scholarly journals ANTIBIOFILM FORMATION ACTIVITY, RESISTANT GENES PROFILING AND DETECTION OF VIRULENCE FACTORS OF TOXIGENIC Vibrio cholerae ISOLATES FROM KISUMU COUNTY, KENYA

2021 ◽  
Author(s):  
Silas O. Awuor ◽  
Omwenga O. Eric ◽  
Ibrahim I. Daud
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Tetracycline Resistance ◽  
Positive Control ◽  
Toxin Gene ◽  
Pcr Assay ◽  
Tetracycline Resistance Gene ◽  
Resistant Genes ◽  
Standard Procedures ◽  
El Tor

ABSTRACTIntroductionVibrio cholerae can switch between motile and biofilm lifestyles with some of its strains forming biofilms in addition to production of various virulence traits and possessing antimicrobial resistance traits. This study is aim to show antibiofilm formation activity, resistant genes profiling and detection of virulence factors of toxigenic vibrio cholerae isolates from Kisumu County.MethodologyA total of 119 Vibrio cholerae O1, biotype El Tor isolates collected during 2017 cholera outbreak in Kisumu County were used for this study. The samples were cultured on TCBS and PCR assay carried out using standard procedures. Biofilm assay tests and detection of virulence factors were also done by use of standard procedures.ResultsOf the 101 confirmed vibrio cholerae isolates, 80.2% possessed the cholera toxin gene (ctxA) whereas 19.8% did not. Analysis of the toxR gene revealed that 98.0% harbored the toxR gene and only 2.0% did not. It was also revealed that 80.2% harbored the class I integron (inDS gene) while 19.8% did not, 93.1% were confirmed to possess the SXT integrating conjugative element (ICE) while 7.0% did not. The tetracycline resistance gene was present in 96.0% of the isolates. In 7 isolants strains which were resistance to common used antibiotics were screened for biofilm formation. Three of the strains (04/17-07, 06/17-14, and 05/17-03) failed to form biofilm while four strains namely 03/17-16, 02/17-09, 04/17-13 and P. aeruginosa ATCC 10145 as a positive control formed biofilms. In addition, out of those 7 isolants 71.42% produced protease, 85.71% produced phospholipases, 71.42% of isolates has the ability to produce lipase and 100% were able to produce the haemolysin.ConclusionAn understanding of this intricate signaling pathway is essential for the development of methods to treat and prevent this devastating disease.

scholarly journals Influence of Some Physicochemical Stresses on the Survival of Vibrio cholerae O1 at Non-Culturable State

1970 ◽  
Vol 24 (2) ◽  
pp. 133-136 ◽  
Author(s):  
M Mahfuzul Haque ◽  
Sirajul Islam Khan ◽  
Chowdhury Rafiqul Ahsan
Keyword(s):  
Polymerase Chain Reaction ◽  
Vibrio Cholerae ◽  
Toxin Gene ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Nonculturable State ◽  
Vibrio Cholerae O1 ◽  
Polymerase Chain ◽  
Specific Fragment ◽  
El Tor

Survival study of toxigenic Vibrio cholerae O1 Classical Inaba and El Tor Ogawa biotypes was carried out in artificial microcosm without any nutrients under stressed physiochemical conditions. The organisms were found to undergo viable but non-culturable (VBNC) state, which was detected by polymerase chain reaction (PCR) technique using primers that flank a specific fragment of the cholera toxin gene (ctx). The findings of the study showed that about 89% of samples gave positive result although the organisms were in nonculturable state. Depending upon the conditions the Classical biotype of vibrios had undergone non-culturable state within 2-15 days and 55-92 days were subjected to PCR assay after 45 and 120 days of incubation respectively. A similar tend was also observed in case of El Tor biotype. With non-culturable cell only 5 of 18 microcosms (of both Classical and El Tor biotypes) at pH 4.5 showed no viability. Since the PCR assay demonstrated positive results after 90 (in case of El Tor biotype) and 120 days (in case of Classical biotype), the total survival time thus ranges over 3 and 4 months. Thus PCR has an important advantage over the techniques those are used in routine laboratories for the identification of pathogenic organisms. Keywords: Physicochemical stresses, Survivality, Vibrio cholerae, Artificial microcosms, Polymerase chain reaction (PCR), Non-culturable state, Viable but non-culturable (VBNC)DOI: http://dx.doi.org/10.3329/bjm.v24i2.1258 Bangladesh J Microbiol, Volume 24, Number 2, December 2007, pp 133-136

scholarly journals Examination of Diverse Toxin-Coregulated Pilus-Positive Vibrio cholerae Strains Fails To Demonstrate Evidence for Vibrio Pathogenicity Island Phage

2003 ◽  
Vol 71 (6) ◽  
pp. 2993-2999 ◽  
Author(s):  
Shah M. Faruque ◽  
Jun Zhu ◽  
Asadulghani ◽  
M. Kamruzzaman ◽  
John J. Mekalanos
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Genetic Variants ◽  
Horizontal Transfer ◽  
Pathogenicity Island ◽  
Culture Conditions ◽  
Filamentous Phage ◽  
Colonization Factor ◽  
Toxin Coregulated Pilus ◽  
El Tor

ABSTRACT The major virulence factors of toxigenic Vibrio cholerae are cholera toxin, which is encoded by a lysogenic filamentous bacteriophage (CTXΦ), and toxin-coregulated pilus (TCP), an essential colonization factor that is also the receptor for CTXΦ. The genes involved in the biosynthesis of TCP reside in a pathogenicity island, which has been reported to correspond to the genome of another filamentous phage (designated VPIΦ) and to encode functions necessary for the production of infectious VPIΦ particles. We examined 46 V. cholerae strains having diverse origins and carrying different genetic variants of the TCP island for the production of the VPIΦ and CTXΦ in different culture conditions, including induction of prophages with mitomycin C and UV irradiation. Although 9 of 10 V. cholerae O139 strains and 12 of 15 toxigenic El Tor strains tested produced extracellular CTXΦ, none of the 46 TCP-positive strains produced detectable VPIΦ in repeated assays, which detected as few as 10 particles of a control CTX phage per ml. These results contradict the previous report regarding VPIΦ-mediated horizontal transfer of the TCP genes and suggest that the TCP island is unable to support the production of phage particles. Further studies are necessary to understand the mechanism of horizontal transfer of the TCP island.

scholarly journals Non-O1/Non-O139 Vibrio cholerae Carrying Multiple Virulence Factors and V. cholerae O1 in the Chesapeake Bay, Maryland

2015 ◽  
Vol 81 (6) ◽  
pp. 1909-1918 ◽  
Author(s):  
Daniela Ceccarelli ◽  
Arlene Chen ◽  
Nur A. Hasan ◽  
Shah M. Rashed ◽  
Anwar Huq ◽  
...  
Keyword(s):  
Chesapeake Bay ◽  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Fluorescent Antibody ◽  
Secretion System ◽  
Surveillance Program ◽  
Toxin Gene ◽  
Protease Gene ◽  
Content Type ◽  
Pathogenic Variants

ABSTRACTNon-O1/non-O139Vibrio choleraeinhabits estuarine and coastal waters globally, but its clinical significance has not been sufficiently investigated, despite the fact that it has been associated with septicemia and gastroenteritis. The emergence of virulent non-O1/non-O139V. choleraeis consistent with the recognition of new pathogenic variants worldwide. Oyster, sediment, and water samples were collected during a vibrio surveillance program carried out from 2009 to 2012 in the Chesapeake Bay, Maryland.V. choleraeO1 was detected by a direct fluorescent-antibody (DFA) assay but was not successfully cultured, whereas 395 isolates of non-O1/non-O139V. choleraewere confirmed by multiplex PCR and serology. Only a few of the non-O1/non-O139V. choleraeisolates were resistant to ampicillin and/or penicillin. Most of the isolates were sensitive to all antibiotics tested, and 77 to 90% carried the El Tor variant hemolysin genehlyAET, the actin cross-linking repeats in toxin genertxA, the hemagglutinin protease genehap, and the type 6 secretion system. About 19 to 21% of the isolates carried the neuraminidase-encoding genenanHand/or the heat-stable toxin (NAG-ST), and only 5% contained a type 3 secretion system. None of the non-O1/non-O139V. choleraeisolates containedVibriopathogenicity island-associated genes. However,ctxA,ace, orzotwas present in nine isolates. Fifty-five different genotypes showed up to 12 virulence factors, independent of the source of isolation, and represent the first report of both antibiotic susceptibility and virulence associated with non-O1/non-O139V. choleraefrom the Chesapeake Bay. Since these results confirm the presence of potentially pathogenic non-O1/non-O139V. cholerae, monitoring for totalV. cholerae, regardless of serotype, should be done within the context of public health.

scholarly journals Haitian-like genetic traits with creeping MIC of Azithromycin in Vibrio cholerae O1 isolates from Puducherry, India

2020 ◽  
Vol 69 (3) ◽  
pp. 372-378
Author(s):  
Regina Sumitha Mohanraj ◽  
Prosenjit Samanta ◽  
Asish K. Mukhopadhyay ◽  
Jharna Mandal
Keyword(s):  
Vibrio Cholerae ◽  
Postgraduate Medical Education ◽  
Tetracycline Resistance ◽  
Progressive Increase ◽  
Test Method ◽  
Genetic Traits ◽  
Content Type ◽  
Antimicrobial Resistance Genes ◽  
Jawaharlal Institute ◽  
El Tor

Introduction. The emergence of novel strains of Vibrio cholerae O1 El Tor biotype has gained attention due to causing several epidemics around the world. Variant strains have evolved as a result of the acquisition of genes that confer extended virulence and pathogenicity. Aim. This study aimed to determine the presence of the most recently emerging Haitian-like genetic traits among the isolates from Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, Southern India. We also wanted to detect the prevalence of the sulfamethoxazole and trimethoprim (SXT) element, which is an integrating conjugative element (ICE) and the antimicrobial resistance genes present in our isolates. Methodology. Identification of Haitian-specific alleles was done by mismatched amplification mutation assay PCR (MAMA-PCR). The presence of SXT elements was carried out by PCR by detecting int, eex, att-prfC and setR genes. Detection of antibiotic resistance determinant, sul(1,2,3); dfr(A1,18,5) for trimethoprim resistance, tet(A,B,C,D,E,Y,G,M), tet34 for tetracycline resistance and erm(A,B,C), mph(A,B), ere(A,B), msr(A,D) for azithromycin resistance were targeted by PCR. The MIC of tetracycline, ciprofloxacin and azithromycin was determined by the E-test method. Results. Of the 95 isolates, 60 % of the isolates were found to carry Haitian-specific alleles of ctxB, tcpA and rtxA gene, 100 % of the isolates were found to carry SXT elements. All the isolates harboured the four conserved genes of the SXT element, except one which had only eex, att-prfC, setR genes. About 99 % harboured sul2 and dfrA1 genes. No tet and macrolide genes were detected. We observed a progressive increase in the MIC of azithromycin ranging from 0.75 µg ml−1 to 2 µg ml−1. Conclusion. None of the isolates were the prototype El Tor biotype. All the isolates were a Haitian variant. The presence of SXT elements across all our isolates and their creeping MIC of azithromycin is a matter of concern. Further testing for other genetic determinants of resistance will be carried out in our future studies.

scholarly journals Quantitative Assessment of the Tetracycline Resistance Gene Pool in Cheese Samples by Real-Time TaqMan PCR

2007 ◽  
Vol 73 (5) ◽  
pp. 1676-1677 ◽  
Author(s):  
Michele Y. Manuzon ◽  
Scott E. Hanna ◽  
Hongliang Luo ◽  
Zhongtang Yu ◽  
W. James Harper ◽  
...  
Keyword(s):  
Real Time ◽  
Gene Pool ◽  
Antibiotic Resistance Genes ◽  
Tetracycline Resistance ◽  
Food Samples ◽  
Independent Method ◽  
Pcr Assay ◽  
Tetracycline Resistance Gene ◽  
Culture Independent ◽  
Taqman Pcr

ABSTRACT A TaqMan real-time PCR assay was developed to quantify the tetS gene pool present in retail cheeses. This protocol offers a rapid, specific, sensitive, and culture-independent method for assessing antibiotic resistance genes in food samples rich in fats and proteins.

scholarly journals Expression of virulence factors by classical and El Tor Vibrio cholerae in vivo and in vitro

1990 ◽  
Vol 7 (2-3) ◽  
pp. 221-228 ◽  
Author(s):  
Gunhild Jonson ◽  
Ann-Man Svennerholm ◽  
Jan Holmgren
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
El Tor

scholarly journals Virulence factors in environmental and clinical Vibrio cholerae from endemic areas in Kenya

2014 ◽  
Vol 3 (1) ◽  
Author(s):  
Racheal W. Kimani ◽  
Anne W. T. Muigai ◽  
Willie Sang ◽  
John N. Kiiru ◽  
Samuel Kariuki
Keyword(s):  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Environmental Samples ◽  
Virulence Genes ◽  
Clinical Strains ◽  
Seasonal Epidemics ◽  
Polymerase Chain ◽  
Endemic Areas ◽  
Study Sites ◽  
El Tor

Background: Since 1971, Kenya has had repeated cholera outbreaks. However, the cause of seasonal epidemics of cholera is not fully understood and neither are the factors that drive epidemics, both in Kenya and globally.Objectives: The objectives of the study were to determine the environmental reservoirs of V. cholerae during an interepidemic period in Kenya and to characterise their virulence factors.Methods: One hundred (50 clinical, 50 environmental) samples were tested for V. cholerae isolates using both simplex and multiplex polymerase chain reaction.Results: Both sediments and algae from fishing and landing bays yielded isolates of V. cholerae. Clinical strains were characterised along with the environmental strains for comparison. All clinical strains harboured ctxA, tcpA (El Tor), ompU, zot, ace, toxR, hylA (El Tor) and tcpI genes. Prevalence for virulence genes in environmental strains was hylA (El Tor) (10%), toxR (24%), zot (22%), ctxA (12%),tcpI (8%), hylA (26%) and tcpA (12%).Conclusion: The study sites, including landing bays and beaches, contained environmental V. cholerae, suggesting that these may be reservoirs for frequent epidemics. Improved hygiene and fish-handling techniques will be important in reducing the persistence of reservoirs.

scholarly journals The Cyclic Dipeptide Cyclo(Phe-Pro) Inhibits Cholera Toxin and Toxin-Coregulated Pilus Production in O1 El Tor Vibrio cholerae

2010 ◽  
Vol 192 (14) ◽  
pp. 3829-3832 ◽  
Author(s):  
Xiaowen R. Bina ◽  
James E. Bina
Keyword(s):  
Cholera Toxin ◽  
Vibrio Cholerae ◽  
Virulence Factors ◽  
Virulence Gene ◽  
Cyclic Dipeptide ◽  
Present Evidence ◽  
Toxin Coregulated Pilus ◽  
El Tor ◽  
Virulence Regulator

ABSTRACT Cyclo(Phe-Pro) is a cyclic dipeptide produced by multiple Vibrio species. In this work, we present evidence that cyclo(Phe-Pro) inhibits the production of the virulence factors cholera toxin (CT) and toxin-coregulated pilus (TCP) in O1 El Tor Vibrio cholerae strain N16961 during growth under virulence gene-inducing conditions. The cyclo(Phe-Pro) inhibition of CT and TCP production correlated with reduced transcription of the virulence regulator tcpPH and was alleviated by overexpression of tcpPH.

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