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Immunology Apr 2024Induction of antibodies (Abs) against the conformational CD4-induced (CD4i) epitope is frequent in HIV-1 infection. However, the mechanism of development of anti-CD4i...
Induction of antibodies (Abs) against the conformational CD4-induced (CD4i) epitope is frequent in HIV-1 infection. However, the mechanism of development of anti-CD4i Abs is unclear. We used anti-idiotypic (aID) monoclonal Abs (mAbs) of anti-CD4i mAbs to isolate anti-CD4i mAbs from infected subjects and track the causative antigens. One anti-aID mAb sorted from infected subjects by aID mAbs had the characteristics of anti-CD4i Abs, including IGHV1-69 usage and ability to bind to HIV-1 Env enhanced by sCD4. Critical amino acid sequences for the binding of six anti-aID mAbs, with shared idiotope to anti-CD4i mAbs, were analysed by phage display. The identified amino acid sequences showed similarity to proteins from human microbiota and infectious agents. Peptides synthesized from Caudoviricetes sp and Vibrio vulnificus based on the identified sequences were reactive to most anti-aID and some anti-CD4i mAbs. These results suggest that anti-CD4i Abs may evolve from B cells primed by microorganisms.
Topics: Humans; Epitopes; HIV-1; HIV Antibodies; CD4 Antigens; HIV Infections; HIV Envelope Protein gp120
PubMed: 38102962
DOI: 10.1111/imm.13742 -
Environmental Research Mar 2024Vibrio spp. naturally occur in warm water with moderate salinity. Infections with non-cholera Vibrio (vibriosis) cause an estimated 80,000 illnesses and 100 fatalities...
BACKGROUND
Vibrio spp. naturally occur in warm water with moderate salinity. Infections with non-cholera Vibrio (vibriosis) cause an estimated 80,000 illnesses and 100 fatalities each year in the United States. Climate associated changes to environmental parameters in aquatic ecosystems are largely promoting Vibrio growth, and increased incidence of vibriosis is being reported globally. However, vibriosis trends in the northeastern U.S. (e.g., Maryland) have not been evaluated since 2008.
METHODS
Vibriosis case data for Maryland (2006-2019; n = 611) were obtained from the COVIS database. Incidence rates were calculated using U.S. Census Bureau population estimates for Maryland. A logistic regression model, including region, age group, race, gender, occupation, and exposure type, was used to estimate the likelihood of hospitalization.
RESULTS
Comparing the 2006-2012 and 2013-2019 periods, there was a 39% (p = 0.01) increase in the average annual incidence rate (per 100,000 population) of vibriosis, with V. vulnificus infections seeing the greatest percentage increase (53%, p = 0.01), followed by V. parahaemolyticus (47%, p = 0.05). The number of hospitalizations increased by 58% (p = 0.01). Since 2010, there were more reported vibriosis cases with a hospital duration ≥10 days. Patients from the upper eastern shore region and those over the age of 65 were more likely (OR = 6.8 and 12.2) to be hospitalized compared to other patients.
CONCLUSIONS
Long-term increases in Vibrio infections, notably V. vulnificus wound infections, are occurring in Maryland. This trend, along with increased rates in hospitalizations and average hospital durations, underscore the need to improve public awareness, water monitoring, post-harvest seafood interventions, and environmental forecasting ability.
Topics: United States; Humans; Maryland; Vibrio parahaemolyticus; Vibrio vulnificus; Incidence; Ecosystem; Vibrio Infections; Water
PubMed: 38101724
DOI: 10.1016/j.envres.2023.117940 -
Microbial Pathogenesis Jan 2024Vibrio vulnificus is a commonly pathogenic bacterium in cultivated eels, but its pathogenicity to American eel (Anguilla rostrata) and the molecular mechanism of host...
Vibrio vulnificus is a commonly pathogenic bacterium in cultivated eels, but its pathogenicity to American eel (Anguilla rostrata) and the molecular mechanism of host anti-V. vulnificus infection remains uncertain. In this study, American eels were infected with different dose of V. vulnificus to determine the LD. Then, bacterial load in the liver and kidney histopathology were assessed post the LD of V. vulnificus infection. Additionally, gene expressions of 18 immune related genes in the liver, spleen and kidney were detected. Furthermore, transcriptome sequencing and enrichment of differentially expressed genes (DEGs) were analyzed in the eel spleens between pre-infection (Con_0), post-36 h (Vv_36), and post-60 h (Vv_60) infection. The results showed that LD of V. vulnificus to American eels was determined to be 5.0 × 10 cfu/g body weight, and the bacterial load peaked at 24 and 12 h post the infection (hpi) in the kidney and liver, respectively. The histopathology was highlighted by necrotic hepatocytes and splenic cells, congestion blood vessels in liver and spleen, atrophied glomeruli and vacuolization of renal tubular epithelial cells. The results of RT-PCR revealed that 18 host immune-related genes showed significantly up or downregulated expression post-infection compare to that of pre-infection. Finally, results of the RNA-seq revealed 16 DEGs play essential role to the immunosuppression in American eels, and the protein-protein interactions shed light on the widespread upregulation GEGs related to metabolism and immune response maintained the host cell homeostasis post the V. vulnificus infection, shedding new light on our understanding of the V. vulnificus pathogenesis towards understudied American eel and the host anti-V. vulnificus infection strategies in gene transcript.
Topics: Animals; Vibrio vulnificus; Anguilla; Virulence; RNA-Seq; Fish Diseases; Vibrio Infections
PubMed: 38097116
DOI: 10.1016/j.micpath.2023.106498 -
PloS One 2023Heterogeneity of ribosomal RNA (rRNA) sequences has recently emerged as a mechanism that can lead to subpopulations of specialized ribosomes. Our previous study showed...
Heterogeneity of ribosomal RNA (rRNA) sequences has recently emerged as a mechanism that can lead to subpopulations of specialized ribosomes. Our previous study showed that ribosomes containing highly divergent rRNAs expressed from the rrnI operon (I-ribosomes) can preferentially translate a subset of mRNAs such as hspA and tpiA in the Vibrio vulnificus CMCP6 strain. Here, we explored the functional conservation of I-ribosomes across Vibrio species. Exogenous expression of the rrnI operon in another V. vulnificus strain, MO6-24/O, and in another Vibrio species, V. fischeri (strain MJ11), decreased heat shock susceptibility by upregulating HspA expression. In addition, we provide direct evidence for the preferential synthesis of HspA by I-ribosomes in the V. vulnificus MO6-24/O strain. Furthermore, exogenous expression of rrnI in V. vulnificus MO6-24/O cells led to higher mortality of infected mice when compared to the wild-type (WT) strain and a strain expressing exogenous rrnG, a redundant rRNA gene in the V. vulnificus CMCP6 strain. Our findings suggest that specialized ribosomes bearing heterogeneous rRNAs play a conserved role in translational regulation among Vibrio species. This study shows the functional importance of rRNA heterogeneity in gene expression control by preferential translation of specific mRNAs, providing another layer of specialized ribosome system.
Topics: Mice; Animals; Vibrio; RNA, Ribosomal; Ribosomes; Vibrio vulnificus; Operon
PubMed: 38051731
DOI: 10.1371/journal.pone.0289072 -
Journal of Microbiology and... Jan 2024Chemical and physical elements affecting the production of bacterial extracellular vesicles (BEVs) of the human pathogen were quantitatively assessed to optimize the...
Chemical and physical elements affecting the production of bacterial extracellular vesicles (BEVs) of the human pathogen were quantitatively assessed to optimize the conditions for the BEV production by using the western blot quantification for an outer membrane porin OmpU and by fluorescent dye FM4-64. When cells were cultured at 37°C in an enriched medium (2 × Luria Bertani; 2 × LB) in the presence of EDTA, they produced about 70% more BEVs. BEVs were purified from the cells cultured in the established optimal conditions by the density gradient ultracentrifugation. The dynamic light scattering measurement of the purified BEVs showed that the diameter of them ranged from approximately 25 nm to 161 nm. We hypothesized that there may be some features in nucleotide sequences specific to RNAs packaged in BEVs compared to those in cellular RNA molecules. We compared the nucleotide sequences and abundance of sRNAs between in the cellular fraction and in BEVs through next-generation sequencing (NGS). While no distinct feature was observed in the nucleotide sequences of sRNAs between two groups, the length of sRNA fragments from BEVs were significantly shorter than those in cytoplasm.
Topics: Humans; Vibrio vulnificus; RNA; Extracellular Vesicles; RNA, Bacterial
PubMed: 38044684
DOI: 10.4014/jmb.2310.10002 -
Mechanism of action of three different glycogen branching enzymes and their effect on bread quality.International Journal of Biological... Jan 2024Bread staling adversely affects the quality of bread, but starch modification by enzymes can counteract this phenomenon. Glycogen branching enzymes (GBEs) used in this...
Bread staling adversely affects the quality of bread, but starch modification by enzymes can counteract this phenomenon. Glycogen branching enzymes (GBEs) used in this study were isolated from Deinococcus geothermalis (DgGBE), Escherichia coli (EcGBE), and Vibrio vulnificus (VvGBE). These enzymes were characterized and applied for starch dough modification to determine their role in improving bread quality. First, the branching patterns, activity on amylose and amylopectin, and thermostability of the GBEs were determined and compared. EcGBE and DgGBE exhibited better thermostable characteristics than VvGBE, and all GBEs exhibited preferential catalysis of amylopectin over amylose but different degrees. VvGBE and DgGBE produced a large number of short branches. Three GBEs degraded the starch granules and generated soluble polysaccharides. Moreover, the maltose was increased in the starch slurry but most significantly in the DgGBE treatment. Degradation of the starch granules by GBEs enhanced the maltose generation of internal amylases. When used in the bread-making process, DgGBE and VvGBE increased the dough and bread volume by 9 % and 17 %, respectively. The crumb firmness and retrogradation of the bread were decreased and delayed significantly more in the DgGBE bread. Consequently, this study can contribute to understanding the detailed roles of GBEs in the baking process.
Topics: Amylopectin; Amylose; 1,4-alpha-Glucan Branching Enzyme; Bread; Maltose; Starch; Glycogen
PubMed: 38040154
DOI: 10.1016/j.ijbiomac.2023.128471 -
Frontiers in Cellular and Infection... 2023To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) in () infection.
OBJECTIVE
To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) in () infection.
METHODS
A retrospective analysis of patients with infection at the Fifth Affiliated Hospital of Sun Yat-Sen University from January 1, 2020 to April 23, 2023 was conducted. 14 enrolled patients were diagnosed by culture or mNGS. The corresponding medical records were reviewed, and the clinical data analyzed included demographics, epidemiology laboratory findings, physical examination, symptoms at presentation, antibiotic and surgical treatment, and outcome.
RESULTS
In this study, 78.6% (11/14) patients had a history of marine trauma (including fish stab, shrimp stab, crab splints and fish hook wounds), 7.1% (1/14) had eaten seafood, and the remaining 14.3% (2/14) had no definite cause. Isolation of from clinical samples including blood, tissue, fester and secreta. 9 cases were positive for culture, 5 cases were detected synchronously by mNGS and got positive for . 85.7% (12/14) cases accepted surgical treatment, with 1 patient suffering finger amputated. 14 enrolled patients received appropriate antibiotic therapy, and all of them had recovered and discharged. 9 strains isolated in this study were sensitive to most beta-lactam antibiotics, aminoglycosides, quinolones, etc.
CONCLUSION
infection is a common water-exposed disease in Zhuhai, which requires identification of a number of pathogens. Of severe infections with unknown pathogen, mNGS can be used simultaneously, and the potential to detect multiple pathogens is of great help in guiding treatment.
Topics: Animals; Humans; Retrospective Studies; Vibrio Infections; Vibrio vulnificus; Anti-Bacterial Agents; High-Throughput Nucleotide Sequencing
PubMed: 38035326
DOI: 10.3389/fcimb.2023.1210919 -
Frontiers in Microbiology 2023is an opportunistic, global pathogen that naturally inhabits sea water and is responsible for most vibriosis-related deaths. We investigated the genetic characteristics...
is an opportunistic, global pathogen that naturally inhabits sea water and is responsible for most vibriosis-related deaths. We investigated the genetic characteristics of isolated from the clinical blood culture specimen of a patient with hepatitis B virus cirrhosis in 2018 (named as VV2018) by whole genome sequencing (WGS). VV2018 belonged to a novel sequencing type 620 (ST620) and comprised two circular chromosomes, containing 4,389 potential coding sequences (CDSs) and 152 RNA genes. The phylogenetic tree of single nucleotide polymorphisms (SNPs) using 26 representative genomes revealed that VV2108 grouped with two other strains isolated from humans. The pan-genome of was constructed using 26 representative genomes to elucidate their genetic diversity, evolutionary characteristics, and virulence and antibiotic resistance profiles. The pan-genome analysis revealed that VV2018 shared a total of 3,016 core genes (≥99% presence), including 115 core virulence factors (VFs) and 5 core antibiotic resistance-related genes, and 309 soft core genes (≥95 and <99% presence) with 25 other strains. The gene might account for the cefazolin resistance, and comparative analysis of the genetic context of revealed that two genes upstream and downstream of were conserved. The glycosylation () like genes were found in VV2018 compared with Pgl-related proteins in that might affect the adherence of the strain in hosts. The comparative analysis of VV2018 would contribute to a better understanding of the virulence and antibiotic resistance profiles of . Meanwhile much work remains to be done to better understand the function of -like genes in .
PubMed: 38029170
DOI: 10.3389/fmicb.2023.1240835 -
Frontiers in Microbiology 2023Rat species , also known as the brown street rat, is the most abundant mammal after humans in urban areas, where they co-exist with humans and domestic animals. The...
Rat species , also known as the brown street rat, is the most abundant mammal after humans in urban areas, where they co-exist with humans and domestic animals. The reservoir role of of zoonotic pathogens in cities among rodent-borne diseases that could endanger the lives of humans and other mammals. Therefore, understanding the normal microbiome of is crucial for understanding and preventing zoonotic pathogen transmission to humans and animals. We investigated the intestinal microbiome of free-living collected from the Ruili, Nujiang, and Lianhe regions of Yunnan, China, using 16S rRNA gene sequence analysis. Proteobacteria, followed by Firmicutes, and Bacteroidetes were abundant in the intestines of ; however, bacterial compositions varied significantly between samples from different locations. Following a similar trend, Gammaproteobacteria, Bacilli, and Clostridia were among the top bacterial classes in most intestinal samples. The situation differed slightly for the Lianhe and Nujiang samples, although Phyla Bacteroidota and Spirochaetota were most prevalent. The Alpha diversity, Chao1, and Simpson indexes revealed microbial richness among the samples. A slight variation was observed among the samples collected from Ruili, Nujiang, and Lianhe. At species levels, several opportunistic and zoonotic bacterial pathogens, including , , , , , , etc., were revealed in the intestines, implying the need for a regular survey to monitor and control rodent populations. In conclusion, we explored diverse microbial communities in intestines captured from different regions. Further, we identified several opportunistic and potential bacterial pathogens, which still need to be tested for their underlying pathogenesis. The findings of our current study should be considered a warning to the health authorities to implement rat control and surveillance strategies globally.
PubMed: 38029126
DOI: 10.3389/fmicb.2023.1283453 -
Archives of Microbiology Nov 2023The marine bacteria of the Vibrionaceae family are significant from the point of view of their role in the marine geochemical cycle, as well as symbionts and... (Review)
Review
The marine bacteria of the Vibrionaceae family are significant from the point of view of their role in the marine geochemical cycle, as well as symbionts and opportunistic pathogens of aquatic animals and humans. The well-known pathogens of this group, Vibrio cholerae, V. parahaemolyticus, and V. vulnificus, are responsible for significant morbidity and mortality associated with a range of infections from gastroenteritis to bacteremia acquired through the consumption of raw or undercooked seafood and exposure to seawater containing these pathogens. Although generally regarded as susceptible to commonly employed antibiotics, the antimicrobial resistance of Vibrio spp. has been on the rise in the last two decades, which has raised concern about future infections by these bacteria becoming increasingly challenging to treat. Diverse mechanisms of antimicrobial resistance have been discovered in pathogenic vibrios, the most important being the membrane efflux pumps, which contribute to antimicrobial resistance and their virulence, environmental fitness, and persistence through biofilm formation and quorum sensing. In this review, we discuss the evolution of antimicrobial resistance in pathogenic vibrios and some of the well-characterized efflux pumps' contributions to the physiology of antimicrobial resistance, host and environment survival, and their pathogenicity.
Topics: Animals; Humans; Anti-Bacterial Agents; Vibrionaceae; Drug Resistance, Bacterial; Vibrio; Vibrio cholerae; Vibrio parahaemolyticus
PubMed: 38017151
DOI: 10.1007/s00203-023-03731-5