Biochemical studies on the production of neuraminidase by environmental isolates of Vibrio cholerae non-O1 from Bulgaria

2011 ◽  
Vol 57 (7) ◽  
pp. 606-610 ◽  
Author(s):  
Rumyana Eneva ◽  
Stephan Engibarov ◽  
Tanya Strateva ◽  
Radoslav Abrashev ◽  
Ignat Abrashev
Keyword(s):  
Vibrio Cholerae ◽  
Pathogenic Bacteria ◽  
Environmental Isolates ◽  
Anaerobic Conditions ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Cholera Vibrio ◽  
Key Factor ◽  
Aeration Conditions ◽  
The One

Neuraminidase is a key factor in the infectious process of many viruses and pathogenic bacteria. The neuraminidase enzyme secreted by the etiological agent of cholera — Vibrio cholerae О1 — is well studied in contrast with the one produced by non-O1/non-O139 V. cholerae. Environmental non-O1/non-O139 V. cholerae isolates from Bulgaria were screened for production of neuraminidase. The presence of the neuraminidase gene nanH was detected in 18.5% of the strains. Тhe strain showing highest activity (30 U/mL), V. cholerae non-O1/13, was used to investigate the enzyme production in several media and at different aeration conditions. The highest production of extracellular neuraminidase was observed under microaerophilic conditions, which is possibly related to its role in the infection of intestine epithelium, where the oxygen content is low. On the other hand, this is another advantage of the microbe in such microaerophilic environments as sediments and lake mud. The highest production of intracellular neuraminidase was observed at anaerobic conditions. The ratio of extracellular to intracellular neuraminidase production in V. cholerae was investigated. The temperature optimum of the enzyme was determined to be 50 °C and the pH optimum to be 5.6–5.8.

scholarly journals MLVA-TYPING OF CLINICAL STAMPS OF GENETICALLY CHANGED VIBRIO CHOLERAE BIOTYPE EL TOR INSULATED IN RUSSIA AND UKRAINE IN THE PERIOD OF SEVENTH PANDEMIC CHOLERA

2018 ◽  
pp. 37-43
Author(s):  
I. V. Savelieva ◽  
A. N. Kulichenko ◽  
V. N. Saveliev ◽  
D. A. Kovalev ◽  
O. V. Vasilieva ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Vibrio Cholerae ◽  
Genetically Modified ◽  
Cholera Vibrio ◽  
Separate Branch ◽  
Comparative Aspect ◽  
The Russian Federation ◽  
Time Periods ◽  
El Tor ◽  
Mlva Typing

Aim. Conduct in a comparative aspect MLVA-typing of genetically altered cholera vibrio biovar El Tor, isolated from patients during the epidemic (1994) and outbreaks (1993, 1998) in Dagestan with isolates in Mariupol (Ukraine) in 1994-2011 in Moscow (2010, 2012), India (1964, 2006, 2007), Bangladesh 1991, 1994, 2001, 2004) and to establish Phylogenetic connections between strains of cholera vibrios isolated in different years in these territories, to ascertain the source of their drift. Materials and methods. MLVA-tyP-ing was carried out in PCR at 5 variable loci of 35 clinical strains of genetically modified Vibrio cholerae byotyPe El Tor. The obtained amPlicon was studied in the system of automatic caPillary electroPhoresis ExPerion («Bio Rad Laboratories», USA). For Phylogenetic analysis, along with MLVA-genotyPes, 35 strains of Vibrio cholerae from the Institute's collection used Published genotyPes of strains isolated in India, Bangladesh, Haiti. Results. The investigated strains of cholera vibrio are referred to 21 MLVA-tyPes, divided into 2 main clades and 1 seParate branch with clonal clusters and subclusters, each of which contains closely related strains of cholera vibrio genovariants having a different degree of Phylogenetic relationshiP - full or Partial identity of allelic Profiles of five variable loci. The sources of drift of genetically modified Vibrio cholerae byotyPe El Tor to Russia and Ukraine from disadvantaged cholera of India, Bangladesh, Azerbaijan and the countries of the Middle East have been established. Conclusion. The obtained data testify to the PolymorPhism of MLVA-tyPes of genetically altered strains of cholera vibrio of the biologist El Tor, evolved in different years and caused ePidemics or outbreaks of cholera in different territories during different time Periods of the course of the seventh cholera Pandemic, and also suggest the Polyclonal origin of the Vibrio cholerae biovar El Tor and the source of their drift to the territory of the Russian Federation and Ukraine.

scholarly journals Bismuth sulphite media for the isolation of V. cholerae

1940 ◽  
Vol 40 (5) ◽  
pp. 532-537 ◽  
Author(s):  
W. James Wilson ◽  
L. V. Reilly
Keyword(s):  
Vibrio Cholerae ◽  
Solid Medium ◽  
Agar Medium ◽  
Phenol Red ◽  
Cholera Vibrio ◽  
Enrichment Medium ◽  
The Media ◽  
El Tor

1. A fluid enrichment medium containing sulphite and bismuth based on Read's modification of one of Wilson & Blair's media has been devised and the claims of Read (1939) and Seal (1939) as to the value of such a medium has been confirmed.2. A saccharose mannitol sulphite bismuth alcohol phenol red agar medium is described and has been found to allow rich growth of the true cholera vibrio and to inhibit the growth not only of B. coli and B. lactis aërogenes but of many vibrios liable to be mistaken for the true vibrio cholerae.3. Thirty-one strains of true cholera vibrios, obtained from the National Collection, grew rapidly and profusely in the media.4. Of twenty-five cholera-like and para-cholera strains six grew well, whilst the growth of nineteen was scanty or nil.5. Of eleven El Tor vibrios five grew in both fluid and solid bismuth media, five grew only on the solid medium and in one no growth occurred in either medium. The El Tor colonies were much smaller than those of the epidemic cholera strains.

scholarly journals SURVIVAL, INDUCTION AND RESUSCITATION OF Vibrio cholerae FROM THE VIABLE BUT NON-CULTURABLE STATE IN THE SOUTHERN CARIBBEAN SEA

2015 ◽  
Vol 57 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Milagro Fernández-Delgado ◽  
María Alexandra García-Amado ◽  
Monica Contreras ◽  
Renzo Nino Incani ◽  
Humberto Chirinos ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Bacterial Population ◽  
Morphological Changes ◽  
Caribbean Sea ◽  
Vbnc State ◽  
Cholera Vibrio ◽  
Viable Cells ◽  
Southern Caribbean ◽  
Favorable Conditions

The causative agent of cholera, Vibrio cholerae, can enter into a viable but non-culturable (VBNC) state in response to unfavorable conditions. The aim of this study was to evaluate the in situ survival of V. cholerae in an aquatic environment of the Southern Caribbean Sea, and its induction and resuscitation from the VBNC state. V. cholerae non-O1, non-O139 was inoculated into diffusion chambers placed at the Cuare Wildlife Refuge, Venezuela, and monitored for plate, total and viable cells counts. At 119 days of exposure to the environment, the colony count was < 10 CFU/mL and a portion of the bacterial population entered the VBNC state. Additionally, the viability decreased two orders of magnitude and morphological changes occurred from rod to coccoid cells. Among the aquatic environmental variables, the salinity had negative correlation with the colony counts in the dry season. Resuscitation studies showed significant recovery of cell cultivability with spent media addition (p < 0.05). These results suggest that V. cholerae can persist in the VBNC state in this Caribbean environment and revert to a cultivable form under favorable conditions. The VBNC state might represent a critical step in cholera transmission in susceptible areas.

scholarly journals Concerning imported cases of cholera in the city of Almaty, Kazakhstan, 2017

2018 ◽  
pp. 83-87 ◽  
Author(s):  
Z. A. Sagiev ◽  
R. S. Musagalieva ◽  
A. A. Abdirasilova ◽  
T. Z. Ayazbaev ◽  
M. M. Kul’baeva ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Genetic ◽  
Laboratory Diagnosis ◽  
Genetic Studies ◽  
Cholera Vibrio ◽  
Group I ◽  
Highly Sensitive ◽  
Imported Cases ◽  
Methodological Guidelines ◽  
The City

In 2017, from October 15 to November 21, 5 cholera cases imported from India – 3 patients and 2 carriers of V. cholerae – were recorded in Almaty. The patients recovered from the disease. Objective of the study was to characterize the imported cases of cholera and investigate the properties of cholera vibrio strains isolated from patients and carriers of V. cholerae. Materials and methods. Revised were the medical records; blood sera, feces from patients and contact persons were assayed. Studied were sensitivity spectrum to antibacterial preparations of isolated V. cholerae strains according to the “Methodological guidelines on laboratory diagnosis of cholera”, dated September 27, 2010; No 252. Epidemiological, microbiological, immunological and molecular-genetic methods were applied for investigation. Results and conclusions. Consequently to molecular genetic studies, genes of specificity, wbeN and toxicity (epidemic significance), ctxA, tcpA were detected in samples from 3 patients and 2 contact persons. The isolated strains were identified as Vibrio cholerae O1 Eltor Inaba in two cases, and in one case – as Vibrio cholerae O1 Eltor Hykoshima, Heiberg group I, toxigenic, hemolysis negative in Greig test, virulent, highly sensitive to ciprofloxacin, doxycilin, erythromycin, tetracycline and moderately sensitive to levomycetin. It was established that the country of export in all the cases was India. Relevant anti-epidemic and preventive measures were undertaken to localize and eradicate the foci in order to prevent possible threat of epidemic spread of infections among the population.

scholarly journals Dominant Vibrio cholerae phage exhibits lysis inhibition sensitive to disruption by a defensive phage satellite

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Stephanie G Hays ◽  
Kimberley D Seed
Keyword(s):  
Vibrio Cholerae ◽  
Diarrheal Disease ◽  
Mobile Genetic Elements ◽  
Dynamic Environments ◽  
Etiological Agent ◽  
Clinical Samples ◽  
Environmental Sensing ◽  
Cholera Vibrio ◽  
Defensive Function ◽  
Lysis Inhibition

Bacteria, bacteriophages that prey upon them, and mobile genetic elements (MGEs) compete in dynamic environments, evolving strategies to sense the milieu. The first discovered environmental sensing by phages, lysis inhibition, has only been characterized and studied in the limited context of T-even coliphages. Here, we discover lysis inhibition in the etiological agent of the diarrheal disease cholera, Vibrio cholerae, infected by ICP1, a phage ubiquitous in clinical samples. This work identifies the ICP1-encoded holin, teaA, and antiholin, arrA, that mediate lysis inhibition. Further, we show that an MGE, the defensive phage satellite PLE, collapses lysis inhibition. Through lysis inhibition disruption a conserved PLE protein, LidI, is sufficient to limit the phage produced from infection, bottlenecking ICP1. These studies link a novel incarnation of the classic lysis inhibition phenomenon with conserved defensive function of a phage satellite in a disease context, highlighting the importance of lysis timing during infection and parasitization.

A. LECTINS IN THE IMPLEMENTATION OF ANTI-LACTOFERRIN ACTIVITY OF VIBRIO CHOLERAE

2017 ◽  
pp. 50-53
Author(s):  
V.A. Korshenko ◽  
I.Ya. Cherepakhina
Keyword(s):  
Protein Binding ◽  
Vibrio Cholerae ◽  
Human Body ◽  
Active Sites ◽  
Target Cells ◽  
Initial Link ◽  
Lectin Receptors ◽  
Cholera Vibrio ◽  
Covalent Structure ◽  
El Tor

Anti-lactoferrin activity (AlfA) is one of the factors contributing to the persistence of V. cholerae in human body in formation of human vibriocarriers. It is shown that in the AlfA mechanism cholera vibrio lectins are participating as an initial link specifically binding to lactoferrin at the surface of microbial cells, providing for subsequent cleavage of this protein with the help of V. cholerae exoproteases. Lectins are proteins or glycoproteins of non-immune class, capable to reversibly bind to the carbohydrate fraction of glycoconjugates without breaking the covalent structure of any of the recognizable glycosyl ligands. As glycoproteins, lectins ensure the complementary highly specific carbohydrate-protein binding of the active sites of target cells (namely lactoferrin). It is proved that all V. cholerae El Tor and Bengal strains possess hexose-specific lectin receptors (especially mannose). Atoxigenic V. cholerae O1 and O139 strains possess, in addition to hexose receptors, lectins specific to aminosugars.

Sign in / Sign up

Export Citation Format

Share Document