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MMWR. Morbidity and Mortality Weekly... Feb 2024
Topics: Humans; Vibrio vulnificus; Hot Temperature; Vibrio Infections
PubMed: 38300849
DOI: 10.15585/mmwr.mm7304a3 -
BioRxiv : the Preprint Server For... Jan 2024CRISPRi (Clustered Regularly Interspaced Palindromic Repeats interference) is a gene knockdown method that uses a deactivated Cas9 protein (dCas9) that binds a specific...
CRISPRi (Clustered Regularly Interspaced Palindromic Repeats interference) is a gene knockdown method that uses a deactivated Cas9 protein (dCas9) that binds a specific gene target locus dictated by an encoded guide RNA (sgRNA) to block transcription. Mobile-CRISPRi is a suite of modular vectors that enable CRISPRi knockdowns in diverse bacteria by integrating IPTG-inducible and genes into the genome using Tn transposition. Here, we show that the Mobile-CRISPRi system functions robustly and specifically in multiple species: , and . We demonstrate efficacy by targeting both essential and non-essential genes that function to produce defined, measurable phenotypes: bioluminescence, quorum sensing, cell division, and growth arrest. We anticipate that Mobile-CRISPRi will be used in species to systematically probe gene function and essentiality in various behaviors and native environments.
PubMed: 38293084
DOI: 10.1101/2024.01.17.575898 -
International Journal of Biological... Jan 2024A novel AMP Lc1773, derived from centrosomal protein of 192 kDa (Cep192), was isolated from Larimichthys crocea using a Bacillus subtilis system. After cDNA libraries...
A novel AMP Lc1773, derived from centrosomal protein of 192 kDa (Cep192), was isolated from Larimichthys crocea using a Bacillus subtilis system. After cDNA libraries construction, repeating selection of B. subtilis system, extraction of extracellular protein, and expression of recombinant protein, we found that B. subtilis 1773, extracellular protein, and rLc1773 had a strong potential to kill Vibrio. parahaemolyticus and V. vulnificus. Further analysis of the antibacterial mechanism revealed that rLc1773 not only disrupted the integrity of bacterial membrane (as confirmed by SEM, TEM, and confocal microscopy observation, and flow cytometry assays), resulting in bacterial cell membrane pore conformation, bacterial rupture, and leakage of cellular contents, but also targeted to block protein synthesis rather than damage nucleic acids (as confirmed by SDS-PAGE, enzyme expression, and gel retardation assays). In addition, rLc1773 had the ability to kill parasite Scuticociliatida in a high rate and low concentration. Critically, the antibacterial activity of rLc1773 had good thermal stability and UV radiation tolerance, but it was affected by pH 9-11 and diverse enzyme to some extent. Lc1773 had neither hemolysis on fish, shrimp, and rabbit erythrocytes,nor significant cytotoxicity. To our knowledge, Cep192 fragment was first demonstrated to possess bactericidal and parasiticidal activities.
Topics: Animals; Rabbits; Perciformes; Anti-Bacterial Agents; Vibrio parahaemolyticus; Fishes; Seafood
PubMed: 38287570
DOI: 10.1016/j.ijbiomac.2023.127744 -
BMC Microbiology Jan 2024Vibrio vulnificus exists as one of the most serious foodborne pathogens for humans, and rapid and sensitive detection methods are needed to control its infections. As an...
BACKGROUND
Vibrio vulnificus exists as one of the most serious foodborne pathogens for humans, and rapid and sensitive detection methods are needed to control its infections. As an emerging method, The Loop-Mediated Isothermal Amplification (LAMP) assay has been applied to the early detection of various foodborne pathogens due to its high efficiency, but sample preprocessing still prolongs the complete detection. To optimize the detection process, our study established a novel sample preprocessing method that was more efficient compared to common methods.
RESULT
Using V. vulnificus as the detecting pathogen, the water-lysis-based detecting LAMP method shortened the preprocessing time to ≤ 1 min with 100% LAMP specificity; the detection limits of the LAMP assay were decreased to 1.20 × 10 CFU/mL and 1.47 × 10 CFU/g in pure culture and in oyster, respectively. Furthermore, the 100% LAMP specificity and high sensitivity of the water-lysis method were also obtained on detecting V. parahaemolyticus, V. alginolyticus, and P. mirabilis, revealing its excellent LAMP adaption with improvement in sensitivity and efficiency.
CONCLUSION
Our study provided a novel LAMP preprocessing method that was more efficient compared to common methods and possessed the practical potential for LAMP application in the future.
Topics: Humans; Vibrio vulnificus; Nucleic Acid Amplification Techniques; Water; Specimen Handling; Sensitivity and Specificity; Molecular Diagnostic Techniques
PubMed: 38279108
DOI: 10.1186/s12866-024-03186-8 -
Foods (Basel, Switzerland) Jan 2024The bioactive properties of the combination of microencapsulated cell-free supernatant (CFS) from and thyme extract on food-related bacteria (, ATCC29213, ATCC29212,...
The bioactive properties of the combination of microencapsulated cell-free supernatant (CFS) from and thyme extract on food-related bacteria (, ATCC29213, ATCC29212, and Paratyphi A NCTC13) were investigated. The microencapsulated CFS of in combination with ethanolic thyme extract, had a particle size in the range of 1.11 to 11.39 µm. The microencapsulated CFS of had a wrinkled, spherical form. In the supernatant, especially at 2% (), the thyme extract additive caused a decrease in the wrinkled form and a completely spherical structure. A total of 11 compounds were determined in the cell-free supernatant of , and acetic acid (39.64%) and methyl-d3 1-dideuterio-2-propenyl ether (10.87%) were the main components. Thyme extract contained seven components, the main component being carvacrol at 67.96% and 1,2,3-propanetriol at 25.77%. Significant differences ( < 0.05) were observed in the inhibition zones of the extracts on bacteria. The inhibitory effect of thyme extract on bacteria varied between 25.00 () and 41.67 mm (). Less antibacterial activity was shown by the microencapsulated CFS from compared to their pure form. ( < 0.05). As a result, it was found that microencapsulated forms of CFS from especially those prepared in combination with 2% (/) thyme extract, generally showed higher bioactive effects on bacteria.
PubMed: 38275696
DOI: 10.3390/foods13020329 -
The Journal of Antimicrobial... Feb 2024Most human infections caused by Vibrio spp. do not warrant antimicrobial treatment but in severe cases, targeted antimicrobial treatment can be lifesaving. For Vibrio...
OBJECTIVES
Most human infections caused by Vibrio spp. do not warrant antimicrobial treatment but in severe cases, targeted antimicrobial treatment can be lifesaving. For Vibrio spp., standardized antimicrobial susceptibility testing (AST) guidelines with EUCAST methodology are lacking. In this study, we aimed to produce data suitable for EUCAST to establish clinical MIC breakpoints and zone diameter correlates for Vibrio spp.
METHODS
An intercontinental collection (N = 524) comprising five important Vibrio spp. (V. alginolyticus, V. cholerae, V. fluvialis, V. parahaemolyticus and V. vulnificus) was organized. All isolates were subjected to broth microdilution (BMD) against 11 antimicrobial agents according to ISO 20776-1 using unsupplemented Mueller-Hinton broth on freeze-dried Sensititre panels (Thermo Scientific, UK), and most isolates (n = 371) were also tested with disc diffusion according to EUCAST methodology for non-fastidious organisms.
RESULTS
Aggregated results were used to generate MIC and zone diameter distributions and to prepare graphs of MIC-zone diameter correlation. Based on these results, the EUCAST Steering Committee determined clinical susceptible (S) and resistant (R) MIC (mg/L) breakpoints (S≤/R>) for the five Vibrio spp. for piperacillin/tazobactam (1/1), cefotaxime (0.25/0.25), ceftazidime (1/1), meropenem (0.5/0.5), ciprofloxacin (0.25/0.25), levofloxacin (0.25/0.25), azithromycin (4/4), doxycycline (0.5/0.5) and trimethoprim/sulfamethoxazole (0.25/0.25). The corresponding zone diameter breakpoints were identified.
CONCLUSIONS
We demonstrated the validity of using standard BMD and EUCAST disc diffusion methodology for AST of five Vibrio spp., and generated suitable data to allow EUCAST to determine clinical MIC and zone diameter breakpoints for five pathogenic Vibrio spp., including both non-toxigenic and toxigenic V. cholerae.
Topics: Humans; Anti-Bacterial Agents; Microbial Sensitivity Tests; Meropenem; Ceftazidime; Vibrio
PubMed: 38158720
DOI: 10.1093/jac/dkad391 -
Annals of Agricultural and... Dec 2023The aim of the study was to explore the correlation between characteristics of microbial community, pathogenic bacteria and high-risk antibiotic-resistant genes, between...
OBJECTIVE
The aim of the study was to explore the correlation between characteristics of microbial community, pathogenic bacteria and high-risk antibiotic-resistant genes, between coastal beaches and a multi-warm-blooded host, as well as to determine potential species biomarkers for faecal source contamination on tropical coastal beaches in China.
MATERIAL AND METHODS
The 'One-Health' approach was used in a microbiological study of beaches and warm-blooded hosts. The microbial.community was analyzed using 16S rRNA gene amplicons and shotgun metagenomics on Illumina NovaSeq.
RESULTS
The Chao, Simpson, Shannon, and ACE indices of non-salt beach were greater than those of salt beaches at the genus and OTU levels (P < 0.001). Bacteroidota, Halanaerobiaeota, Cyanobacteria, and Firmicutes were abundant on salt beaches (P<0.01). Human-sourced microorganisms were more abundant on salt beaches, which accounted for 0.57%. and were considered as reliable indicators for the contamination of human faeces. High-risk carbapenem-resistant Klebsiella pneumoniae and the genotypes KPC-14 and KPC-24 were observed on salt beaches. Tet(X3)/tet(X4) genes and four types of MCR genes co-occurred on beaches and humans; MCR9.1 accounted for the majority. Tet(X4) found among Cyanobacteria. Although rarely reported at Chinese beaches, pathogens, such as ,, and , were observed.
CONCLUSIONS
The low microbial community diversity, however, did not indicate a reduced risk. The transfer of high-risk ARGs to extreme coastal environments should be given sufficient attention.
Topics: Humans; RNA, Ribosomal, 16S; Water Microbiology; Bacteria; Anti-Bacterial Agents; Microbiota
PubMed: 38153067
DOI: 10.26444/aaem/176090 -
International Microbiology : the... Dec 2023Tectona grandis Linn, commonly known as teak, is traditionally used to treat a range of diseases, including the common cold, headaches, bronchitis, scabies, diabetes,...
Tectona grandis Linn, commonly known as teak, is traditionally used to treat a range of diseases, including the common cold, headaches, bronchitis, scabies, diabetes, inflammation, and others. The present study was conducted with the purpose of isolating and identifying the active compounds in T. grandis leaf against a panel of Vibrio spp., which may induce vibriosis in shrimp, using bioassay-guided purification. The antimicrobial activity was assessed using the microdilution method, followed by the brine shrimp lethality assay to determine toxicity. Following an initial screening with a number of different solvents, it was established that the acetone extract was the most effective. The acetone extract was then exposed to silica gel chromatography followed by reversed-phase HPLC and further UHPLC-orbitrap-ion trap mass spectrometry to identify the active compounds. Three compounds called 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin were identified with substantial anti-microbial action against V. parahaemolyticus, V. alginolyticus, V. harveyi, V. anguillarum, and V. vulnificus. The IC values of the three compounds viz. 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin varied between 2 and 28, 7 and 38, and 7 and 56 μg/mL, respectively, which are as good as the standard antibiotics such as amoxicillin and others. The in vivo toxicity test revealed that the compounds were non-toxic to shrimp. The results of the study suggest that T. grandis leaf can be used as a source of bioactive compounds to treat Vibrio species in shrimp farming.
PubMed: 38151632
DOI: 10.1007/s10123-023-00468-5 -
Frontiers in Cellular and Infection... 2023Our patient, a 48-year-old man from Guangdong's coastal region, worked selling and processing oysters and other seafood. He started experiencing swelling and pain in his...
Our patient, a 48-year-old man from Guangdong's coastal region, worked selling and processing oysters and other seafood. He started experiencing swelling and pain in his left knee on October 4, 2022, and they got worse over time. The findings of mNGS test showed Vibrio vulnificus infection. The patient had AIDS, hepatitis A and hepatitis B concurrently. He was admitted to the hospital's intensive care unit (ICU) for treatment as his symptoms worsened. We refrained from performing an amputation because the family members expressed a desire to keep the limb. The limb was managed with regular dressing changes, thorough debridement, wound closure, ongoing VSD drainage, and local antibiotic irrigation. The patient's organ function eventually returned to normal, and the systemic infection got better. On November 1, the wound's new granulation tissue had grown well and had gradually crept to cover 80% of the wound. The tissue's blood flow had also improved, indicating a trend of growth and healing.
Topics: Male; Humans; Middle Aged; Vibrio vulnificus; Coinfection; Vibrio Infections; Hepatitis B; Hepatitis C; HIV Infections
PubMed: 38146312
DOI: 10.3389/fcimb.2023.1290636 -
Protein Science : a Publication of the... Mar 2024Vibrio vulnificus (vv) is a multidrug-resistant human bacterial pathogen whose prevalence is expected to increase over the years. Transketolases (TK), transferases...
Vibrio vulnificus (vv) is a multidrug-resistant human bacterial pathogen whose prevalence is expected to increase over the years. Transketolases (TK), transferases catalyzing two reactions of the nonoxidative branch of the pentose-phosphate pathway and therefore linked to several crucial metabolic pathways, are potential targets for new drugs against this pathogen. Here, the vvTK is crystallized and its structure is solved at 2.1 Å. A crown of 6 histidyl residues is observed in the active site and expected to participate in the thiamine pyrophosphate (cofactor) activation. Docking of fructose-6-phosphate and ferricyanide used in the activity assay, suggests that both substrates can bind vvTK simultaneously. This is confirmed by steady-state kinetics showing a sequential mechanism, on the contrary to the natural transferase reaction which follows a substituted mechanism. Inhibition by the I38-49 inhibitor (2-(4-ethoxyphenyl)-1-(pyrimidin-2-yl)-1H-pyrrolo[2,3-b]pyridine) reveals for the first time a cooperative behavior of a TK and docking experiments suggest a previously undescribed binding site at the interface between the pyrophosphate and pyridinium domains.
Topics: Humans; Transketolase; Vibrio vulnificus; Kinetics; Cooperative Behavior; Thiamine Pyrophosphate; Transferases
PubMed: 38145310
DOI: 10.1002/pro.4884