To achieve uniform soluble expression of multiple proteins in the same Escherichia coli strain, and simplify the process steps of antigen production in genetic engineering subunit multivalent vaccine, we co-expressed three avian virus proteins including the fowl adenovirus serotype 4 (FAdV-4) Fiber-2 protein, infectious bursal disease virus (IBDV) VP2 protein and egg-drop syndrome virus (EDSV) Fiber protein in E. coli BL21(DE3) cells after optimization of gene codon, promoter, and tandem expression order. The purified proteins were analyzed by Western blotting and agar gel precipitation (AGP). The content of the three proteins were well-proportioned after co-expression and the purity of the purified proteins were more than 80%. Western blotting analysis and AGP experiment results show that all the three co-expression proteins had immunoreactivity and antigenicity. It is the first time to achieve the three different avian virus antigens co-expression and co-purification, which simplified the process of antigen production and laid a foundation for the development of genetic engineering subunit multivalent vaccine.
Animals ; Antigens, Viral/genetics* ; Biological Assay ; Chickens/immunology* ; Escherichia coli/genetics* ; Infectious bursal disease virus/immunology* ; Poultry Diseases ; Vaccines, Synthetic/isolation & purification* ; Viral Structural Proteins/immunology* ; Viral Vaccines/immunology*

Stomatal density is important for crop yield. In this paper, we studied the epidermal pattern factors (EPFs) related to stomatal development. Prokaryotic expression vectors were constructed to obtain EPFs. Then the relationship between EPFs and hydrogen sulfide (H2S) was established. First, AtEPF1, AtEPF2 and AtEPFL9 were cloned and constructed to pET28a vectors. Then recombinant plasmids pET28a-AtEPF1, pET28a-AtEPF2 and pET28a-AtEPFL9 were digested and sequenced, showing successful construction. Finally, they were transformed into E. coli BL21(DE3) separately and induced to express by isopropyl β-D-galactoside (IPTG). The optimized expression conditions including IPTG concentration (0.5, 0.3 and 0.05 mmol/L), temperature (28 °C, 28 °C and 16 °C) and induction time (16 h, 16 h and 20 h) were obtained. The bands of purified proteins were about 18 kDa, 19 kDa and 14.5 kDa, respectively. In order to identify their function, the purified AtEPF2 and AtEPFL9 were presented to Arabidopsis thaliana seedlings. Interestingly, the H2S production rate decreased or increased compared with the control, showing significant differences. That is, EPFs affected the production of endogenous H2S in plants. These results provide a foundation for further study of the relationship between H2S and EPFs on stomatal development, but also a possible way to increase the yield or enhance the stress resistance.
Arabidopsis ; genetics ; metabolism ; Arabidopsis Proteins ; genetics ; isolation & purification ; metabolism ; Escherichia coli ; genetics ; Genetic Vectors ; genetics ; Hydrogen Sulfide ; metabolism ; Plasmids ; genetics ; Seedlings ; metabolism

Emerging antibiotic resistance is a major global health threat. The analysis of nucleic acid sequences linked to susceptibility phenotypes facilitates the study of genetic antibiotic resistance determinants to inform molecular diagnostics and drug development. We collected genetic data (11,087 newly-sequenced whole genomes) and culture-based resistance profiles (10,991 out of the 11,087 isolates comprehensively tested against 22 antibiotics in total) of clinical isolates including 18 main species spanning a time period of 30 years. Species and drug specific resistance patterns were observed including increased resistance rates for Acinetobacter baumannii to carbapenems and for Escherichia coli to fluoroquinolones. Species-level pan-genomes were constructed to reflect the genetic repertoire of the respective species, including conserved essential genes and known resistance factors. Integrating phenotypes and genotypes through species-level pan-genomes allowed to infer gene-drug resistance associations using statistical testing. The isolate collection and the analysis results have been integrated into GEAR-base, a resource available for academic research use free of charge at https://gear-base.com.
Acinetobacter baumannii ; genetics ; isolation & purification ; Bacteria ; genetics ; isolation & purification ; Cell Culture Techniques ; methods ; Drug Resistance, Microbial ; genetics ; Escherichia coli ; genetics ; isolation & purification ; Genome, Bacterial ; Genotype ; Humans ; Internet ; Microbial Sensitivity Tests ; Phenotype ; Whole Genome Sequencing

OBJECTIVE: To develop methods of extraction and purification of Cterminal NUDT9 homology domain of human transient receptor potential melastatin 2 (TRPM2) channel. METHODS: After sonication and centrifuge of strain Rosetta (DE3) which was induced by isopropylthio-β-D-galactoside, GST-NUDT9-H was collected after the binding of supernatant with GST beads and eluted with reduced glutathione. Then the elution buffer containing fusion protein was purified by size exclusion chromatography after concentration and centrifuge. Finally, with the cleavage of thrombin and binding with the GST beads, NUDT9-H with high purity in supernatant was collected. RESULTS: The GST-NUDT9-H fusion protein was stabilized with lysis buffer containing 0.5% n-dodecyl -β-d-maltoside (DDM), and wash buffer containing 0.025% DDM in size-exclusion chromatography system, and finally the NUDT9-H with high purity was obtained after cleaved by thrombin (1 U/2 mg fusion protein) for 24 h. CONCLUSIONS Due to the poor stability of NUDT9-H, it is necessary to add DDM in extraction and purification buffer to stabilize the conformation of NUDT9-H, so as to increase its yields and purity.
Escherichia coli ; genetics ; Glucosides ; chemistry ; Humans ; Protein Domains ; Protein Stability ; Pyrophosphatases ; chemistry ; genetics ; isolation & purification ; Recombinant Fusion Proteins ; chemistry ; isolation & purification ; TRPM Cation Channels ; chemistry ; isolation & purification ; Thrombin ; metabolism

BACKGROUND: Bacterial contamination of drinking water is a major public health problem in rural areas of sub-Saharan Africa. Unimproved water sources are a major reservoir of Escherichia coli (E. coli) causing severe diarrhoea in humans. This study assessed E. coli counts in drinking water from different sources and their relationship with water source protection status and neighbourhood sanitation and hygiene practices in rural villages of Mohale Basin in Lesotho. METHODS: Thirty drinking water sources were purposively sampled and their water analysed for E. coli counts. The types of water sources, their protection status and neighbourhood sanitation and hygiene practices in their proximity were also assessed. E. coli counts in water samples were compared to water source protection status, neighbourhood sanitation, hygiene practices, livestock faeces and latrine proximity to water sources. RESULTS: E. coli counts were found in all water samples and ranged from less than 30 colony-forming units (cfu)/100 ml to 4800 cfu/100 ml in protected sources to 43,500,000 cfu/100 ml in unprotected sources. A significant association between E. coli counts in drinking water samples and lack of water source protection, high prevalence of open defecation (59%, n = 100), unhygienic practices, livestock faeces and latrine detections in proximity to water sources was found in the study (P < 0.05). CONCLUSION Water sources in studied villages were contaminated with faeces and posed a health risk to consumers of that water. Community-led sanitation and hygiene education and better water source protection are urgently needed.
Drinking Water ; microbiology ; Escherichia coli ; isolation & purification ; Feces ; microbiology ; Health Behavior ; Humans ; Hygiene ; Lesotho ; Rural Health ; Sanitation ; methods ; statistics & numerical data ; Water Microbiology ; Water Quality ; Water Supply ; statistics & numerical data

By using an RAD peptide display system derived from the ATPase domain of recombinase RadA of Pyrococcus furiosus, an anti-hCG antibody-like molecule was prepared by grafting an hCG-binding peptide to the RAD scaffold. After linking to sfGFP gene, a gene of hCG peptide-grafted RAD was synthesized and cloned into a bacterial expression vector (pET30a-RAD/hCGBP-sfGFP). The vector was transformed into Escherichia coli, and expression of the fusion protein was induced. After isolation and purification of the fusion protein, its binding affinity and specificity to hCG were determined by using a process of immunoabsorption followed by GFP fluorescence measurement. A comparison of hCG-binding activity with a similarly grafted single-domain antibody based on a universal scaffold was performed. The measurement of hCG-binding affinity and specificity revealed that the grafted RAD has an optimally high binding affinity and specificity to hCG, which are better than the grafted single-domain antibody. Moreover, the affinity and specificity of grafted RAD molecule are comparable to those of a commercial monoclonal antibody. In addition, the hCG-binding peptide-grafted RAD molecule has a relatively high biochemical stability, making it a good substitute for antibody with potential application.
Antibodies, Monoclonal ; chemistry ; isolation & purification ; metabolism ; Antibody Specificity ; DNA-Binding Proteins ; genetics ; metabolism ; Escherichia coli ; genetics ; Escherichia coli Proteins ; metabolism ; Humans ; Peptides ; Recombinant Fusion Proteins ; genetics ; metabolism

Pectobacterium carotovorum subsp. carotovorum is one of the world's top ten plant pathogens, mainly infecting cruciferous economic crops and ornamental flowers. In this study, an antibacterial gene cpxP (Gene ID: 29704421) was cloned from the genome of Pectobacterium carotovorum subsp. carotovorum, and constructed on the prokaryotic expression plasmid pET-15b, and the recombinant plasmid was transformed into Escherichia coli BL21 (DE3), then stability and bacteriostatic experiments of the purified CpxP protein were performed. The final concentration of IPTG was 1 mmol/L, obtaining high-efficiency exogenous expression of the CpxP protein. There was no other protein after purification, and the destined protein exhibited good thermal stability and pH stability. The antibacterial test results showed that the inhibition rate of the CpxP protein on carrot slice was 44.89% while the inhibition rate on potato slice was 59.41%. To further explain its antibacterial mechanism, studying the spatial structure of this protein can provide new ideas for the control of soft rot and new protein pesticide targets.
Anti-Bacterial Agents ; pharmacology ; Bacteria ; drug effects ; Bacterial Proteins ; isolation & purification ; pharmacology ; Escherichia coli ; genetics ; Membrane Proteins ; isolation & purification ; pharmacology ; Pectobacterium carotovorum ; genetics ; metabolism ; Plasmids ; genetics

OBJECTIVETo investigated the anti-inflammatory and antimicrobial effects of anthocyanins extracted from black soybean on the chronic bacterial prostatitis (CBP) rat model.

METHODSThe Sprague-Dawley rats were divided into 4 groups, including control, ciprofloxacin, anthocyanins and anthocyanins with ciprofloxacin groups (n=8 in each group). Then, drip infusion of bacterial suspension (Escherichia coli Z17 O:K:H) into Sprague-Dawley rats was conducted to induce CBP. In 4 weeks, results of prostate tissue, urine culture, and histological analysis on the prostate were analyzed for each group.

RESULTSThe use of ciprofloxacin, anthocyanins, and anthocyanins with ciprofloxacin showed statistically significant decreases in bacterial growth and improvements in the reduction of prostatic inflammation compared with the control group (P<0.05). The anthocyanins with ciprofloxacin group showed a statistically significant decrease in bacterial growth and improvement in prostatic inflammation compared with the ciprofloxacin group (P<0.05).

CONCLUSIONSThese results suggest that anthocyanins may have anti-inflammatory and antimicrobial effects, as well as a synergistic effect with ciprofloxacin. Therefore, we suggest that the combination of anthocyanins and ciprofloxacin may be effective in treating CBP to obtain a higher rate of treatment success.

Acinar Cells ; drug effects ; pathology ; Animals ; Anthocyanins ; isolation & purification ; pharmacology ; therapeutic use ; Anti-Infective Agents ; pharmacology ; therapeutic use ; Anti-Inflammatory Agents ; pharmacology ; therapeutic use ; Chronic Disease ; Disease Models, Animal ; Escherichia coli Infections ; drug therapy ; urine ; Fibrosis ; Inflammation ; pathology ; Male ; Plant Extracts ; pharmacology ; therapeutic use ; Prostate ; drug effects ; microbiology ; pathology ; Prostatitis ; drug therapy ; microbiology ; urine ; Rats, Sprague-Dawley ; Severity of Illness Index ; Soybeans ; chemistry ; Urine ; microbiology

Mechanosensitive (MS) channels are extensively studied membrane protein for maintaining intracellular homeostasis through translocating solutes and ions across the membrane, but its mechanisms of channel gating and ion selectivity are largely unknown. Here, we identified the YnaI channel as the Na/K cation-selective MS channel and solved its structure at 3.8 Å by cryo-EM single-particle method. YnaI exhibits low conductance among the family of MS channels in E. coli, and shares a similar overall heptamer structure fold with previously studied MscS channels. By combining structural based mutagenesis, quantum mechanical and electrophysiological characterizations, we revealed that ion selective filter formed by seven hydrophobic methionine (YnaI) in the transmembrane pore determined ion selectivity, and both ion selectivity and gating of YnaI channel were affected by accompanying anions in solution. Further quantum simulation and functional validation support that the distinct binding energies with various anions to YnaI facilitate Na/K pass through, which was defined as binding-block mechanism. Our structural and functional studies provided a new perspective for understanding the mechanism of how MS channels select ions driven by mechanical force.
Cryoelectron Microscopy ; Escherichia coli Proteins ; chemistry ; isolation & purification ; metabolism ; ultrastructure ; Ion Channels ; chemistry ; isolation & purification ; metabolism ; ultrastructure ; Mechanotransduction, Cellular ; Models, Molecular ; Quantum Theory

ObjectiveTo evaluate the effect of cefoxitin prophylactic in reducing the incidence of severe infection after transrectal prostate biopsy (TRPB).

METHODSThis retrospective study included 155 cases of TRPB with a 5-day administration of oral levofloxacin at 200 mg bid (the control group) and another 167 cases with a 3-day administration of oral levofloxacin at the same dose plus intravenous cefoxitin at 2.0 g 2 hours before TRPB (the experimental group) according to the distribution characteristics of drug-resistance bacteria in our department. The patients of the control and experimental groups were aged (68.68 ± 8.12) and (68.72 ± 7.51) years, with PSA levels of (19.78 ± 21.57) and (21.15 ± 42.63) μg/L, involving (11.68 ± 1.44) and (11.77±1.02) biopsy cores, respectively. Comparisons were made between the two groups of patients in the incidence rate of severe infection, which was defined as lower urinary track symptoms plus the systemic inflammatory response syndrome (SIRS) within 7 days after TRPB.

RESULTSThe incidence rate of postoperative severe infection was significantly lower in the experimental group than in the control (0.6% ［1/167］ vs 5.8% ［9/155］, P < 0.05). Blood cultures revealed positive E-coli strains in 6 cases in the control group, including 5 ESBL-positive and 4 quinolone-resistant and amikacin-sensitive cases, all sensitive to cefoxitin, cefoperazone/sulbactam and imipenem. The only one case of severe infection was shown to be negative in blood culture.

CONCLUSIONSPreoperative intravenous administration of cefoxitin according to the specific distribution characteristics of drug-resistance bacteria can significantly reduce the incidence of severe infection after TRPB.

Aged ; Anti-Bacterial Agents ; therapeutic use ; Biopsy ; adverse effects ; methods ; Cefoxitin ; therapeutic use ; Drug Resistance, Bacterial ; Escherichia coli ; isolation & purification ; Escherichia coli Infections ; microbiology ; prevention & control ; Humans ; Levofloxacin ; therapeutic use ; Male ; Middle Aged ; Postoperative Complications ; blood ; prevention & control ; Prostate ; pathology ; Retrospective Studies