also non-significant differences among incubation periods for antibacterial activity of nanobiotics. It was pertinent to note that percentage variation in susceptibility of S. aureus with respect to mixed culture remained higher as compared to E. coli, indicating it stronger candidate imposing resistance. This paper thus suggested the strategy of coating of antibiotics with with WO 3 nanoparticles as an ideal combination for resistance modulation against single and mixed culture bacteria. [Display omitted] • Tungsten oxide nanoparticles successfully coupled with antibiotics. • Nanoparticles coupled antibiotics revealed appealing characteristics. • Ciprofloxacin coupling proved to be significant antibacterial compared to others. • S. aureus showed highest sensitivity compared to E. coli & mixed culture infection. • E. coli showed higher resistance than to S. aureus in mixed culture infection. [ABSTRACT FROM AUTHOR]

The SulA protein of Escherichia coli and related bacteria interacts directly with FtsZ, blocking cell division by disrupting Z-ring formation, yet the precise mechanism remains not fully understood. Previous demonstrations of Pseudomonas aeruginosa SulA's dimerization capability were confined to X-ray crystallography and lacked confirmation under in vivo conditions. Additionally, uncertainty persisted regarding the dimerization potential of E. coli's SulA protein. This paper employs a bacterial two-hybrid system to establish that both P. aeruginosa and E. coli SulA proteins indeed possess the capacity for dimerization. [Display omitted] • SulA proteins from E. coli and P. aeruginosa are capable of dimerization. • N-terminal fusion of Venus to E. coli SulA impairs dimerization of SulA. • SulA proteins from E. coli and P. aeruginosa demonstrate similar dimerization interfaces. [ABSTRACT FROM AUTHOR]

Due to high anthropogenic pressures, science-based coastal management required to ensure the sustainable use of coastal areas highly depends on environmental indicators used for decision-making. In this paper, we argue for the inclusion of Vibrio spp. abundance as a supplemental indicator of water quality for science-based coastal management by examining the environmental and bacterial indicators at a fish farm and a control site in Mali Ston Bay in the Adriatic Sea. Unexpectedly, heterotrophic bacteria, enterococci and Vibrio spp. were more abundant in the cold season, while E. coli and total coliforms, following a more traditional pattern, were more abundant in the warm season. Each of the currently used indicators has a specific purpose: heterotrophic bacteria indicate the presence of both nonpathogenic and pathogenic bacteria, while enterococci are pathogenic bacteria indicating fecal pollution. Vibrio spp. abundance additionally represents a non-fecal bacteria that can cause vibriosis in humans and aquatic organisms. Since vibriosis is the leading cause of disease-related fish mortality in aquaculture, pathogenic Vibrio spp. have large health and economic implications. These implications, as well as the added interpretative value when compared to other bacterial indicators, make Vibrio spp. abundance a good candidate as a water quality indicator. Significant dependence of the abundance on depth further differentiates Vibrio spp. from other indicators, thus bolstering the candidacy - especially in aquaculture areas. Before inclusion of any Vibrio spp. indicators into legislature, further research is needed particularly into (i) abundance thresholds characterizing water quality, and (ii) identification of species whose abundance should be monitored for best estimate of the disease risks. [Display omitted] • Analysis of environmental and bacterial indicators revealed no difference between fish farm and control. • Contrary to expectations, heterotrophic bacteria and Vibrio spp. thrived in the cold season. • Vibrio spp. abundance provides additional information on water quality and health risks. • Vibrio spp. could indicate poor water quality, even when other indicators suggest the quality is excellent. [ABSTRACT FROM AUTHOR]

[Display omitted] • New brominated TPT3 derivatives were designed and synthesized. • The brominated TPT3 bases can decrease the mispairing with natural bases. • The in vitro replication fidelity of d2-bromo-TPT3-dNaM is shown to be higher than d TPT3-dNaM for the first time. • The in vivo replication fidelity of d2-bromo-TPT3-dNaM is shown close to TPT3-dNaM in the specific sequence context, but a higher in the random sequence context. The high fidelity poses a central role in developing unnatural base pairs (UBPs), which means the high pairing capacity of unnatural bases with their partners, and low mispairing with all the natural bases. Different strategies have been used to develop higher-fidelity UBPs, including optimizing hydrophobic interaction forces between UBPs. Variant substituent groups are allowed to fine tune the hydrophobic forces of different UBPs' candidates. However, the modifications on the skeleton of TPT3 base are rare and the replication fidelity of TPT3-NaM remains hardly to improve so far. In this paper, we reasoned that modifying and/or expanding the aromatic surface by Bromo-substituents to slightly increase hydrophobicity of TPT3 might offer a way to increase the fidelity of this pair. Based on the hypothesis, we synthesized the bromine substituted TPT3, 2-bromo-TPT3 and 2, 4-dibromo-TPT3 as the new TPT3 analogs. While the enzyme reaction kinetic experiments showed that d2-bromo-TPT3-dNaM pair and d2, 4-dibromo-TPT3TP-dNaM pair had slightly less efficient incorporation and extension rates than that of dTPT3-dNaM pair, the assays did reveal that the mispairing of 2-bromo-TPT3 and 2, 4-dibromo-TPT3 with all the natural bases could dramatically decrease in contrast to TPT3. Their lower mispairing capacity promoted us to run polymerase chain amplification reactions, and a higher fidelity of d2-bromo-TPT3-dNaM pair could be obtained with 99.72 ± 0.01% of the in vitro replication fidelity than that of dTPT3-dNaM pair, 99.52 ± 0.09%. In addition, d2-bromo-TPT3-dNaM can also be effectively copied in E. coli cells, which showed the same replication fidelity as that of dTPT3-dNaM in the specific sequence, but a higher fidelity in the random sequence context. [ABSTRACT FROM AUTHOR]

The current study aimed to determine if the 3D-printing speed and temperature would impact the transferability of foodborne pathogens from the stainless-steel (SS) food cartridge to the 3D-printed food ink. Staphylococcus aureus and Escherichia coli were inoculated onto the interior surface of the SS food cartridges. Subsequently, a model food ink was extruded with a recommended macronutrient contribution of 55.8, 23.7, and 20.5% of carbohydrates, proteins, and fat, respectively. The impact of 3D-printing temperatures and speeds on transfer rates was analysed using a Two-Way ANOVA. S. aureus was transferred more from the cartridge to the food ink with a population of 3.39, 2.98, and 3.09 log CFU/g compared to 2.03, 2.06, and 2.00 log CFU/g for E. coli at 2000, 3000, and 4000 mm/s printing speed, respectively, at 25 °C. A Kruskal-Wallis Test was employed to investigate the effect of different speeds and temperatures on the transferability of S. aureus and E. coli. Speed was the main factor affecting S. aureus transferability, while temperature (25 and 50 °C) had the greatest impact on E. coli transferability. This research seeks to advance the understanding of 3D-printing parameters in pathogen transferability and help the food industry move towards this technology's quick and safe adoption. • Bacterial transfer from the cartridge to the food ink was species-specific at 25 °C. • The highest transferability for E. coli was presented at 50 °C. • Speed was the main factor influencing S. aureus transferability to the food ink. • 25 and 50 °C significantly increased the transfer rates of E. coli. [ABSTRACT FROM AUTHOR]

The food industry must prevent food contamination caused by pathogenic Escherichia coli , as they pose a severe public health threat globally, hence the need to explore new antimicrobial materials. In this paper, spermidine capped carbon dots (S-PCDs) were synthesized by hydrothermal reaction, and the antibacterial effects against E. coli and multi-drug resistant E. coli (MREC) was determined, so as to explore their potential application as antibacterial nanomaterials. The minimum inhibitory concentration values of S-PCDs against E. coli and MREC were 64 μg/mL and 128 μg/mL, respectively, showing strong antibacterial activity. The antibacterial zone was increased significantly with the increasing content of S-PCDs (p < 0.05). The results of bacteriostatic curve and bactericidal curve of S-PCDs on E. coli and MREC also showed that S-PCDs had a concentration-dependent inhibition on bacteria. In addition, the intrinsic antibacterial mechanism indicated that the antibacterial action of S-PCDs may involve cell membrane damage and reactive oxygen species production. During 30 days of exposure, S-PCDs showed persistent antibacterial effect against both E. coli and MREC without detectable resistance, especially without triggering secondary resistance in MREC. S-PCDs has potential application value in foodborne diseases caused by complex bacteria and even drug-resistant bacteria. • The antibacterial high-cationic (S-PCDs) were synthesized by a hydrothermal method. • S-PCDs had antibacterial activity against E. coli and multidrug resistant E. coli. • The antibacterial mechanism of CDs was related to membrane damage and ROS production. • S-PCDs did not trigger detectable secondary resistance in multidrug resistant E. coli. [ABSTRACT FROM AUTHOR]

Water polluted by pharmaceutically active compounds (PhACs) and water-borne pathogens urgently need to develop eco-friendly and advanced water treatment techniques. This paper evaluates the potential of using calcium peroxide (CaO 2), a safe and biocompatible oxidant both PhACs (thiamphenicol, florfenicol, carbamazepine, phenobarbital, and primidone) and pathogens (Escherichia coli, Staphylococcus aureus) in water. This paper evaluates the potential of using calcium peroxide (CaO 2) as a safe and biocompatible oxidant to remove both PhACs (thiamphenicol, florfenicol, carbamazepine, phenobarbital, and primidone) and pathogens (Escherichia coli , Staphylococcus aureus) in water. The increased CaO 2 dosage increased efficiencies of PhACs attenuation and pathogens inactivation, and both exhibited pseudo-first-order degradation kinetics (R2 > 0.90). PhACs attenuation were mainly via oxidization (H 2 O 2 , •OH/O•−, and O 2 •−) and alkaline hydrolysis (OH−) from CaO 2. Moreover, concentrations of these reactive species and their contributions to PhACs attenuation were quantified, and mechanistic model was established and validated. Besides, possible transformation pathways of target PhACs except primidone were proposed. As for pathogen indicators, the suitable inactivation dosage of CaO 2 was 0.1 g L−1. The oxidability (18–64%) and alkalinity (82–36%) generated from CaO 2 played vital roles in pathogen inactivation. In addition, CaO 2 at 0.01–0.1 g L−1 can be applied in remediation of SW contaminated by PhACs and pathogenic bacteria, which can degrade target PhACs with efficiencies of 21–100% under 0.01 g L−1 CaO 2 , and inactivate 100% of test bacteria under 0.1 g L−1 CaO 2. In short, capability of CaO 2 to remove target PhACs and microbial pathogens reveals its potential to be used as a representative technology for the advanced treatment of waters contaminated by organic compounds and microbial pathogens. • CaO2 in-situ remediated surface water contaminated by PhACs and bacteria. • HRS (H2O2, OH –̇OH, and O2 –) from CaO2 hydrolysis played main roles • Determine [HRS] and its second-order reaction rate constant with PhAC (k HRS,C). • Mechanistic modeling can predict PhACs attenuation within 25% deviation. • Degradation pathways of target PhACs were proposed. [ABSTRACT FROM AUTHOR]

Water polluted by pharmaceutically active compounds (PhACs) and water-borne pathogens urgently need to develop eco-friendly and advanced water treatment techniques. This paper evaluates the potential of using calcium peroxide (CaO 2), a safe and biocompatible oxidant both PhACs (thiamphenicol, florfenicol, carbamazepine, phenobarbital, and primidone) and pathogens (Escherichia coli, Staphylococcus aureus) in water. This paper evaluates the potential of using calcium peroxide (CaO 2) as a safe and biocompatible oxidant to remove both PhACs (thiamphenicol, florfenicol, carbamazepine, phenobarbital, and primidone) and pathogens (Escherichia coli , Staphylococcus aureus) in water. The increased CaO 2 dosage increased efficiencies of PhACs attenuation and pathogens inactivation, and both exhibited pseudo-first-order degradation kinetics (R2 > 0.90). PhACs attenuation were mainly via oxidization (H 2 O 2 , •OH/O•−, and O 2 •−) and alkaline hydrolysis (OH−) from CaO 2. Moreover, concentrations of these reactive species and their contributions to PhACs attenuation were quantified, and mechanistic model was established and validated. Besides, possible transformation pathways of target PhACs except primidone were proposed. As for pathogen indicators, the suitable inactivation dosage of CaO 2 was 0.1 g L−1. The oxidability (18–64%) and alkalinity (82–36%) generated from CaO 2 played vital roles in pathogen inactivation. In addition, CaO 2 at 0.01–0.1 g L−1 can be applied in remediation of SW contaminated by PhACs and pathogenic bacteria, which can degrade target PhACs with efficiencies of 21–100% under 0.01 g L−1 CaO 2 , and inactivate 100% of test bacteria under 0.1 g L−1 CaO 2. In short, capability of CaO 2 to remove target PhACs and microbial pathogens reveals its potential to be used as a representative technology for the advanced treatment of waters contaminated by organic compounds and microbial pathogens. • CaO2 in-situ remediated surface water contaminated by PhACs and bacteria. • HRS (H2O2, OH –̇OH, and O2 –) from CaO2 hydrolysis played main roles • Determine [HRS] and its second-order reaction rate constant with PhAC (k HRS,C). • Mechanistic modeling can predict PhACs attenuation within 25% deviation. • Degradation pathways of target PhACs were proposed. [ABSTRACT FROM AUTHOR]

The bacterial synthesis of copper nanoparticles emerges as an eco-friendly alternative to conventional techniques since it comprises a single-step and bottom-up approach, which leads to stable metal nanoparticles. In this paper, we studied the biosynthesis of Cu-based nanoparticles by Rhodococcus erythropolis ATCC4277 using a pre-processed mining tailing as a precursor. The influence of pulp density and stirring rate on particle size was evaluated using a factor-at-time experimental design. The experiments were carried out in a stirred tank bioreactor for 24 h at 25 °C, wherein 5% (v/v) of bacterial inoculum was employed. The O 2 flow rate was maintained at 1.0 L min−1 and the pH at 7.0. Copper nanoparticles (CuNPs), with an average hydrodynamic diameter of 21 ± 1 nm, were synthesized using 25 g.L−1 of mining tailing and a stirring rate of 250 rpm. Aiming to visualize some possible biomedical applications of the as-synthesized CuNPs, their antibacterial activity was evaluated against Escherichia coli and their cytotoxicity was evaluated against Murine Embryonic Fibroblast (MEF) cells. The 7-day extract of CuNPs at 0.1 mg mL−1 resulted in 75% of MEF cell viability. In the direct method, the suspension of CuNPs at 0.1 mg mL−1 resulted in 70% of MEF cell viability. Moreover, the CuNPs at 0.1 mg mL−1 inhibited 60% of E. coli growth. Furthermore, the NPs were evaluated regarding their photocatalytic activity by monitoring the oxidation of methylene blue (MB) dye. The CuNPs synthesized showed rapid oxidation of MB dye, with the degradation of approximately 65% of dye content in 4 h. These results show that the biosynthesis of CuNPs by R. erythropolis using pre-processed mine tailing can be a suitable method to obtain CuNPs from environmental and economical perspectives, resulting in NPs useful for biomedical and photocatalytic applications. [Display omitted] • R. erythropolis ATCC 4277 synthesized Cu-based nanoparticles from mining tailings. • Mouse Embryonic Fibroblast showed cell viability against Cu nanoparticle extract. • Bionanomining was improved by using mild conditions of pulp density and agitation. • Biosynthesized nanoparticles presented antibacterial activity against E. coli cells. • Organic contaminant (methylene blue dye) was oxidized by the Cu nanoparticles. [ABSTRACT FROM AUTHOR]

Increased environmental pollution is a critical issue that must be addressed. Photocatalytic, adsorption, and membrane filtration methods are suitable in environmental governance because of their high selectivity, low cost, environment-friendly nature, and excellent treatment efficiency. Graphitic carbon nitride (g-C 3 N 4) quantum dots (QDs) have been considered as photocatalysts, adsorbents, and membrane materials for wastewater treatments, owing to their stability, adsorption capacity, photochemical properties, and low toxicity and cost. This review summarizes g-C 3 N 4 QD synthesis techniques, operating parameters affecting the removal performance in the treatment process, modification effects with other semiconductors, and benefits and drawbacks of g-C 3 N 4 QD-based materials. Furthermore, this review discusses the practical applications of g-C 3 N 4 QDs as adsorbents, photocatalysts, and membrane materials for organic and inorganic contaminant treatments and their value-added product formation potential. Modified g-C 3 N 4 QD-based material adsorbents, photocatalysts, and membranes present potentially applicable effects, such as removal of most waterborne contaminants. Excellent results were obtained for the reduction of methyl orange, bisphenol A, tetracycline, ciprofloxacin, phenol, rhodamine B, E. coli , and Hg. Overall, this paper provides comprehensive background on g-C 3 N 4 QD-based materials and their diverse applications in wastewater treatment, and it presents a foundation for the enhancement of similar unique materials in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Easy and costless fabrication of CuONPs using Phragmites australis leaf extract. • Spherical shaped nanoparticles in sizes between 70 and 142 nm. • Excellent antimicrobial activity against both Gram (−) and Gram (+) bacteria. • Successful decolorization of Brilliant Blue R-250. • Molecular docking analysis of antibacterial activities of CuONPs. The demand for metal nanoparticles is increasing with the widening application areas while causing environmental impact including pollution, toxic byproduct generation and depletion of natural resources. Incorporating natural materials in nanoparticle synthesis can contribute toward environmental sustainability. This paper is concerned with the biogenic synthesis of copper oxide nanoparticles (CuONPs) mediated by the plant species Phragmites australis. UV–vis, FT-IR, TEM and SEM studies were used to characterize the obtained CuONPs. The synthesized nanoparticles' antibacterial efficacy against Escherichia coli and Staphylococcus aureus was assessed. The CuONPs' reducing power, total phenolic component content, and flavonoid content were all calculated. Additionally, the dye removal abilities of copper oxide nanoparticles using Brilliant Blue R-250 were studied. The CuONP synthesis was assessed morphological by change of color and in the UV–vis analysis by the SPR band around 320 and 360 nm. FT-IR was used to monitor the functional groups present in the synthesized CuONPs. The obtained CuONPs were spherical and between 70 and 142 nm in size, according to the SEM data and TEM analyses were in accordance with SEM results. Using disk diffusion, the CuONPs demonstrated substantial antibacterial efficacy against S. aureu s and E. coli , with inhibition zones of 18.5 ± 0.8 and 12.7 ± 0.6 mm, respectively. The MBC and MIC values were 62.5 μg/mL against S. aureus and 125 μg/mL against E. coli. The antioxidant abilities of P. australis and CuONPs were also confirmed. The CuONP solution's total phenolic substance content was 9.44 μg of pyrocathecol equivalent per milligram of nanoparticle, and its total flavonoid content was 16.24 μg of catechin equivalent per milligram of nanoparticle. Additionally, the synthesized CuONPs were found to be well effective on industrial dye removal by demonstrating high decolorization of 98 %. Also, the antibacterial activity of CuONPs was investigated through the interactions with S. aureus FtsZ, dihydropteroate synthase and thymidylate kinase. In silico molecular docking analysis was applied in the confirmation of the binding sites and interactions of active sites. CuONP showed −9.067, −8,048, and −7.349 kcal/mol of binding energies in molecular docking analysis of FtsZ, dihydropteroate synthase and thymidylate kinase proteins respectively. The results of this study suggested the antimicrobial, antioxidant and decolorative effect of synthesized CuONPs that can be apply in multiple areas of R&D and industry. [ABSTRACT FROM AUTHOR]

The brown mussel Perna perna is a valuable fishing resource, primarily in tropical and subtropical coastal regions. Because of their filter-feeding habits, mussels are directly exposed to bacteria in the water column. Escherichia coli (EC) and Salmonella enterica (SE) inhabit human guts and reach the marine environment through anthropogenic sources, such as sewage. Vibrio parahaemolyticus (VP) is indigenous to coastal ecosystems but can be harmful to shellfish. In this study, we aimed to assess the protein profile of the hepatopancreas of P. perna mussel challenged by introduced - E. coli and S. enterica - and indigenous marine bacteria - V. parahaemolyticus. Bacterial-challenge groups were compared with non-injected (NC) and injected control (IC) - that consisted in mussels not challenged and mussels injected with sterile PBS-NaCl, respectively. Through LC-MS/MS proteomic analysis, 3805 proteins were found in the hepatopancreas of P. perna. From the total, 597 were significantly different among conditions. Mussels injected with VP presented 343 proteins downregulated compared with all the other conditions, suggesting that VP suppresses their immune response. Particularly, 31 altered proteins - upregulated or downregulated - for one or more challenge groups (EC, SE, and VP) compared with controls (NC and IC) are discussed in detail in the paper. For the three tested bacteria, significantly different proteins were found to perform critical roles in immune response at all levels, namely: recognition and signal transduction; transcription; RNA processing; translation and protein processing; secretion; and humoral effectors. This is the first shotgun proteomic study in P. perna mussel, therefore providing an overview of the protein profile of the mussel hepatopancreas, focused on the immune response against bacteria. Hence, it is possible to understand the immune-bacteria relationship at molecular levels better. This knowledge can support the development of strategies and tools to be applied to coastal marine resource management and contribute to the sustainability of coastal systems. [Display omitted] • A total of 3805 proteins were found in the hepatopancreas of P. perna mussel. • Vibrio parahaemolyticus seems to be virulent and suppresses P. perna immune response. • E. coli and S. enterica triggered a general immune response against bacteria. • Proteins altered in response to all challenge-bacteria were vital for immune defense. • This study points out critical proteins against bacteria, promising for biotechnology. [ABSTRACT FROM AUTHOR]

[Display omitted] Pickering emulsions, defined as emulsions that are stabilized by colloidal particles, provide dispersion stability by preventing coalescence of the dispersed phase. In this study, we used a bifunctional hairy nanocellulose (BHNC) bearing both aldehyde and carboxylic acid groups as an stabilizer. We hypothesize that these particles as Pickering stabilizers can effectively reside at the oil–water interface, better than hairy nanocelluloses containing only carboxyl groups or aldehyde groups, and provide long-term stability without the need of any surfactants. Varying concentrations of BHNC were tested to explore the optimal concentration that provides emulsion stability. The effects of various preparation conditions such as salt and pH were also studied. Finally, carvacrol, an antibacterial essential oil, was loaded in the oil phase to develop antibacterial emulsions. It was shown that a 1% BHNC suspension provides 90% and 80% stability for a duration of 30 and 60 days, respectively. A theoretical model using nuclear magnetic resonance relaxometry data is developed to prove that only a monolayer of BHNC covers oil droplets. Increasing the concentration of BHNC decreased the size of oil droplets, which as a result increases the surface area available for monolayer coverage. It was also shown that the antibacterial emulsions are highly effective against Gram-negative (i.e. E. coli) and Gram-positive (i.e. S. aureus) bacteria. Accordingly, BHNC as a highly functionalized bio-derived colloidal particle opens new opportunities for engineering highly stable Pickering emulsions. [ABSTRACT FROM AUTHOR]

N,N -dimethyltryptamine (DMT), 5-methoxy- N,N- dimethyltryptamine (5-MeO-DMT) and 5-hydroxy- N,N -dimethyltryptamine (bufotenine) are psychedelic tryptamines found naturally in both plants and animals and have shown clinical potential to help treat mental disorders, such as anxiety and depression. Advances in both metabolic and genetic engineering make it possible to engineer microbes as cell factories to produce DMT and its aforementioned derivatives to meet demand for ongoing clinical study. Here, we present the development of a biosynthetic production pathway for DMT, 5-MeO-DMT, and bufotenine in the model microbe Escherichia coli. Through the application of genetic optimization techniques and process optimization in benchtop fermenters, the in vivo production of DMT in E. coli was observed. DMT production with tryptophan supplementation reached maximum titers of 74.7 ± 10.5 mg/L under fed batch conditions in a 2-L bioreactor. Additionally, we show the first reported case of de novo production of DMT (from glucose) in E. coli at a maximum titer of 14.0 mg/L and report the first example of microbial 5-MeO-DMT and bufotenine production in vivo. This work provides a starting point for further genetic and fermentation optimization studies with the goal to increase methylated tryptamine production metrics to industrially competitive levels. • First example of recombinant production of DMT, 5-MeO-DMT, and Bufotenine. • Genetic optimization shows high sensitivity to changes in transcriptional landscape. • Human INMT shows higher functional activity than Ephedra sinica PaNMT in E. coli. • High pH sensitivity of INMT limits production in well plate applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The size of silver nanoparticles (Ag NPs) and loading amount of Ag NPs onto their substrate/carrier are two key factors for their efficient applications. Herein, we present a facile method for in situ synthesizing ultrafine and highly loaded Ag NPs on the surface of tannin-coated catechol-formaldehyde resin (TA-CFR) nanospheres. TA-CFR nanospheres act as green and highly efficient reducing agents for converting silver ions (Ag+) into Ag NPs, and the size of resultant Ag NPs is only ∼ 7.5 nm, and the Ag NPs loading capacity of TA-CFR is as high as 61.5 wt%, both of which contribute to the very high specific surface area of Ag NPs. Consequently, the as-synthesized TA-CFR@Ag composites show high catalytic performance, and the catalytic rate for the reduction of 4-nitrophenol is almost 10 times higher than that of the control. Meanwhile, TA-CFR@Ag composites also possess high antibacterial activity, efficiently inhibiting the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Furthermore, tannin coating (thickness: ∼ 15 nm) minimizes the aggregation of Ag NPs, and enhances the reusability and stability of resultant Ag NPs, because of their high surface charges (the zeta potential is up to −65.5 ± 1.9 mV) and strong coordination capability with Ag NPs. This work provides a new frontier to develop multifunctional nanomaterials focusing on the green catalyst synthesis and environmental-remedy applications. [ABSTRACT FROM AUTHOR]