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Four new rufomycins, compounds

The aim of this study was to screen the lactic acid bacteria for fermentation of adlay bran and evaluate the anti-wrinkle effect of fermented and non-fermented adlay bran.Adlay bran was fermented with candidate LAB and extracted with 70% ethanol. The extracts from LAB-fermented adlay bran and non-fermented adlay bran were evaluated for the anti-wrinkle effects by measuring the hyaluronan, collagen, and elastin production in cells using ELISA kit. The molecular anti-wrinkle mechanism was investigated by RT-qPCR. Furthermore, the antioxidant activity, total phenolic and flavonoid content were also determined.Among the tested LAB, Lactobacillus brevis MJM60390 was selected for the highest glycosidase activity. Both extracts from adlay bran (NFAB) and L. brevis MJM60390-fermented adlay bran (LBFAB) showed anti-wrinkle effect, and LBFAB showed higher activity. Compared with control, hyaluronan production was increased by 24.73% and 59.38%, collagen production was increased by -13.08% and 34.19%, and the elastin production was increased by 29.78% and 53.73% by NFAB and LBFAB treatment, respectively. Investigation on the mRNA expression showed that LBFAB upregulated the expression of Has 2 and Has 3 and downregulate HYAL1 and HYAL2. LBFAB also upregulated the mRNA expression of COL1A1, COL1A2, ELN and inhibited the expression of collagenase and elastase. However, not all of these genes were regulated by NFAB. Furthermore, the antioxidant activity was significantly increased after fermentation, and the content of the phenolic and flavonoid compounds also increased in the LBFAB.In this study, we demonstrated that fermentation of adlay bran with L. brevis MJM60390 enhanced the anti-wrinkle activity through increasing the hyaluronan synthesis in keratinocytes and improving collagen and elastin production in dermal fibroblasts.

Fermentation is a traditional technique used to increase nutrients, flavonoids, vitamins, minerals, and the flavor of raw materials. In this study, adlay bran was fermented by Lactobacillus brevis MJM60390 (FAB), and the anti-melanogenic effect was investigated. The results demonstrated that FAB significantly suppressed melanin accumulation in mouse melanogenic B16F10 cells, and the activity was higher than non-fermented adlay bran (NFAB). The molecular mechanism study showed that FAB inhibited melanin synthesis by suppressing the gene expression of melanocortin 1 receptor (Mc1r), melanocyte-inducing transcription factor (Mitf), tyrosinase (Tyr), tyrosinase-related protein-1 (Trp-1), and tyrosinase-related protein-2 (Trp-2) genes. Western blotting analysis showed that FAB strongly decreased the expression of Tyr, Trp-1, and Trp-2 compared to NFAB. Furthermore, phenolic compounds such as gallic acid, p-coumaric acid, ferulic acid, and sinapic acid, which are known for their anti-melanogenic effects, were significantly increased in FAB compared with NFAB. These findings suggest that FAB holds great potential as an anti-melanogenic agent and can be used for the development of whitening cosmetics.

Ferulic acid is known to be a water-insoluble compound present in many fruits and vegetables and is known to possess antioxidant, anti-cancer, and anti-inflammatory properties. They are quickly absorbed in the stomach and metabolized in the liver. Their colonic exposure is found to be low due to their quick absorption and metabolism in the upper gastrointestinal tract, and due to this reason, only a small fraction of FA found in a bound form is associated with the insoluble and soluble fiber of the food matrix reaching the colon. Here we describe the synthesis and characterization of ferulic acid (FA) bound to fructo oligosaccharide (FOS) rendering the resultant FA-FOS conjugate water soluble, resistant to gastrointestinal digestion and absorption, along with the capability to deliver a therapeutically meaningful dose of FA to the large intestine. Free FA is released from FA-FOS conjugate by the digestive action of gut microflora, and the pharmacokinetic profile and pharmacodynamics are evaluated in a rat model. The efficacy of FA-FOS conjugate in the delivery of FA to the large intestine and its accumulation in tumours were evaluated in colitis induced colon cancer model and their efficacy through plasma bioavailability is determined in xenograft mice model carrying tumour from human colon cancer cells. The accumulation of FA derived from FA-FOS conjugate in the tumour was demonstrated by the MALDI imaging technique. The major metabolites of FA-FOS conjugate in plasma were determined through a data-dependent MS/MS experiment of precursor ion scan, utilizing triple quad (QTRAP) equipped LC-MS.

Background and purposeFerulic acid exhibit anticancer activity but almost most of the free ferulic acid taken orally are absorbed in the stomach and extensively metabolised by the liver and hence hardly any free ferulic acid reach the large intestine to exert its beneficial activity. Fructo-oligosaccharide (dietary fibre) are resistant to gastro-intestinal enzymes and are poorly absorbed by the stomach but bioavailable in the large intestine where they are digested by gut microbiota. Ferulic acid fructo-oligosaccharide conjugate was synthesized which could self-assemble in to disc shaped amorphous microparticles, it was found to be resistant to gastro-intestinal enzymes and digestion by gut microbiota. The synthesized microparticles could be used for targeted delivery to the colon and accessed for its ability to ameliorate colo-rectal cancer and inflammation.Experimental approachThe anti-cancer activity of the FA FOS microparticle (FA FOS I) was tested in human colon cancer cell lines HT29, LoVo and compared with the toxicity to normal human colon fibroblast CCD18-Co, relative to that of conventional chemotherapeutic colon cancer drug oxaliplatin. The apoptosis induction by FA FOS I was assessed by TUNNEL (Terminal deoxynucleotidyl transferase mediated dUTP Nick-end Labelling) and FACS. The ability of the FA FOS microparticle to induce cell cycle arrest was determined. The gene expression profiling of both apoptosis related genes and cell cycle arrest related genes were analysed by using RT-PCR analysis of an array of apoptosis related genes and cell cycle related genes. In-vivo pre-clinical anti-colorectal cancer studies of FA FOS I microparticle were carried out in AOM-DSS mediated colitis associated colon cancer mice model (AOM DSS CAC) to determine its anti-cancer efficacy in the physiological, immunological and innate host microbiota setting.Key resultsThe in-vitro studies in colon cancer and normal colon cells exhibited selective cytotoxicity and apoptosis induction in colon cancer cells. The microparticle arrested the cell cycle in the G0-G1phase. There was a reduction in 60.83% of tumour lesions in FA FOS I treated group compared to control group. The H&E histochemistry of the colon tissue revealed that there was 48.27% reduction in the malignant cell or tumour cells in the colon tissue on treatment with FA FOS I. The FA FOS conjugate treatment enhanced the gut barrier function and tight junction with the intestinal barrier guarded by the mucosal lining. The immunohistochemistry (IHC) and the immunofluorescence of the mouse colon tissue revealed the suppression of inflammation and related inflammatory cytokines in the colon. The inhibition of cell proliferation, up-regulation of tumour suppressor protein and apoptosis of the malignant or tumour cells were detected and quantified by IHC and TUNEL staining. The evaluation of immune status of the AOM DSS CAC mouse treated with FA FOS I microparticle was determined using haematological analysis of the blood lymphocytes which revealed a 9% increase in WBC count and the multiplex immunofluorescence of the colon tissue revealed an increase in the infiltration of T-helper cells and cytotoxic T-cells into the tumour microenvironment followed by the cells of the innate immune system. There was a considerable decrease in the expression of tumour suppressing PD-L1 by the tumour cells on four weeks treatment with FA FOS I microparticle.Conclusion and implicationsAll these data implicate better efficacy of the FA FOS I microparticle delivery to colon and amelioration of colo-rectal cancer, inflammation, and positive immune modulation of tumour microenvironment against tumour proliferation.

Streptomyces coelicolor is a filamentous soil bacterium producing several kinds of antibiotics. S. coelicolor abs8752 is an abs ( a nti b iotic s ynthesis deficient)-type mutation at the absR locus; it is characterized by an incapacity to produce any of the four antibiotics synthesized by its parental strain J1501. A chromosomal DNA fragment from S. coelicolor J1501, capable of complementing the abs- phenotype of the abs8752 mutant, was cloned and analyzed. DNA sequencing revealed that two complete ORFs (SCO6992 and SCO6993) were present in opposite directions in the clone. Introduction of SCO6992 in the mutant strain resulted in a remarkable increase in the production of two pigmented antibiotics, actinorhodin and undecylprodigiosin, in S. coelicolor J1501 and abs8752. However, introduction of SCO6993 did not show any significant difference compared to the control, suggesting that SCO6992 is primarily involved in stimulating the biosynthesis of antibiotics in S. coelicolor. In silico analysis of SCO6992 (359 aa, 39.5 kDa) revealed that sequences homologous to SCO6992 were all annotated as hypothetical proteins. Although a metalloprotease domain with a conserved metal-binding motif was found in SCO6992, the recombinant rSCO6992 did not show any protease activity. Instead, it showed very strong β-glucuronidase activity in an API ZYM assay and toward two artificial substrates, p-nitrophenyl-β-D-glucuronide and AS-BI-β-D-glucuronide. The binding between rSCO6992 and Zn2+ was confirmed by circular dichroism spectroscopy. We report for the first time that SCO6992 is a novel protein with β-glucuronidase activity, that has a distinct primary structure and physiological role from those of previously reported β-glucuronidases.

To investigate the molecular characteristics of human respiratory syncytial virus (HRSV) detected in Gyeonggi Province from 2015/16 to 2017/18, 2331 specimens from patients with sporadic acute respiratory illness and 85 specimens from four HRSV outbreaks in the postpartum care center were analyzed by real-time reverse transcription PCR. HRSVs were detected in 97 of the 2416 (4.0%) specimens, and among the positive specimens, 38 (39.2%) were identified as HRSV-A and 59 (60.8%) as HRSV-B. During the study periods, HRSV-B predominated in all seasons, except in 2016/17 during which HRSV-A predominated. Depending on the age groups, HRSV prevalence was the highest in 0- to 2-year-old patients. Comparison of noninfected subjects with HRSV-infected subjects revealed that HRSV infection more frequently resulted in fever, nasal obstruction, and wheezing, although the frequency of sore throat was low; however, comparison of the symptoms between HRSV-A- and HRSV-B-infected patients revealed no significant differences in symptoms. Phylogenetic analysis showed that all HRSV-A patients had an ON1 genotype, and all HRSV-B patients had an BA9 genotype. These results provide a valuable reference regarding the circulating pattern and molecular characterization of HRSV. Continuous monitoring will be essential to detect newly emerging HRSV genotypes.

Rufomycin and ilamycin are synonymous for the same class of cyclopeptides, currently encompassing 33 structurally characterized isolates and 9 semisynthetic derivatives. Elucidation of new structures prioritized the consolidation of the names and established the structures of four diastereoisomeric rufomycins with a 2-piperidinone, named rufomycins 4–7, including full (1)H/(13)C NMR assignments. The characteristic HSQC cross-peak for the CH-5, the hemiaminal carbon in amino acid #5, allows assignment of the stereocenters C-4 and C-5 within this ring. Semisynthetic derivatives (rufomycinSS 1, 2, and 3) were prepared from a rufomycins 4 and 6 mixture to validate the structural assignments. Based on the X-ray crystal structures of rufomycins 2 and 4, considering the NMR differences of rufomycins 7 vs 4–6 compared to rufomycinSS 1 vs 2 and 3, and taking into account that two major conformers, A and B, occur in both rufomycinSS 2 and 3, structural modeling was pursued. Collectively, this paper discusses the NMR spectroscopic differences of the stereoisomers and their possible 3D conformers and correlates these with the anti-Mycobacterium tuberculosis activity. In addition, a look at the history prioritizes names and numbering schemes for this group of antibiotics and leads to consolidated nomenclature for all currently known members, natural and semisynthetic derivatives, and serves to accommodate future discoveries.

Lactic acid bacteria have been widely used as probiotics for improving gut health. However, studies on oral probiotics were very limited. In this study, 67 lactic acid bacteria (LAB) were isolated from fermented food and screened for antagonistic activity against Streptococcus mutans, the causative pathogen of dental caries. Leuconostoc mesenteroides MJM60376 showed the highest antagonistic activity against S. mutans KCTC3065. L. mesenteroides MJM60376 also showed oral probiotic characteristics including weak acid production, lysozyme tolerance, adhesion to oral epithelial cell (YD-38), antibiotic susceptibility, and good coaggregation ability with S. mutans. Furthermore, the biofilm formation of S. mutans was significantly reduced when cocultured with L. mesenteroides. Scanning electron microscopy analysis showed that amounts of attached bacteria of S. mutans and network-like structures were significantly reduced by L. mesenteroides MJM60376. Cell-free supernatant (CFS) of L. mesenteroides MJM60376 also greatly inhibited biofilm formation of S. mutans from the adherent stage, the activity remained even after it was treated with catalase, trypsin, or pH neutralized. Expression levels of biofilm formation-related genes were significantly reduced in S. mutans when it was treated with the CFS of L. mesenteroides MJM60376. Therefore, L. mesenteroides MJM60376 has great potential to be used as a multifunctional ingredient.

In this study, we isolated lactic acid bacteria that inhibit streptococcal biofilm from the oral cavity of infants and identified two novel compounds from the supernatant of their culture broth. The two compounds are structurally similar, and both consist of iminosugars, glycerol, and unsaturated fatty acid.

We previously reported that mature Bombyx mori silkworm (SW) ameliorated scopolamine (Sco)-induced amnesia, and Angelica gigas (AG) prevented cognitive impairment. SW is known for its gastroprotective effects such as improving liver function and alleviating the effects of Parkinson's disease. AG is known for its neuroprotective effects and for lowering the effects of low-density lipoprotein cholesterol. However, the neuroprotective effect of combined SW and AG (SWA-1) treatment and the underlying molecular mechanism by which SWA-1 regulates neurodegenerative diseases remains unclear. We evaluated the neuroprotective effect of SWA-1 against Sco-induced mild cognitive impairment in mice and H2O2-induced cell death in HT22 mouse hippocampal neuronal cells and elucidated the underlying molecular mechanism. Morris water maze and Y-maze tests were performed to examine the learning and memory abilities of mice. The underlying molecular mechanism was investigated by using western blotting. We demonstrated that SWA-1 significantly protects against H2O2-induced cell death in HT22 mouse hippocampal neuronal cells. SWA-1 also significantly reversed Sco-induced spatial learning and memory impairment. Specifically, SWA-1 upregulates the protein levels of phosphorylated extracellular signal-related kinase (Erk1/2) and phosphorylated p38 MAP kinase (p38). SWA-1 remarkably decreased the apoptotic index Bax/Bcl2 expression in the hippocampus of Sco-treated mice. Our results suggest that SWA-1 may be administered as alternative therapy for cognitive impairment and neurodegenerative diseases and should be studied further in human trials.

Thrombosis causes poor blood circulation, which may lead to several cardiovascular disorders. Antiplatelet aggregation and antihyperlipidemia are the key processes that improve blood circulation. The antiplatelet aggregation and antihyperlipidemic effects of ACG-1, a mixture of Angelica gigas, Cynanchum wilfordii, and Ginkgo biloba extracts, were investigated in this study. The antiplatelet aggregation activity of ACG-1 was determined by studying its effects on collagen-induced platelet aggregation in human platelet-rich plasma (PRP). In addition, the effects of ACG-1 were investigated in a thromboembolism mouse model. The high-fat diet (HFD)-fed mouse model was used to investigate the antihyperlipidemic effects of ACG-1 and western blotting assay was performed to elucidate its mechanism of action. It was observed that ACG-1 significantly inhibited platelet aggregation in human PRP. Furthermore, ACG-1 showed protective effects in a thromboembolism mouse model induced by administering a mixed collagen and epinephrine intravenous injection. Oral administration of ACG-1 also significantly ameliorated blood lipid profiles in the HFD-fed mouse model. In conclusion, ACG-1 should be considered a powerful functional food to improve blood circulation.

The global Tuberculosis (TB) rate continues to increase by 1% per year with the widespread of drug-resistant TB. Therefore, the development and research to find new anti-TB drugs are becoming an extremely urgent mission. To be able to screen lead anti-tuberculosis drugs, currently, researchers have to carry out directly on the cells of Mycobacterium tuberculosis and to be performed in bio-security facilities level 3 or 4, to prevent infection from pathogens. However, our results demonstrated that the screening of anti-TB drug candidates can be implemented in bio-security facilities level 1 laboratory with the Escherichia coli cell extraction and recombinant ClpC1 protein - an integral part of the Mycobacterium tuberculosis genome. We focused on the ATP hydrolysis activity of ClpC1 to create a specific research direction for the high-throughput anti-tuberculosis drug screening system. ClpC1 protein was overexpressed and purified with functionally characterized (93.5 kDa). The steady-state growth of recombinant ClpC1 protein in Luria-Bertani (LB) broth High Salt medium was maintained and stabilized after extraction. The determined ATPase activity of ClpC1 was performed by measuring the released phosphate from the reaction. Ecumicin was chosen to be a control compound with expected ATP hydrolysis activities (Hill coefficient = 1,19 ± 0,217; Kd value = 0,52 ± 0,275). We tested this high throughput screening system with ten anti-TB drugs to evaluate the effectiveness of our screening system. Based on these results, we built a complete high-throughput screening system anti-tuberculosis drug safety and quickly.

Hyperuricemia is a metabolic disorder caused by increased uric acid (UA) synthesis or decreased UA excretion. Changes in eating habits have led to an increase in the consumption of purine-rich foods, which is closely related to hyperuricemia. Therefore, decreased purine absorption, increased UA excretion, and decreased UA synthesis are the main strategies to ameliorate hyperuricemia. This study aimed to screen the lactic acid bacteria (LAB) with purine degrading ability and examine the serum UA-lowering effect in a hyperuricemia mouse model. As a result

The rapid and accurate diagnosis of infectious diseases with high morbidity rates is crucial because it can minimize the misuse and overuse of antibiotics and increase survival rates in dreadful conditions. The conventional antibiotic susceptibility test (AST) systems used to choose appropriate antibiotics require long wait times to obtain results and cannot prevent the misuse or overuse of antibiotics by clinicians who need to quickly treat patients and cannot wait to identify the underlying cause of their symptoms. Therefore, several rapid AST (rAST) methods have been developed to provide quick test results, but they are complicated to operate, require additional equipment or materials, and give less accurate results than the conventional AST methods. In this study, we propose an rAST method that can obtain precise outcomes from a simple process with a short running time using a bacterial isolation microwell-plug (μWELLplug) in a conventional 96-well plate. The specifically designed hydrogel component of the μWELLplug provides a simple process for cell isolation and the observation of bacterial growth and morphological changes induced by a variety of antibiotic concentrations. The μWELLplug is placed over each well of the 96-well plate, and then bacterial or eukaryotic cells are isolated in the microwells and treated with different antibiotic concentrations to observe their effects.

Comparison of the structures of ClpC1–ecumicin and ClpC1–rufomycin complexes reveals unique interactions that are relevant to their modes of action., The biological processes related to protein homeostasis in Mycobacterium tuberculosis, the etiologic agent of tuberculosis, have recently been established as critical pathways for therapeutic intervention. Proteins of particular interest are ClpC1 and the ClpC1–ClpP1–ClpP2 proteasome complex. The structure of the potent antituberculosis macrocyclic depsipeptide ecumicin complexed with the N-terminal domain of ClpC1 (ClpC1-NTD) is presented here. Crystals of the ClpC1-NTD–ecumicin complex were monoclinic (unit-cell parameters a = 80.0, b = 130.0, c = 112.0 Å, β = 90.07°; space group P21; 12 complexes per asymmetric unit) and diffracted to 2.5 Å resolution. The structure was solved by molecular replacement using the self-rotation function to resolve space-group ambiguities. The new structure of the ecumicin complex showed a unique 1:2 (target:ligand) stoichiometry exploiting the intramolecular dyad in the α-helical fold of the target N-terminal domain. The structure of the ecumicin complex unveiled extensive interactions in the uniquely extended N-terminus, a critical binding site for the known cyclopeptide complexes. This structure, in comparison with the previously reported rufomycin I complex, revealed unique features that could be relevant for understanding the mechanism of action of these potential antituberculosis drug leads. Comparison of the ecumicin complex and the ClpC1-NTD-L92S/L96P double-mutant structure with the available structures of rufomycin I and cyclomarin A complexes revealed a range of conformational changes available to this small N-terminal helical domain and the minor helical alterations involved in the antibiotic-resistance mechanism. The different modes of binding and structural alterations could be related to distinct modes of action.

Drug-resistant tuberculosis (TB) has lent urgency to finding new drug leads with novel modes of action. A high-throughput screening campaign of >65,000 actinomycete extracts for inhibition of Mycobacterium tuberculosis viability identified ecumicin, a macrocyclic tridecapeptide that exerts potent, selective bactericidal activity against M. tuberculosis in vitro , including nonreplicating cells. Ecumicin retains activity against isolated multiple-drug-resistant (MDR) and extensively drug-resistant (XDR) strains of M. tuberculosis . The subcutaneous administration to mice of ecumicin in a micellar formulation at 20 mg/kg body weight resulted in plasma and lung exposures exceeding the MIC. Complete inhibition of M. tuberculosis growth in the lungs of mice was achieved following 12 doses at 20 or 32 mg/kg. Genome mining of lab-generated, spontaneous ecumicin-resistant M. tuberculosis strains identified the ClpC1 ATPase complex as the putative target, and this was confirmed by a drug affinity response test. ClpC1 functions in protein breakdown with the ClpP1P2 protease complex. Ecumicin markedly enhanced the ATPase activity of wild-type (WT) ClpC1 but prevented activation of proteolysis by ClpC1. Less stimulation was observed with ClpC1 from ecumicin-resistant mutants. Thus, ClpC1 is a valid drug target against M. tuberculosis , and ecumicin may serve as a lead compound for anti-TB drug development.

The rise of multi- and extensively drug-resistant Mycobacterium tuberculosis (M. tb) strains and co-infection with human immunodeficiency virus has escalated the need for new anti-M. tb drugs. Numerous challenges associated with the M. tb, in particular slow growth and pathogenicity level 3, discouraged use of this organism in past primary screening efforts. From current knowledge of the physiology and drug susceptibility of mycobacteria in general and M. tb specifically, it can be assumed that many potentially useful drug leads were missed by failing to screen directly against this pathogen. This review discusses recent high-throughput phenotypic screening strategies for anti-M. tb drug discovery. Emphasis is placed on prioritization of hits, including their extensive biological and chemical profiling, as well as the development status of promising drug candidates discovered with phenotypic screening.

Nontuberculous mycobacterial pulmonary infection is often aggravated due to antibiotic resistance issues. There is a need for development of new drugs inducing both host immune responses and antimicrobial activities. This study shows that the rufomycins 4/5/6/7 (Rufomycin 4–7), which targets ClpC1 as a subunit of caseinolytic protein complex ClpC1/ClpP1/ClpP2 of mycobacteria, exhibits a dual effect in host innate defense and in vivo antimicrobial activities against a rough morphotype of Mycobacterium abscessus (Mabs-R), a clinically severe morphotype that causes hyperinflammation. Rufomycin 4–7 treatment showed antimicrobial effects against Mabs pulmonary infection in vivo and in macrophages. In addition, Rufomycin 4–7 significantly decreased inflammation, but enhanced the autophagy/lysosomal genes through upregulation of the nuclear translocation of transcription factor EB (TFEB). Furthermore, Rufomycin 4–7 treatment effectively inhibited mitochondrial damage and oxidative stresses in macrophages during Mabs-R infection. Collectively, Rufomycin 4–7-mediated dual effects inducing both antimicrobial activities and host immune defense might confer an advantage to treatment against Mabs-R infection.

Residual complexity (RC) involves the impact of subtle but critical structural and biological features on drug lead validation, including unexplained effects related to unidentified impurities. RC commonly plagues drug discovery efforts due to the inherent imperfections of chromatographic separation methods. The new diketopiperazine, rufomyazine (6), and the previously known antibiotic, rufomycin (7), represent a prototypical case of RC that (almost) resulted in the misassignment of biological activity. The case exemplifies that impurities well below the natural abundance of 13C (1.1%) can be highly relevant and calls for advanced analytical characterization of drug leads with extended molar dynamic ranges of >1:1,000 using qNMR and LC-MS. Isolated from an actinomycete strain, 6 was originally found to be active against Mycobacterium tuberculosis with a minimum inhibitory concentration (MIC) of 2 ��g/mL and high selectivity. As a part of lead validation, the dipeptide was synthesized and surprisingly found to be inactive. The initially observed activity was eventually attributed to a very minor contamination (0.24% [m/m]) with a highly active cyclic peptide (MIC ��� 0.02 ��M), subsequently identified as an analogue of 7. This study illustrates the serious implications RC can exert on organic chemistry and drug discovery, and what efforts are vital to improve lead validation and efficiency, especially in NP-related drug discovery programs.

Ecumicins are potent antituberculosis natural compounds produced by the rare actinomycete Nonomuraea sp. MJM5123. Here, we report an efficient genetic manipulation platform of this rare actinomycete. CRISPR/Cas9-based genome editing was achieved based on successful sporulation. Two genes in the ecumicin gene cluster were further investigated, ecuN and ecuE, which potentially encode a pretailoring cytochrome P450 hydroxylase and the core peptide synthase, respectively. Deletion of ecuN led to an enhanced ratio of the ecumicin compound EcuH16 relative to that of EcuH14, indicating that EcuN is indeed a P450 hydroxylase, and there is catalyzed hydroxylation at the C-3 position in unit12 phenylalanine to transform EcuH16 to the compound EcuH14. Furthermore, promoter engineering of ecuE by employing the strong promoter kasO*P was performed and optimized. We found that integrating the endogenous ribosome-binding site (RBS) of ecuE together with the RBS from kasO*P led to improved ecumicin production and resulted in a remarkably high EcuH16/EcuH14 ratio. Importantly, production of the more active component EcuH16 was considerably increased in the double RBSs engineered strain EPR1 compared to that in the wild-type strain, reaching 310 mg/L. At the same time, this production level was 2.3 times higher than that of the control strain EPA1 with only one RBS from kasO*P. To the best of our knowledge, this is the first report of genome editing and promoter engineering on the rare actinomycete Nonomuraea.

This study represents a systematic chemical and biological study of the rufomycin (RUF) class of cyclic heptapeptides, which our anti-TB drug discovery efforts have identified as potentially promising anti-TB agents that newly target the caseinolytic protein C1, ClpC1. Eight new RUF analogues, rufomycins NBZ1-NBZ8 (1-8), as well as five known peptides (9-13) were isolated and characterized from the Streptomyces atratus strain MJM3502. Advanced Marfey's and X-ray crystallographic analysis led to the assignment of the absolute configuration of the RUFs. Several isolates exhibited potent activity against both pathogens M. tuberculosis H37Rv and M. abscessus, paired with favorable selectivity (selectivity index >60), which collectively underscores the promise of the rufomycins as potential anti-TB drug leads.

Microbial cellulases have become the mainstream biocatalysts due to their complex nature and widespread industrial applications. Here, homogeneous endoglucanase GluCB31 from Bacillus subtilis subsp. inaquosorum CBS31 was studied. GluCB31 was purified to 17.68-fold with an 8.33% yield and a specific activity of 1066.37 U/mg. Biochemical properties of GluCB31 were performed and the results are as follows; molecular mass of 35 kDa with an optimum pH at 7.5 and temperature at 50°C. GluCB31 was immobilized in calcium alginate gel and it exhibited the highest activity at 10°C higher temperature than soluble enzyme, as the entrapment in alginate gel made GluCB31 more stable. Kinetic studies showed the Vmax of 1293.33 ± 2.51 U/mg and Km of 0.0183 mg/mL. Enzymatic activity was activated by Tween-20 (106.7%), Tween-80 (111.6%), Triton X-100 (142.3%), SDS (135.5%), Mg++ (185.7%), Cu++ (167.6%), Zn++ (153.7%), Mn++ (106.3%), Ba++ (181.9%), Ni++ (107.2%) while inhibited by Fe++ (15.8%), β-mercaptoethanol (46.8%), EDTA (54.5%). Enthalpy, free energy, and entropy of activation were calculated to be 38.526 kJmol-1, 44.187 kJmol-1, and -17.518 Jmol-1K-1 respectively. Also, ΔGE-S and ΔGE-T were found to be -10.75 kJmol-1 and -45.92 kJmol-1 respectively. A low ΔS, ΔGE-S, and ΔGE-T values were signified enzyme-catalyzed reaction occurs at a fast rate and the existence of the enzyme in its stable state. Cellobiose was the major end product of hydrolysis. These attributes of GluCB31 demonstrated the diversity of catalytic activities and serve in various biotechnological processes, thus deserve to be developed as a bio-industrial agent.

Cardiovascular diseases, such as stroke, are the most common causes of death in developed countries. Ischemic stroke accounts for 85% of the total cases and is caused by abnormal thrombus formation in the vessels, causing deficient blood and oxygen supply to the brain. Prophylactic treatments include the prevention of thrombus formation, of which the most used is acetylsalicylic acid (ASA), however, it is associated with a high incidence of side effects. Angelica gigas Nakai (AG) is a natural herb used to improve blood circulation via anti-platelet aggregation, one of the key processes involved in thrombus formation. We examined the antithrombotic effects of AGE 232, the ethanol extract of A. gigas Nakai. AGE 232 showed a significant reduction in death or paralysis in mice caused by collagen/epinephrine-induced thromboembolism in a dose-dependent manner and inhibition of collagen-induced human platelet aggregation in a concentration-dependent manner. Additionally, AGE 232-treated mice did not show severe bleeding in the gut compared to ASA-treated mice. AGE 232 resulted in a decrease in the number of neutrophils attached to the human umbilical vein endothelial cells (HUVECs) and lower inhibition of COX-1 in response to bleeding and damage to blood vessels, a major side effect of ASA. Therefore, AGE 232 can prevent thrombus formation and stroke.

We previously reported that mature