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Gut Pathogens Nov 2023We report a 36-year-old male patient died of V. vulnificus-induced septicaemia and multiple organ failure syndrome after oyster consumption at a restaurant. We isolated...
We report a 36-year-old male patient died of V. vulnificus-induced septicaemia and multiple organ failure syndrome after oyster consumption at a restaurant. We isolated and identified V. vulnificus vv16015 from the patient's blood sample and antibiotic susceptibility tests indicated sensitivity to all 21 antibiotics. Oyster samples were subsequently collected from the restaurant's supplier and three strains of V. vulnificus were isolated. Whole genome sequencing and analysis revealed vv16015 to be distantly related to these strains and confirmed that V. vulnificus contamination was present in the seafood of the restaurant and supplier. Using a Galleria mellonella larvae infection model, the virulence of vv16015 was determined to be higher than that of comparison strains isolated from a surviving patient (vv15018) and an oyster (vv220015). The human and environment distribution of V. vulnificus in Shenzhen is sporadic and heterogeneous, and vv16015 is highly virulent compared to other strains.
PubMed: 38007445
DOI: 10.1186/s13099-023-00580-x -
Microbiology Insights 2023
PubMed: 37954125
DOI: 10.1177/11786361231204672 -
MBio Oct 2023Changing climatic conditions influence parameters associated with the growth of pathogenic spp. in the environment and, hence, are linked to increased incidence of...
Changing climatic conditions influence parameters associated with the growth of pathogenic spp. in the environment and, hence, are linked to increased incidence of vibriosis. Between 1992 and 2022, a long-term increase in spp. infections was reported in Florida, USA. Furthermore, a spike in spp. infections was reported post Hurricane Ian, a category five storm that made landfall in Florida on 28 September 2022. During October 2022, water and oyster samples were collected from three stations in Lee County in an area significantly impacted by Ian. spp. were isolated, and whole-genome sequencing and phylogenetic analysis were done, with a focus on and to provide genetic insight into pathogenic strains circulating in the environment. Metagenomic analysis of water samples provided insight with respect to human health-related factors, notably the detection of approximately 12 pathogenic spp., virulence and antibiotic resistance genes, and mobile genetic elements, including the SXT/R391 family of integrative conjugative elements. Environmental parameters were monitored as part of a long-term time series analysis done using satellite remote sensing. In addition to anomalous rainfall and storm surge, changes in sea surface temperature and chlorophyll concentration during and after Ian favored the growth of spp. In conclusion, genetic analysis coupled with environmental data and remote sensing provides useful public health information and, hence, constitute a valuable tool to proactively detect and characterize environmental pathogens, notably vibrios. These data can aid the development of early warning systems by yielding a larger source of information for public health during climate change. Evidence suggests warming temperatures are associated with the spread of potentially pathogenic spp. and the emergence of human disease globally. Following Hurricane Ian, the State of Florida reported a sharp increase in the number of reported spp. infections and deaths. Hence, monitoring of pathogens, including vibrios, and environmental parameters influencing their occurrence is critical to public health. Here, DNA sequencing was used to investigate the genomic diversity of and , both potential human pathogens, in Florida coastal waters post Hurricane Ian, in October 2022. Additionally, the microbial community of water samples was profiled to detect the presence of spp. and other microorganisms (bacteria, fungi, protists, and viruses) present in the samples. Long-term environmental data analysis showed changes in environmental parameters during and after Ian were optimal for the growth of spp. and related pathogens. Collectively, results will be used to develop predictive risk models during climate change.
PubMed: 37931127
DOI: 10.1128/mbio.01476-23 -
Environmental Science and Pollution... Nov 2023Among the diverse Vibrio spp. autochthonous to coastal ecosystems, V. cholerae, V. fluvialis, V. vulnificus and V. parahaemolyticus are pathogenic to humans. Increasing...
Among the diverse Vibrio spp. autochthonous to coastal ecosystems, V. cholerae, V. fluvialis, V. vulnificus and V. parahaemolyticus are pathogenic to humans. Increasing sea-surface temperature, sea-level rise and water-related disasters associated with climate change have been shown to influence the proliferation of these bacteria and change their geographic distribution. We investigated the spatio-temporal distribution of Vibrio spp. in a tropical lake for 1 year at a 20-day interval. The abundance of Vibrio spp. was much higher during the south-west monsoon in 2018, when the lake experienced a once-in-a-century flood. The distribution of Vibrio spp. was influenced by salinity (r = 0.3, p < 0.001), phosphate (r = 0.18, p < 0.01) and nitrite (r = 0.16, p < 0.02) in the water. We isolated 470 colonies of Vibrio-like organisms and 341 could be revived further and identified using 16S rRNA gene sequencing. Functional annotations showed that all the 16 Vibrio spp. found in the lake could grow in association with animals. More than 60% of the isolates had multiple antibiotic resistance (MAR) index greater than 0.5. All isolates were resistant to erythromycin and cefepime. The proliferation of multiple antibiotic-resistant Vibrio spp. is a threat to human health. Our observations suggest that the presence of a diverse range of Vibrio spp. is favoured by the low-saline conditions brought about by heavy precipitation. Furthermore, infections caused by contact with Vibrio-contaminated waters may be difficult to cure due to their multiple antibiotic resistances. Therefore, continuous monitoring of bacterial pollution in the lakes is essential, as is the generation of risk maps of vibrio-infested waters to avoid public contact with contaminated waters and associated disease outbreaks.
Topics: Animals; Humans; Lakes; Ecosystem; RNA, Ribosomal, 16S; Vibrio; Vibrio cholerae; Drug Resistance, Microbial; Water; Anti-Bacterial Agents; Vibrio parahaemolyticus
PubMed: 37906329
DOI: 10.1007/s11356-023-30565-x -
Plants (Basel, Switzerland) Oct 2023This research comparatively investigates the in vitro antimicrobial activity of extracts from (pink water lily) leaves against pathogenic bacteria. The experimental...
This research comparatively investigates the in vitro antimicrobial activity of extracts from (pink water lily) leaves against pathogenic bacteria. The experimental extracts are aqueous, acetonic, and 95% ethanolic extracts; and the pathogenic bacteria being studied include , , , and , which are commonly found in freshwater fish and brackish aquatic animals. The ethanolic extract achieves the highest bacterial inhibitory effects against and . The minimum inhibitory concentrations of the ethanolic extract against and are 10 mg/mL; and 2.5 mg/mL against and . The ethanolic extract is effective against . The high-performance liquid chromatography results show that, in the phenolic acids group, gallic acid is the most dominant (0.600-3.21% /), followed by sinapic acid (0.37-0.83% /). In the flavonoids group, catechin is the most dominant (0.02-1.08% /), followed by rutin (0.002-0.03% /). Essentially, the ethanolic extract can potentially be used as a natural antibiotic agent to treat bacterial infections in fish and aquatic animals.
PubMed: 37896051
DOI: 10.3390/plants12203588 -
Microorganisms Oct 2023() and () are water- and foodborne bacteria that can cause several distinct human diseases, collectively called vibriosis. The success of oyster aquaculture is... (Review)
Review
() and () are water- and foodborne bacteria that can cause several distinct human diseases, collectively called vibriosis. The success of oyster aquaculture is negatively impacted by high abundances. Myriad environmental factors affect the distribution of pathogenic , including temperature, salinity, eutrophication, extreme weather events, and plankton loads, including harmful algal blooms. In this paper, we synthesize the current understanding of ecological drivers of and and provide a summary of various tools used to enumerate and in a variety of environments and environmental samples. We also highlight the limitations and benefits of each of the measurement tools and propose example alternative tools for more specific enumeration of pathogenic and . Improvement of molecular methods can tighten better predictive models that are potentially important for mitigation in more controlled environments such as aquaculture.
PubMed: 37894160
DOI: 10.3390/microorganisms11102502 -
Microorganisms Sep 2023This study aimed to determine the incidence and virulence factor profiling of species from hospital wastewater (HWW) and community wastewater effluents. Wastewater...
This study aimed to determine the incidence and virulence factor profiling of species from hospital wastewater (HWW) and community wastewater effluents. Wastewater samples from selected sites were collected, processed, and analysed presumptively by the culture dependent methods and molecular techniques. A total of 270 isolates were confirmed as genus delineating into (27%), (9.1%), (4.1%), and (3%). The remainder (>50%) may account for other species not identified in the study. The four species were isolated from secondary hospital wastewater effluent (SHWE), while was the sole specie isolated from Limbede community wastewater effluent (LCWE) and none of the four species was recovered from tertiary hospital wastewater effluent (THWE). However, several virulence genes were identified among isolates from SHWE: (88%), (81%), (64%), (58%), (44%), and (34%). Virulence genes factors among isolates from LCWE were: (78%), (67%), (44%), and (44%). Two different genes ( and ) were identified in all confirmed isolates. Among , (50%) and (67%) were detected. In , (56%) and (100%) were also identified. This finding reveals that the studied aquatic niches pose serious potential health risk with species harbouring virulence signatures. The distribution of virulence genes is valuable for ecological site quality, as well as epidemiological marker in the control and management of diseases caused by species. Regular monitoring of HWW and communal wastewater effluent would allow relevant establishments to forecast, detect, and mitigate any public health threats in advance.
PubMed: 37894107
DOI: 10.3390/microorganisms11102449 -
International Journal of Biological... Dec 2023A number of carboligases, which catalyze condensation of C1- and/or C2-aldehydes into multi-carbon products, have been reported. However, their catalytic activities...
A number of carboligases, which catalyze condensation of C1- and/or C2-aldehydes into multi-carbon products, have been reported. However, their catalytic activities and/or regioselectivities remained rather low. Thereby, this study has focused on engineering of C1 and C2 carboligases for the regioselective condensation of C1-formaldehyde into C4-erythrulose via C2-glycolaldehyde. The crystal structure of the glyoxylate carboligase from Escherichia coli (EcGCL) was elucidated in complex with glycolaldehyde. A structure-guided rationale generated several mutants, one of whose catalytic activity reached 15.6 M·s, almost 10 times greater than the wild-type enzyme. Another variant (i.e., EcGCL) has shown significantly increased stability to the glycolaldehyde toxicity, enabling production of glycolaldehyde to 31 mM from 75 mM formaldehyde (conversion: 83 %). Besides, the E1 subunit of α-ketoglutarate dehydrogenase complex from Vibrio vulnificus (VvSucA) was engineered as a regiospecific C2 carboligase for condensation of glycolaldehyde into erythrulose. The combination of EcGCL and VvSucA led to the cascade production of erythrulose to 8 mM from 90 mM formaldehyde via glycolaldehyde without byproduct formation. This study will contribute to valorization of C1 gases into industrially relevant multi-carbon products in an environment-friendly way.
Topics: Thiamine Pyrophosphate; Escherichia coli; Formaldehyde; Carbon
PubMed: 37890751
DOI: 10.1016/j.ijbiomac.2023.127674 -
MicrobiologyOpen Oct 2023Rifampicin resistance, which is genetically linked to mutations in the RNA polymerase β-subunit gene rpoB, has a global impact on bacterial transcription and cell...
Rifampicin resistance, which is genetically linked to mutations in the RNA polymerase β-subunit gene rpoB, has a global impact on bacterial transcription and cell physiology. Previously, we identified a substitution of serine 522 in RpoB (i.e., RpoB ) conferring rifampicin resistance to Vibrio vulnificus, a human food-borne and wound-infecting pathogen associated with a high mortality rate. Transcriptional and physiological analysis of V. vulnificus expressing RpoB showed increased basal transcription of stress-related genes and global virulence regulators. Phenotypically these transcriptional changes manifest as disturbed osmo-stress responses and toxin-associated hypervirulence as shown by reduced hypoosmotic-stress resistance and enhanced cytotoxicity of the RpoB strain. These results suggest that RpoB-linked rifampicin resistance has a significant impact on V. vulnificus survival in the environment and during infection.
Topics: Humans; Rifampin; Vibrio vulnificus; Bacterial Proteins; Mutation; Virulence; DNA-Directed RNA Polymerases
PubMed: 37877661
DOI: 10.1002/mbo3.1379 -
Frontiers in Microbiology 2023In the human pathogen , the quorum-sensing (QS) signal molecule cyclo-(L-phenylalanine-L-proline) (cFP) plays a critical role in triggering a signaling pathway involving...
In the human pathogen , the quorum-sensing (QS) signal molecule cyclo-(L-phenylalanine-L-proline) (cFP) plays a critical role in triggering a signaling pathway involving the components LeuO-vHUαβ-RpoS-KatG via the membrane signal receptor ToxR. In this study, we investigated the impact of iron on the expression of these signaling components. We found that the transcription of the membrane sensor protein ToxR was not significantly affected by Fur-iron. However, Fur-iron repressed the transcription of genes encoding all the downstream cytoplasmic components in this pathway by binding to the upstream regions of these genes. Consequently, the expression of genes regulated by the alternative sigma factor RpoS, as well as the resistance to hydrogen peroxide conferred by KatG, were repressed. Additionally, we observed that in , genes dependent on ToxR showed higher expression levels in a -deletion mutant compared to the wild type. These findings indicate that iron, in association with Fur, represses virtually all the cytoplasmic components responsible for the ToxR-dependent cFP-signaling pathways in these two pathogenic species. This study, along with our previous reports demonstrating the repression of components involved in AI-2 dependent QS signaling by Fur-iron, highlights the crucial role of iron in quorum-sensing regulation, which is closely associated with the pathogenicity of this human pathogen.
PubMed: 37860134
DOI: 10.3389/fmicb.2023.1273095