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MSphere Jun 2019The azithromycin resistance conferred by phosphotransferase is encoded in the gene (A). This gene has been discovered in and reported for many bacterial species. We...
The azithromycin resistance conferred by phosphotransferase is encoded in the gene (A). This gene has been discovered in and reported for many bacterial species. We examined the prevalence of azithromycin resistance in (AR-VF) isolated during 2014 to 2015 from the hospitalized acute diarrheal patients in Kolkata, India. Most of the isolates are identified as the sole pathogen (54%). The prevalence of AR-VF was higher in 2015 (19 [68%]) than in 2014 (9 [32%]). Among AR-VF isolates, the azithromycin MICs ranged from 4 to >256 mg/liter. Twenty-eight of the 48 (58%) isolates harbored the gene (A) and phenotypically resistant to azithromycin. All the AR-VF isolates remained susceptible to doxycycline. In addition to azithromycin, other antimicrobial resistance-encoding genes of AR-VF were also characterized. All the AR-VF isolates were positive for class 1 integron, and most of them (17/28) carried the gene cassettes. Only one isolate was positive for the gene, which encodes resistance to erythomycin. The majority of the isolates were resistant to β-lactam antibiotics ( [96%], [93%], and [68%]) and aminoglycoside actetyltransferase, conferring resistance to ciprofloxacin-modifying enzyme [] (96%). Analyses by pulsed-field gel electrophoresis (PFGE) showed that the AR-VF isolates belonged to different genetic lineages. This is the first study to report azithromycin resistance and the presence of the (A) gene in isolates. Circulation of AR-VF isolates with high azithromycin MICs is worrisome, since it may limit the treatment options for diarrheal infections. The progressive rise in antibiotic resistance among enteric pathogens in developing countries is becoming a big concern. India is one of the largest consumers of antibiotics, and their use is not well regulated. is increasingly recognized as an emerging diarrheal pathogen of public health importance. Here we report the emergence of azithromycin resistance in isolates from diarrheal patients in Kolkata, India. Azithromycin has been widely used in the treatment of various infections, both in children and in adults. Resistance to azithromycin is encoded in the gene (A). Emerging azithromycin resistance in is a major public health challenge, and future studies should be focused on identifying ways to prevent the dissemination of this antibiotic resistance gene.
Topics: Anti-Bacterial Agents; Azithromycin; Child; Child, Preschool; Diarrhea; Drug Resistance, Multiple, Bacterial; Female; Humans; India; Male; Microbial Sensitivity Tests; Phosphotransferases; Vibrio
PubMed: 31189560
DOI: 10.1128/mSphere.00215-19 -
Biochemical and Biophysical Research... May 2019Vibrio fluvialis is considered as a human pathogen in developing countries. This bacterium is widely distributed in seawater and harbors that contains traces of salt. V....
Vibrio fluvialis is considered as a human pathogen in developing countries. This bacterium is widely distributed in seawater and harbors that contains traces of salt. V. fluvialis can cause human enteritis and diarrhea, which has broken out at a global scale. Lipopolysaccharide (LPS) is a key bacterial antigen used to classify V. fluvialis serogroups. In this research, phage display technology was adopted to isolate nanobodies from a naïve phage library by using LPS as the target antigen. The isolated nanobody was tested in LPS ELISA and bacterial enzyme-linked immunosorbent assay Nanobody V23 had a high affinity toward the pathogen and was utilized to synthesize immunomagnetic beads for the enrichment of V. fluvialis. The capture efficiency of the immunomagnetic beads against V. fluvialis was 90.7 ± 3.2% (N = 3) through the plate-counting method. We generated a high-affinity nanobody against LPS from V. fluvialis and developed a rapid method of enriching V. fluvialis by using immunomagnetic beads.
Topics: Cell Surface Display Techniques; Enzyme-Linked Immunosorbent Assay; Humans; Immunomagnetic Separation; Lipopolysaccharides; Single-Domain Antibodies; Vibrio; Vibrio Infections
PubMed: 30905409
DOI: 10.1016/j.bbrc.2019.03.104 -
Cureus Jul 2023is a pathogenic Gram-negative bacillus typically resulting in gastroenteritis in humans. It has recently been identified as a growing concern for public health. The...
is a pathogenic Gram-negative bacillus typically resulting in gastroenteritis in humans. It has recently been identified as a growing concern for public health. The case presented is an uncommon case of causing bacteremia, as well as hemorrhagic skin lesions. Other reported cases have also highlighted unexpected manifestations, such as cerebritis, bacterial peritonitis, and otitis externa. These atypical presentations can happen in immunocompromised individuals. There are no established guidelines currently for the treatment of bacteremia. This case presents bacteremia that improved with doxycycline without the need for incision and drainage of the patient's lower extremity lesions.
PubMed: 37521591
DOI: 10.7759/cureus.42612 -
Microbiology Spectrum Feb 2023We found a new gene, , carried by a multidrug resistance plasmid in a clinical Vibrio furnissii isolate. QnrVF1 exhibits 44.6% to 72.5% similarity in identity with...
We found a new gene, , carried by a multidrug resistance plasmid in a clinical Vibrio furnissii isolate. QnrVF1 exhibits 44.6% to 72.5% similarity in identity with other Qnr family proteins. alleles are mainly encoded by chromosomes of V. furnissii and Vibrio fluvialis. Phylogenic analysis showed that QnrVF1 and QnrVF2 form a distinct clade in Qnr proteins. Thus, represents a new family. In addition, the gene is often flanked by the mobile element IS. Thus, it is likely that is mobilized by IS from chromosome to plasmid in V. furnissii. Quinolones are widely used drugs. Bacteria contain a quinolone resistance gene, which mediates resistance to quinolones. Currently, seven families of Qnr proteins, QnrVC, QnrA, QnrB, QnrC, QnrD, QnrE, and QnrS, have been identified. However, it is unclear whether there are any other families. In this study, we identified a new family, . We found many V. furnissii and V. fluvialis strains that possess chromosomal alleles, suggesting that V. furnissii and V. fluvialis are the reservoirs of . We also found that QnrVF1 confers low-level resistance to quinolones. IS may facilitate the spread of . The emergence and spread of may pose a considerable threat to public health.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Quinolones; Plasmids; Microbial Sensitivity Tests
PubMed: 36656040
DOI: 10.1128/spectrum.01934-22 -
International Journal of Infectious... Apr 2024South Asia remains home to foodborne diseases caused by the Vibrio species. We aimed to compile and update information on the epidemiology of vibriosis in South Asia. (Meta-Analysis)
Meta-Analysis
OBJECTIVES
South Asia remains home to foodborne diseases caused by the Vibrio species. We aimed to compile and update information on the epidemiology of vibriosis in South Asia.
METHODS
For this systematic review and meta-analysis, we searched PubMed, Web of Science, EMBASE, and Google Scholar for studies related to vibriosis in South Asia published up to May 2023. A random-effects meta-analysis was used to estimate the pooled isolation rate of non-cholera-causing Vibrio species.
RESULTS
In total, 38 studies were included. Seven of these were case reports and 22 were included in the meta-analysis. The reported vibriosis cases were caused by non-O1/non-O139 V. cholerae, V. parahaemolyticus, V. fluvialis, and V. vulnificus. The overall pooled isolation rate was 4.0% (95% confidence interval [CI] 3.0-5.0%) in patients with diarrhea. Heterogeneity was high (I = 98.0%). The isolation rate of non-O1/non-O139 V. cholerae, V. parahaemolyticus, and V. fluvialis were 9.0 (95% CI 7.0-10.0%), 1.0 (95% CI 1.0-2.0%), and 2.0 (95% CI: 1.0-3.0%), respectively. Regarding V. parahaemolyticus, O3:K6 was the most frequently isolated serotype. Cases peaked during summer. Several studies reported antibiotic-resistant strains and those harboring extended-spectrum beta-lactamases genes.
CONCLUSIONS
This study demonstrates a high burden of infections caused by non-cholera-causing Vibrio species in South Asia.
Topics: Humans; Vibrio cholerae; Vibrio Infections; Foodborne Diseases; Diarrhea; Asia, Southern
PubMed: 38311027
DOI: 10.1016/j.ijid.2024.01.022 -
International Journal of Molecular... May 2024is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and...
is an emerging foodborne pathogenic bacterium that can cause severe cholera-like diarrhea and various extraintestinal infections, posing challenges to public health and food safety worldwide. The arginine deiminase (ADI) pathway plays an important role in bacterial environmental adaptation and pathogenicity. However, the biological functions and regulatory mechanisms of the pathway in remain unclear. In this study, we demonstrate that L-arginine upregulates the expression of the ADI gene cluster and promotes the growth of . The ADI gene cluster, which we proved to be comprised of two operons, and , significantly enhances the survival of in acidic environments both in vitro (in culture medium and in macrophage) and in vivo (in mice). The mRNA level and reporter gene fusion analyses revealed that ArgR, a transcriptional factor, is necessary for the activation of both and transcriptions. Bioinformatic analysis predicted the existence of multiple potential ArgR binding sites at the and promoter regions that were further confirmed by electrophoretic mobility shift assay, DNase I footprinting, or point mutation analyses. Together, our study provides insights into the important role of the ArgR-ADI pathway in the survival of under acidic conditions and the detailed molecular mechanism. These findings will deepen our understanding of how environmental changes and gene expression interact to facilitate bacterial adaptations and virulence.
Topics: Animals; Gene Expression Regulation, Bacterial; Bacterial Proteins; Mice; Hydrolases; Promoter Regions, Genetic; Operon; Repressor Proteins; Vibrio; Arginine; Multigene Family; Virulence; Microbial Viability
PubMed: 38891866
DOI: 10.3390/ijms25115679 -
Veterinary World Jun 2020bacteria are autochthonous inhabitants of aquatic and marine environments. Certain strains are responsible for important seafood-borne outbreaks in developed nations....
BACKGROUND AND AIM
bacteria are autochthonous inhabitants of aquatic and marine environments. Certain strains are responsible for important seafood-borne outbreaks in developed nations. The aim of this study was to investigate the occurrence of spp. along the Algerian Mediterranean coast in several samples of two prominent wild and farmed marine fishes, and .
MATERIALS AND METHODS
A total of 350 (n=280 farmed and n=70 wild) and 340 (n=250 farmed and n=90 wild) were sampled among three different locations along the Algerian Mediterranean coastal area. The samples were processed for research according to the ISO methods. Isolated colonies were identified utilizing biochemical tests and consecutively confirmed with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, combined with polymerase chain reaction (PCR) analysis when appropriate, or confirmed with PCR analysis alone.
RESULTS
A total of 42 spp. were detected only among the farmed fishes. Taking into account, all 690 fishes sampled, the incidence of spp. was 6.08% (with peaks up to 7.92%) among the total number of farmed fishes. Overall, 25 strains were isolated from and 17 strains were isolated from . The isolated strains belonged to four different species and were represented as follows: (n=20), (n=15), (n=5), and (n=2). The incidence of was higher in places characterized by greater levels of anthropogenic contamination of seawater.
CONCLUSION
Considering the growing production and consequent rising consumption of farmed fish in Algeria, the reported incidence of and the presence of potentially pathogenic strains of such as cause particular concern for food safety matters. Even if innovative and natural techniques are desired in aquaculture, proper hygiene and manufacturing practices are essential for the correct management of infection risk in farmed fishes at both industrial and domestic levels.
PubMed: 32801574
DOI: 10.14202/vetworld.2020.1199-1208 -
Emerging Microbes & Infections Dec 2021is an emerging enteric pathogen of increasing public health threat. Two quorum sensing (QS) systems, VfqI-VfqR and CqsA/LuxS-HapR, and two type VI secretion systems...
is an emerging enteric pathogen of increasing public health threat. Two quorum sensing (QS) systems, VfqI-VfqR and CqsA/LuxS-HapR, and two type VI secretion systems (T6SSs), VflT6SS1 and VflT6SS2, have been identified in . Whether there exists any correlation between the two systems is unclear. In this study, we found that CqsA/LuxS-HapR circuit regulator LuxO represses while HapR activates VflT6SS2. The effect of LuxO is more pronounced at low cell density and is HapR-dependent. Deletion of abolished Hcp expression and alleviated antibacterial virulence. However, these effects were rescued by HapR-expressing plasmid. Reporter fusion analyses showed that HapR is required for the promoter activities of VflT6SS2. Sequence inspection of the major cluster promoter revealed two potential Motif 1 HapR binding sites, and their bindings to HapR were confirmed by both electrophoretic mobility shift assay (EMSA) and DNase I footprinting assay. Meanwhile, two single Motif 2 sites were identified in 2_a (A) and 2_b (B) promoter regions of the orphan cluster which are less conserved and displayed lower affinities to HapR. Together, our study demonstrated that CqsA/LuxS-HapR QS manipulate VflT6SS2 in , and this finding will enhance our understanding of possible crosstalk between T6SS and QS in microbes.
Topics: Amino Acid Motifs; Bacterial Proteins; Binding Sites; DNA-Binding Proteins; Gene Expression Regulation, Bacterial; Genetic Complementation Test; Mutation; Promoter Regions, Genetic; Quorum Sensing; RNA, Bacterial; Repressor Proteins; Trans-Activators; Type VI Secretion Systems; Vibrio; Virulence
PubMed: 33689580
DOI: 10.1080/22221751.2021.1902244 -
Indian Journal of Microbiology Mar 2018In an earlier study from this laboratory, BD146, a clinical isolate from Kolkata, India, 2002, was found to be resistant to all the fourteen antibiotics tested. It...
A Highly Promiscuous Integron, Plasmids, Extended Spectrum Beta Lactamases and Efflux Pumps as Factors Governing Multidrug Resistance in a Highly Drug Resistant Isolate BD146 from Kolkata, India.
In an earlier study from this laboratory, BD146, a clinical isolate from Kolkata, India, 2002, was found to be resistant to all the fourteen antibiotics tested. It harboured a high copy number plasmid pBD146 and a low copy number plasmid. In the present study, a more detailed analysis was carried out to unravel different resistance mechanisms in this isolate. Sequencing showed that variable region of class 1 integron located on low copy number plasmid harbored 3-A--A1 gene cassettes. Analysis for extended spectrum beta lactamases (ESBLs) revealed that BD146 was ESBL positive. Efflux pumps were involved in the drug resistance phenotype for chloramphenicol, kanamycin, streptomycin and tetracycline. Sequence analysis of pBD146 revealed the presence of genes encoding an integrase with a unique sequence having little similarity to other known integrases, toxin-antitoxin (), a replicase, trimethoprim resistance () and quinolone resistance (). Presence of A, putative novel integrase and toxin-antitoxin system in has been documented for the first time in this report. pBD146 showed 99% sequence similarity with pVN84 from O1 of Vietnam, 2004 and a plasmid from v110 of Hong Kong, 2010. Conjugation experiments proved the ability of pBD146 and the low copy number plasmid, to get transferred to another host imparting their antibiotic resistance traits to the transconjugants. Therefore, present study has indicated that plasmids played an important role for dissemination of drug resistance.
PubMed: 29434398
DOI: 10.1007/s12088-017-0687-8 -
Probiotics and Antimicrobial Proteins Aug 2021Anti-lipopolysaccharide factors (ALFs) are antimicrobial peptides of approximately 100 amino acid residues with a broad spectrum of antimicrobial activity. It is an...
Anti-lipopolysaccharide factors (ALFs) are antimicrobial peptides of approximately 100 amino acid residues with a broad spectrum of antimicrobial activity. It is an amphipathic peptide with an N-terminal hydrophobic region and a lipopolysaccharide binding domain (LBD). In the present study, we report an isoform of the anti-lipopolysaccharide factor (Mm-ALF) from the speckled shrimp, Metapenaeus monoceros. A 359 bp cDNA encoded 119 amino acids, and the sequence showed 99.16% similarity to ALF from the shrimp Fenneropenaeus indicus. The mature peptide of 94 amino acids has a net charge of +8, molecular weight 10.62 kDa, and pI 10.11. The mature peptide Mm-ALF was recombinantly expressed in E. coli Rosetta-gami cells, and the peptide was isolated and purified. The rMm-ALF exhibited notable antibacterial activity against Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram-negative (Escherichia coli, Edwardsiella tarda, Aeromonas hydrophila, Pseudomonas aeruginosa, Vibrio parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Vibrio proteolyticus, Vibrio cholerae and Vibrio fluvialis) bacteria.
Topics: Amino Acids; Animals; Antimicrobial Peptides; Gram-Negative Bacteria; Gram-Positive Bacteria; Lipopolysaccharides; Penaeidae
PubMed: 33569748
DOI: 10.1007/s12602-021-09741-3