ISOLATION AND IDENTIFICATION OF Vibrio parahaemolyticus FROM FLOWER CRAB (Portunus pelagicus) IN NEGERI SEMBILAN AND SELANGOR

2019 ◽  
Vol 7 (SI-TeMIC18) ◽  
Author(s):  
Nur Rabiatul Adawiah B Mohammad Noor ◽  
Sahilah Abd. Mutalib ◽  
Norrakiah Abdullah Sani

This study was conducted to determine the presence of Vibrio parahaemolyticus on 30 samples of flower crab (Portunus pelagicus) collected from Negeri Sembilan (n = 15) and Selangor (n = 15) from March to July 2014. A total of 193 isolates of Vibrio sp. were isolated from the thiosulphate citrate bile-salt (TCBS) agar medium. Of 79 Vibrio isolates were identified as V. parahaemolyticus through biochemical testing methods. In V. parahaemolyticus identification by detection of regulatory gene toxR, 51 (64.6%) of 79 isolates contained toxR gene while none of the isolates contained virulence gene of tdh dan trh. by targeting toxR gene which produced amplicons of 368 bp molecular weight. All V. parahaemolyticus isolates were negative for tdh and trh genes. Keywords: Vibrio parahaemolyicus, flower crab, toxR, trh, tdh

1967 ◽  
Vol 13 (12) ◽  
pp. 1671-1682 ◽  
Author(s):  
Richard F. Unz ◽  
Norman C. Dondero

Direct, single-cell isolations of bacteria, primarily from natural, branching, waste water zoogloeas, were made by micromanipulation. Isolations were also made by conventional methods. Direct isolates were classified, chiefly with regard to zoogloea formation, into two groups designated group I (zoogloea-forming) and group II (nonzoogloea-forming). Casitone – glycerol – yeast autolysate agar medium was best for the isolation of group I bacteria. Group I isolates reduced nitrate to gas, possessed urease and catalase, and gave positive oxidase reactions. They were generally able to hydrolyze gelatin but, with one exception, did not produce acid from carbohydrates, and none produced H2S, indole, or acetylmethylcarbinol or utilized Koser citrate. Group II strains were usually more diverse on differential tests and could be distinguished from group I strains. Group I strains were characterized as Zoogloea strains and were found to be the predominant bacteria in natural, branching, zoogloeal colonies.


2014 ◽  
pp. 259-269 ◽  
Author(s):  
Vladislava Soso ◽  
Marija Skrinjar ◽  
Nevena Blagojev ◽  
Slavica Veskovic-Moracanin

As the aflatoxins represent a health-risk for humans because of their proven carcinogenicity, food-borne fungi that produce them as secondary metabolites, mainly Aspergillus flavus and Aspergillus parasiticus, have to be isolated and identified. The best argument for identifying problem fungi is that it indicates control points within the food system as part of a hazard analysis critical control point (HACCP) approach. This assumes there is a close link between fungus and toxin. Conventional methods for isolation and identification of fungi are time consuming and require admirably dedicated taxonomists. Hence, it is imperative to develop methodologies that are relatively rapid, highly specific and as an alternative to the existing methods. The polymerase chain reaction (PCR) facilitates the in vitro amplification of the target sequence. The main advantages of PCR is that organisms need not be cultured, at least not for a long time, prior to their detection, target DNA can be detected even in a complex mixture, no radioactive probes are required, it is rapid, sensitive and highly versatile. The gene afl-2 has been isolated and shown to regulate aflatoxin biosynthesis in A. flavus. Also, the PCR reaction was targeted against aflatoxin synthesis regulatory gene (aflR1) since these genes are nearly identical in A. flavus and A. parasiticus in order to indicate the possibility of detection of both the species with the same PCR system (primers/reaction). [Projekat Ministarstva nauke Republike Srbije, br. III46009] <br><br><font color="red"><b> This article has been retracted. Link to the retraction <u><a href="http://dx.doi.org/10.2298/APT1647265E">10.2298/APT1647265E</a><u></b></font>


2020 ◽  
Vol 1 (7) ◽  
pp. 320-329
Author(s):  
Ayman A Elshayeb ◽  
Amna Elfatih ◽  
Karimeldin MA Salih ◽  
Nada SE Mustafa4

Introduction: The invasion of bacteriophage on the associated host bacterium depends on their receptors' orientation that adsorb them to cell surface. During phage replication a valuable number of proteins acts as lytic enzymes for host puncher at the beginning of the infection and other for burst after lytic cycle compilation. Accordingly, the proteomic relationship among phage and bacterium proteins could easily be studied by their protein profiles analysis. Objective: To detect bacteriophages functional enzymes during lytic cycle. Methods: The isolation and identification of Escherichia coli and their parasitic T7 phage group was done using bacterial culture and common plaque assay techniques. The investigations and protein-protein interactions' assays were inveterate by proteins profile of phage and bacterium using Sodium Dodecyl Sulphate Poly Acrylamide Gel Electrophoresis (SDS-PAGE) to find out their molecular weights, where the scaled location of each mobile band was compared to the standards of identified proteins weights in the molecular ladder. Thereafter, Protein model's assembly and bands migration was done by computer analytical software. Results: Mobilization of the phage' proteins inside the Two Dimensions (2D) gel ranged between 60 and 12 kDa where a model of 4 main bands with molecular weights of (46, 35, 24 and 14 kDa) is corresponded to the host ones, where pure 9 bands with molecular weight ranged between 96-24 kDa. The computational model analysis showed common shared molecular masses of 47, 34 and 16 kDa on plot area of the phage and the bacterium. Model interpretation confirmed that proteins ranged from 47.7 to 34.3 kDa resembles 43.3% of whole phage's proteins that assembled the capsid head and the coil, while the molecular weight mass of 22.5 formed the tail's proteins. The lytic enzymes' molecular weight was ranged between 18-14 kDa according to the function of the enzyme. The study revealed that the 34 kDa band has the common shared peak between T7 phage group and associated Escherichia coli host. Conclusion: Functional models of analysed proteins during phage assembly, ensures lytic enzymes are built in the capsid head and the lysozyme in the tail, they facilitate the enzymatic decay for bacterial host. This enzymatic function is related to the lytic cycle of the bacteriophages and their phenomenon in employing the bacterial DNA in proteins manufacturing during their replication inside host.


Author(s):  
Yiquan Zhang ◽  
Lingfei Hu ◽  
George Osei-Adjei ◽  
Ying Zhang ◽  
Wenhui Yang ◽  
...  

1971 ◽  
Vol 34 (9) ◽  
pp. 447-452 ◽  
Author(s):  
R. Nickelson ◽  
C. Vanderzant

This review presents current information on the taxonomic position, biochemical characteristics, distribution, isolation and identification procedures, pathogenicity, and serology of Vibrio parahaemolyticus. In the past, V. parahaemolyticus was associated primarily with outbreaks of gastroenteritis in Japan caused by consumption of seafoods and other salted foods. In recent years, this organism has been isolated from marine environments and seafoods in many countries, including the United States. In addition to gastroenteritis, some strains may cause localized tissue infections in humans and cause death of crab and shrimp. In the United States, V. parahaemolyticus has been incriminated in unconfirmed outbreaks of foodborne illness associated with consumption of shellfish. Isolation procedures based on direct plating of food homogenates on selective media with or without prior enrichment in broth media are available. Suspect colonies are confirmed by biochemical tests and fluorescent antibody technique. Although antisera (7 polyvalent and 47 monovalent) for serological grouping of strains of V. parahaemolyticus are available, their usefulness in diagnostic procedures is at the present uncertain.


Author(s):  
Shaohua Yang ◽  
Yu Wu ◽  
Jun Yang ◽  
Rong Yan ◽  
Yinghui Bao ◽  
...  

In this study, the purification and characterization of an extracellular enzyme form Aspergillus niger was performed. With an optimized protocol, it was conducted a 42.6-fold purification with a yield of 26.2%. The purified lipase had a monomeric molecular weight of 40.5kDa and an isoelectric point of 6.01, and its maximum enzyme activity could be achieved at 40°C and pH 7.5-9.0. The enzyme could be activated by Ca2+, Mg2+ and Fe2+, while its activity could be inhibited by Zn2+ and Cu2+. Additionally, organic compounds exerted an inhibitory effect on the enzyme activity in a descending order of methanol, ethanol, DMSO, EDTA, acetone. Meanwhile, the specificity analysis of the enzyme indicated a preference to tributyrin and vegetable oils as well as long-chain fatty acid methyl esters (C12-C18). Most importantly, this enzyme could successfully transform deoxynivalenol (DON). Using HPLC analysis,it was detected a biotransformation rate of more than 70%.The liquid chromatography-mass spectrometry (LC-MS) analysis showed that the molecular weight of the transformation product was 18.0 larger than that of DON, indicating that DON could be hydrolyzed by the enzyme. Overall, the proposed method here provides a new avenue for reducing the toxicity of DON, which appears to have a wide application outlook for DON biotransformation.


2009 ◽  
Vol 75 (19) ◽  
pp. 6268-6274 ◽  
Author(s):  
Munirul Alam ◽  
Wasimul B. Chowdhury ◽  
N. A. Bhuiyan ◽  
Atiqul Islam ◽  
Nur A. Hasan ◽  
...  

ABSTRACT Forty-two strains of Vibrio parahaemolyticus were isolated from Bay of Bengal estuaries and, with two clinical strains, analyzed for virulence, phenotypic, and molecular traits. Serological analysis indicated O8, O3, O1, and K21 to be the major O and K serogroups, respectively, and O8:K21, O1:KUT, and O3:KUT to be predominant. The K antigen(s) was untypeable, and pandemic serogroup O3:K6 was not detected. The presence of genes tox R and tlh were confirmed by PCR in all but two strains, which also lacked tox R. A total of 18 (41%) strains possessed the virulence gene encoding thermostable direct hemolysin (TDH), and one had the TDH-related hemolysin (trh) gene, but not tdh. Ten (23%) strains exhibited Kanagawa phenomenon that surrogates virulence, of which six, including the two clinical strains, possessed tdh. Of the 18 tdh-positive strains, 17 (94%), including the two clinical strains, had the seromarker O8:K21, one was O9:KUT, and the single trh-positive strain was O1:KUT. None had the group-specific or ORF8 pandemic marker gene. DNA fingerprinting employing pulsed-field gel electrophoresis (PFGE) of SfiI-digested DNA and cluster analysis showed divergence among the strains. Dendrograms constructed using PFGE (SfiI) images from a soft database, including those of pandemic and nonpandemic strains of diverse geographic origin, however, showed that local strains formed a cluster, i.e., “clonal cluster,” as did pandemic strains of diverse origin. The demonstrated prevalence of tdh-positive and diarrheagenic serogroup O8:K21 strains in coastal villages of Bangladesh indicates a significant human health risk for inhabitants.


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