Displaying publications 1 - 20 of 240 in total

Abstract:
Sort:
  1. Identification of Vibrio parahaemolyticus isolates by PCR targeted to the toxR gene and detection of virulence genes
    Zulkifli, Y., Alitheen, N.B., Son, R., Yeap, S.K., Lesley, M.B., Raha, A.R.
    International Food Research Journal, 2009;16(3):289-296.
    MyJurnal
    Vibrio parahaemolyticus is a gram negative bacterium and causes gastrointestinal illness in humans. In this study, twenty five out of fifty cockle samples from Padang, Indonesia produced purple colonies when they were grown on selective medium, CHROMagarTM Vibrio. Specific–PCR for toxR gene detection gave positive results in which a band with 368 base pairs size appeared on the gel for all the isolates that confirmed the presence of V. parahaemolyticus. In the virulence properties test, all the isolates showed negative results for tdh and trh genes detection. The results indicate that the isolates under this study do not contain virulence properties that correlate to the ability of infection and diseases, which means that they are nonpathogenic.
    Matched MeSH terms: Vibrio parahaemolyticus
  2. Fulltext Antibiotic resistance and plasmid profiling of Vibrio parahaemolyticus isolated from cockles in Padang, Indonesia
    Zulkifli, Y., Alitheen, N.B., Raha, A.R., Yeap, S.K., Marlina, Son, R., et al.
    International Food Research Journal, 2009;16(1):53-58.
    MyJurnal
    Vibrio parahaemolyticus is one of the most widely recognized pathogenic Vibrio species due to numerous outbreaks and its’ wide occurrence in marine environment. In this study, 32 isolates of V. parahaemolyticus isolated from cockles were tested for sensitivity to 16 antibiotics and the presence of plasmids. All the isolates were multi-resistance, defined as resistant to atleast three different antibiotics with multiple antibiotic resistance indexes ranging from 0.31 to 0.69, indicating the isolates originate from high risk sources of contamination where antibiotics are often used. In the plasmid profiling test, only 15 isolates (47%) harbored plasmid DNA, which ranged in size from 2.7 to 56.2 kb, separating the isolates into 14 plasmid profiles. Hence, food contaminated with antibiotic resistant V. parahaemolyticus could be a major threat to public health due to the distinct possibility that they can be a significant reservoir of genes encoding antibiotic resistance determinants that can be transferred intra or interspecies. As in many developing countries, raw food hygiene and antimicrobial resistance epidemiology is still in the infancy stage in the locality of the study and thus our data provide a current baseline profile of antimicrobial resistance and plasmid of V. parahaemolyticusfrom cockles in Padang, Indonesia.
    Matched MeSH terms: Vibrio parahaemolyticus
  3. Administration of Bacillus subtilis strains in the rearing water enhances the water quality, growth performance, immune response, and resistance against Vibrio harveyi infection in juvenile white shrimp, Litopenaeus vannamei
    Zokaeifar H, Babaei N, Saad CR, Kamarudin MS, Sijam K, Balcazar JL
    Fish Shellfish Immunol, 2014 Jan;36(1):68-74.
    PMID: 24161773 DOI: 10.1016/j.fsi.2013.10.007
    In this study, vegetative cell suspensions of two Bacillus subtilis strains, L10 and G1 in equal proportions, was administered at two different doses 10(5) (BM5) and 10(8) (BM8) CFU ml(-1) in the rearing water of shrimp (Litopenaeus vannamei) for eight weeks. Both probiotic groups showed a significant reduction of ammonia, nitrite and nitrate ions under in vitro and in vivo conditions. In comparison to untreated control group, final weight, weight gain, specific growth rate (SGR), food conversion ratio (FCR) and digestive enzymatic activity were significantly greater in the BM5 and BM8 groups. Significant differences for survival were recorded in the BM8 group as compared to the control. Eight weeks after the start of experiment, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 80%, whereas cumulative mortality of the shrimp that had been given probiotics was 36.7% with MB8 and 50% with MB5. Subsequently, real-time RT-PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and β-1,3-glucan- binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was only significantly up-regulated in the BM5 group compared to the BM8 and control groups. These results suggest that administration of B. subtilis strains in the rearing water confers beneficial effects for shrimp aquaculture, considering water quality, growth performance, digestive enzymatic activity, immune response and disease resistance.
    Matched MeSH terms: Vibrio/immunology*; Vibrio Infections/immunology*; Vibrio Infections/virology
  4. Fulltext Effects of Bacillus subtilis on the growth performance, digestive enzymes, immune gene expression and disease resistance of white shrimp, Litopenaeus vannamei
    Zokaeifar H, Balcázar JL, Saad CR, Kamarudin MS, Sijam K, Arshad A, et al.
    Fish Shellfish Immunol, 2012 Oct;33(4):683-9.
    PMID: 22659618 DOI: 10.1016/j.fsi.2012.05.027
    We studied the effect of two probiotic Bacillus subtilis strains on the growth performance, digestive enzyme activity, immune gene expression and disease resistance of juvenile white shrimp (Litopenaeus vannamei). A mixture of two probiotic strains, L10 and G1 in equal proportions, was administered at two different doses 10(5) (BM5) and 10(8) (BM8) CFU g(-1) feed to shrimp for eight weeks. In comparison to untreated control group, final weight, weight gain and digestive enzyme activity were significantly greater in shrimp fed BM5 and BM8 diets. Significant differences for specific growth rate (SGR) and survival were recorded in shrimp fed BM8 diet as compared with the control; however, no significant differences were recorded for food conversion ratio (FCR) among all the experimental groups. Eight weeks after the start of the feeding period, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 63.3%, whereas cumulative mortality of the shrimp that had been given probiotics was 20.0% with BM8 and 33.3% with BM5. Subsequently, real-time PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was significantly up-regulated (P 
    Matched MeSH terms: Vibrio/immunology
  5. Fulltext Selection and identification of non-pathogenic bacteria isolated from fermented pickles with antagonistic properties against two shrimp pathogens
    Zokaeifar H, Balcázar JL, Kamarudin MS, Sijam K, Arshad A, Saad CR
    J Antibiot (Tokyo), 2012 Jun;65(6):289-94.
    PMID: 22491136 DOI: 10.1038/ja.2012.17
    In this study, potential probiotic strains were isolated from fermented pickles based on antagonistic activity against two shrimp pathogens (Vibrio harveyi and Vibrio parahaemolyticus). Two strains L10 and G1 were identified by biochemical tests, followed by16S ribosomal RNA gene sequence analysis as Bacillus subtilis, and characterized by PCR amplification of repetitive bacterial DNA elements (Rep-PCR). Subsequently, B. subtilis L10 and G1 strains were tested for antibacterial activity under different physical conditions, including culture medium, salinity, pH and temperature using the agar well diffusion assay. Among the different culture media, LB broth was the most suitable medium for antibacterial production. Both strains showed the highest level of antibacterial activity against two pathogens at 30 °C and 1.0% NaCl. Under the pH conditions, strain G1 showed the greatest activity against V. harveyi at pH 7.3-8.0 and against V. parahaemolyticus at pH 6.0-8.0, whereas strain L10 showed the greatest activity against two pathogens at pH 7.3. The cell-free supernatants of both strains were treated with four different enzymes in order to characterize the antibacterial substances against V. harveyi. The result showed considerable reduction of antibacterial activity for both strains, indicating the proteinaceous nature of the antibacterial substances. A wide range of tolerance to NaCl, pH and temperature was also recorded for both strains. In addition, both strains showed no virulence effect in juvenile shrimp Litopenaeus vannamei. On the basis of these results and safety of strains to L. vannamei, they may be considered for future challenge experiments in shrimp as a very promising alternative to the use of antibiotics.
    Matched MeSH terms: Vibrio/growth & development*
  6. Fulltext Influencing factors for cholera and diarrhoea: water sanitation and hygiene in impoverished rural villages of Beluran District, Sabah Malaysia
    Zin, Thant, SabaiAung, Tin, Sahipudin Saupin, Myint, Than, KhinSN, Daw, Aung, Meiji Soe, et al.
    Malaysian Journal of Public Health Medicine, 2015;15(1):0-0.
    MyJurnal
    The lower percentage of water, sanitation and hygiene are the root causes of diarrhoea and cholera. Cholera is a sudden onset of acute watery diarrhoea which can progress to severe dehydration and death if untreated. The current pandemic, Vibrio Cholera O1 started in 1961. This study explores water, sanitation, hygiene and cholera and diarrhoea in three affected villages of Beluran District, Sabah Malaysia to support effective and timely public health intervention. This cross sectional study uses purposive sampling. All (114) households were interviewed and household water samples collected. The study reported lower coverage improved sanitation facilities (35.3% to 52.3%), no latrine at home (37% to 63%), improved water supply (52% to 60%), and prevalence of hand washing after toilet (57% - 74%). For water quality, Ecoli was present in household water (32% to 37%) but Vibrio cholerae was not isolated in any of the water samples tested. Statistically significant associations were found for; 1) occupation−nonagriculture and unimproved sanitation facility and 2) house ownership and correct knowledge of ORS preparation. Predictors for household water quality were: latrine at home, and improved household toilet. Aggressive strategies to improve water supply, sanitation and hygiene−hand washing after toilet−were recommended for future prevention of cholera and diarrhoea in the affected area.
    Matched MeSH terms: Vibrio cholerae
  7. Fulltext Contributions of tropodithietic acid and biofilm formation to the probiotic activity of Phaeobacter inhibens
    Zhao W, Dao C, Karim M, Gomez-Chiarri M, Rowley D, Nelson DR
    BMC Microbiol, 2016 Jan 05;16:1.
    PMID: 26728027 DOI: 10.1186/s12866-015-0617-z
    The probiotic bacterium Phaeobacter inhibens strain S4Sm, isolated from the inner shell surface of a healthy oyster, secretes the antibiotic tropodithietic acid (TDA), is an excellent biofilm former, and increases oyster larvae survival when challenged with bacterial pathogens. In this study, we investigated the specific roles of TDA secretion and biofilm formation in the probiotic activity of S4Sm.
    Matched MeSH terms: Vibrio/physiology; Vibrio Infections/drug therapy; Vibrio Infections/microbiology; Vibrio Infections/veterinary*
  8. Fulltext Phenotypic and genomic characterization of a Vibrio parahaemolyticus strain causing disease in Penaeus vannamei provides insights into its niche adaptation and pathogenic mechanism
    Zhang X, Sun J, Chen F, Qi H, Chen L, Sung YY, et al.
    Microb Genom, 2021 05;7(5).
    PMID: 33952389 DOI: 10.1099/mgen.0.000549
    The virulence of Vibrio parahaemolyticus is variable depending on its virulence determinants. A V. parahaemolyticus strain, in which the virulence is governed by the pirA and pirB genes, can cause acute hepatopancreatic necrosis disease (AHPND) in shrimps. Some V. parahaemolyticus that are non-AHPND strains also cause shrimp diseases and result in huge economic losses, while their pathogenicity and pathogenesis remain unclear. In this study, a non-AHPND V. parahaemolyticus, TJA114, was isolated from diseased Penaeus vannamei associated with a high mortality. To understand its virulence and adaptation to the external environment, whole-genome sequencing of this isolate was conducted, and its phenotypic profiles including pathogenicity, growth characteristics and nutritional requirements were investigated. Shrimps following artificial infection with this isolate presented similar clinical symptoms to the naturally diseased ones and generated obvious pathological lesions. The growth characteristics indicated that the isolate TJA114 could grow well under different salinity (10-55 p.p.t.), temperature (23-37 °C) and pH (6-10) conditions. Phenotype MicroArray results showed that this isolate could utilize a variety of carbon sources, amino acids and a range of substrates to help itself adapt to the high hyperosmotic and alkaline environments. Antimicrobial-susceptibility test showed that it was a multidrug-resistant bacterium. The whole-genomic analysis showed that this V. parahaemolyticus possessed many important functional genes associated with multidrug resistance, stress response, adhesions, haemolysis, putative secreted proteases, dedicated protein secretion systems and a variety of nutritional metabolic mechanisms. These annotated functional genes were confirmed by the phenotypic profiles. The results in this study indicated that this V. parahaemolyticus isolate possesses a high pathogenicity and strong environmental adaptability.
    Matched MeSH terms: Vibrio parahaemolyticus/genetics*
  9. Fulltext A fatal case of Vibrio vulnificus cellulitis with septicaemia
    Zetti ZR, Norazlah B, Raha AR
    Med J Malaysia, 2009 Sep;64(3):246-7.
    PMID: 20527281 MyJurnal
    Vibrio vulnificus is a gram-negative marine bacterium that may cause local wound infection, distinctive soft tissue infection, gastroenteritis and septicaemia with a high mortality rate. A healthy man presented with severe abdominal pain, diarrhoea and fever followed by development of multiple blisters, cellulitis and necrotizing fasciitis of the lower limbs, who progressed rapidly to fulminant sepsis caused by this organism. Vibrio vulnificus septicaemia should be suspected in the presence of sepsis and progressive soft-tissue infection with recent history of raw seafood consumption.
    Matched MeSH terms: Vibrio Infections/diagnosis*; Vibrio vulnificus/isolation & purification*
  10. Fulltext Genetic diversity of toxigenic Vibrio cholerae O1 from Sabah, Malaysia 2015
    Zaw MT, Emran NA, Ibrahim MY, Suleiman M, Awang Mohd TA, Yusuff AS, et al.
    J Microbiol Immunol Infect, 2019 Aug;52(4):563-570.
    PMID: 29428381 DOI: 10.1016/j.jmii.2018.01.003
    BACKGROUND: Cholera is an important health problem in Sabah, a Malaysian state in northern Borneo; however, Vibrio cholerae in Sabah have never been characterized. Since 2002, serogroup O1 strains having the traits of both classical and El Tor biotype, designated as atypical El Tor biotype, have been increasingly reported as the cause of cholera worldwide. These variants are believed to produce clinically more severe disease like classical strains.

    PURPOSE: The purpose of this study is to investigate the genetic diversity of V.cholerae in Sabah and whether V.cholerae in Sabah belong to atypical El Tor biotype.

    METHODS: ERIC-PCR, a DNA fingerprinting method for bacterial pathogens based on the enterobacterial repetitive intergenic consensus sequence, was used to study the genetic diversity of 65 clinical V.cholerae O1 isolates from 3 districts (Kudat, Beluran, Sandakan) in Sabah and one environmental isolate from coastal sea water in Kudat district. In addition, we studied the biotype-specific genetic traits in these isolates to establish their biotype.

    RESULTS: Different fingerprint patterns were seen in isolates from these three districts but one of the patterns was seen in more than one district. Clinical isolates and environmental isolate have different patterns. In addition, Sabah isolates harbor genetic traits specific to both classical biotype (ctxB-1, rstRCla) and El Tor biotype (rstRET, rstC, tcpAET, rtxC, VC2346).

    CONCLUSION: This study revealed that V.cholerae in Sabah were genetically diverse and were atypical El Tor strains. Fingerprint patterns of these isolates will be useful in tracing the origin of this pathogen in the future.

    Matched MeSH terms: Vibrio cholerae O1/genetics*; Vibrio cholerae O1/isolation & purification
  11. Fulltext Metagenomic data on Anadara granosa associated bacterial communities using culture dependent approaches and 16S rRNA sequencing
    Zarkasi KZ, Halim MA, Nazari TF, Daud F
    Data Brief, 2018 Aug;19:514-519.
    PMID: 29900350 DOI: 10.1016/j.dib.2018.05.052
    This article contains data on the bacterial communities and its diversity associated with Anadara granosa. The A. granosa samples were obtained from two major estuaries in Penang, Malaysia using a culture dependent and 16S rRNA Illumina sequencing approaches. A. granosa, a commercial blood cockles and popular seafoods, is fragile to the surrounding environments. Thus, our research focused to better understand the bacterial communities and it diversity in the A. granosa, as well as on the generation of a metagenomic library from A. granosa to further understanding on it diversity. The bacteria Vibrionaceae (34.1%) was predominant in the A. granosa from both environments followed by Enterobacteriaceae (33.3%) and Bacillaceae (16.75%). Vibrio sp., Klebsiella sp., and Bacillus subtilis were the most abundant species present. The data generated in this research is the first metagenomic examination of A. granosa and will provide as a baseline to understand the bacterial communities associated with A. granosa and its surrounding natural environments.
    Matched MeSH terms: Vibrio; Vibrionaceae
  12. Oral vaccination with Lactococcus lactis expressing the Vibrio cholerae Wzm protein to enhance mucosal and systemic immunity
    Zamri HF, Shamsudin MN, Rahim RA, Neela V
    Vaccine, 2012 May 2;30(21):3231-8.
    PMID: 22426330 DOI: 10.1016/j.vaccine.2012.02.012
    A gene associated with lipopolysaccharide (LPS) transport was cloned from a local clinical Vibrio cholerae O1 strain of the Ogawa serotype by using the Lactococcus lactis nisin-controlled expression (NICE) system. The V. cholerae wzm gene, which codes for an integral membrane transporter protein, was expressed and targeted to the cytoplasmic membrane, and was crudely isolated through simple centrifugation and SDS solubilization. To examine seroreactivity of this construct, rabbits were orally fed with 10(9) cfu/ml of live, recombinant L. lactis carrying the wzm gene, induced with nisin prior to administration. Recombinant plasmids were retrieved from L. lactis cultured directly from stool samples of inoculated rabbits. Reverse-transcriptase PCR of wzm using the retrieved plasmids confirmed transcription of this gene, indicating viability and stability of the recombinants in vivo. The L. lactis-Wzm construct elicited substantial levels of IgG and sIgA, and challenge with virulent V. cholerae O1 evoked severe diarrhoea in the naive, non-immunised control group, but not in those fed with either recombinant or non-recombinant L. lactis. Oral administration with recombinant L. lactis expressing the V. cholerae wzm gene increases both systemic and mucosal immunity, whereas L. lactis itself appears capable of protecting against the diarrhoeal symptoms caused by V. cholerae. Wzm is a conserved membrane protein associated with the LPS endotoxin, and together with the food-grade L. lactis, represent an attractive target for the development of a safer, live anti-infective therapy against V. cholerae.
    Matched MeSH terms: Vibrio cholerae O1/genetics; Vibrio cholerae O1/immunology*
  13. Comparative genomic provides insight into the virulence and genetic diversity of Vibrio parahaemolyticus associated with shrimp acute hepatopancreatic necrosis disease
    Yu LH, Teh CSJ, Yap KP, Ung EH, Thong KL
    Infect Genet Evol, 2020 09;83:104347.
    PMID: 32360538 DOI: 10.1016/j.meegid.2020.104347
    Acute hepatopancreatic necrosis disease (AHPND) is an important shrimp disease of economic importance which causes mass mortality of cultivated penaeid shrimps in Southeast Asian countries, Mexico and South America. This disease was originally caused by Vibrio parahaemolyticus (VPAHPND) which is reported to harbour a transferable plasmid carrying the virulent PirAB-like toxin genes (pirABvp). However, little is known about the pathogenicity of VPAHPND. To extend our understanding, comparative genomic analyses was performed in this study to identify the genetic differences and to understand the phylogenetic relationship of VPAHPND strains. Seven Vibrio parahaemolyticus strains (five VPAHPND strains and two non-VPAHPND strains) were sequenced and 31 draft genomes of V. parahaemolyticus were retrieved from NCBI database and incorporated into the genomic comparison to elucidate their genomic diversity. The study showed that the genome sizes of the VPAHPND strains were approximately 5 Mbp. Ten sequence types (STs) were identified among the VPAHPND strains using in silico-Multilocus Sequence Typing analysis (MLST) and ST 970 was the predominant ST. Phylogenetic analysis based on MLST and single nucleotide polymorphisms (SNP) showed that the VPAHPND strains were genetically diverse. Based on the comparative genomic analysis, several functional proteins were identified from diiferent categories associated with virulence-related proteins, secretory proteins, conserved domain proteins, transporter proteins, and phage proteins. The CRISPR analysis showed that VPAHPND strains contained less number of CRISPRs elements than non-VPAHPND strains while six prophages regions were identified in the genomes, suggested the lack of CRISPR might promote prophage insertion. The genomic information in this study provide improved understanding of the virulence of these VPAHPND strains.
    Matched MeSH terms: Vibrio Infections/microbiology; Vibrio Infections/veterinary*; Vibrio parahaemolyticus/classification; Vibrio parahaemolyticus/genetics*; Vibrio parahaemolyticus/isolation & purification; Vibrio parahaemolyticus/pathogenicity*
  14. Dry-reagent gold nanoparticle-based lateral flow biosensor for the simultaneous detection of Vibrio cholerae serogroups O1 and O139
    Yu CY, Ang GY, Chua AL, Tan EH, Lee SY, Falero-Diaz G, et al.
    J Microbiol Methods, 2011 Sep;86(3):277-82.
    PMID: 21571011 DOI: 10.1016/j.mimet.2011.04.020
    Cholera is a communicable disease caused by consumption of contaminated food and water. This potentially fatal intestinal infection is characterised by profuse secretion of rice watery stool that can rapidly lead to severe dehydration and shock, thus requiring treatment to be given immediately. Epidemic and pandemic cholera are exclusively associated with Vibrio cholerae serogroups O1 and O139. In light of the need for rapid diagnosis of cholera and to prevent spread of outbreaks, we have developed and evaluated a direct one-step lateral flow biosensor for the simultaneous detection of both V. cholerae O1 and O139 serogroups using alkaline peptone water culture. Serogroup specific monoclonal antibodies raised against lipopolysaccharides (LPS) were used to functionalize the colloidal gold nanoparticles for dual detection in the biosensor. The assay is based on immunochromatographic principle where antigen-antibody reaction would result in the accumulation of gold nanoparticles and thus, the appearance of a red line on the strip. The dry-reagent dipstick format of the biosensor ensure user-friendly application, rapid result that can be read with the naked eyes and cold-chain free storage that is well-suited to be performed at resource-limited settings.
    Matched MeSH terms: Vibrio cholerae O1/immunology; Vibrio cholerae O1/isolation & purification*; Vibrio cholerae O139/immunology; Vibrio cholerae O139/isolation & purification*
  15. Multiplex electrochemical genosensor for identifying toxigenic Vibrio cholerae serogroups O1 and O139
    Yu CY, Ang GY, Yean CY
    Chem Commun (Camb), 2013 Mar 11;49(20):2019-21.
    PMID: 23370051 DOI: 10.1039/c3cc39144b
    We developed a multiplex enzyme-based electrochemical genosensor for sequence-specific detection of multiplex linear-after-the-exponential-PCR amplicons that targeted toxigenic Vibrio cholerae O1 and O139 using novel screen-printed gold electrode bisensors.
    Matched MeSH terms: Vibrio cholerae O1/genetics; Vibrio cholerae O1/isolation & purification*; Vibrio cholerae O139/genetics; Vibrio cholerae O139/isolation & purification*
  16. Enzymatic electrochemical detection of epidemic-causing Vibrio cholerae with a disposable oligonucleotide-modified screen-printed bisensor coupled to a dry-reagent-based nucleic acid amplification assay
    Yu CY, Ang GY, Chan KG, Banga Singh KK, Chan YY
    Biosens Bioelectron, 2015 Aug 15;70:282-8.
    PMID: 25835520 DOI: 10.1016/j.bios.2015.03.048
    In this study, we developed a nucleic acid-sensing platform in which a simple, dry-reagent-based nucleic acid amplification assay is combined with a portable multiplex electrochemical genosensor. Preparation of an amplification reaction mix targeting multiple DNA regions of interest is greatly simplified because the lyophilized reagents need only be reconstituted with ultrapure water before the DNA sample is added. The presence of single or multiple target DNAs causes the corresponding single-stranded DNA (ssDNA) amplicons to be generated and tagged with a fluorescein label. The fluorescein-labeled ssDNA amplicons are then analyzed using capture probe-modified screen-printed gold electrode bisensors. Enzymatic amplification of the hybridization event is achieved through the catalytic production of electroactive α-naphthol by anti-fluorescein-conjugated alkaline phosphatase. The applicability of this platform as a diagnostic tool is demonstrated with the detection of toxigenic Vibrio cholerae serogroups O1 and O139, which are associated with cholera epidemics and pandemics. The platform showed excellent diagnostic sensitivity and specificity (100%) when challenged with 168 spiked stool samples. The limit of detection was low (10 colony-forming units/ml) for both toxigenic V. cholerae serogroups. A heat stability assay revealed that the dry-reagent amplification reaction mix was stable at temperatures of 4-56 °C, with an estimated shelf life of seven months. The findings of this study highlight the potential of combining a dry-reagent-based nucleic acid amplification assay with an electrochemical genosensor in a more convenient, sensitive, and sequence-specific detection strategy for multiple target nucleic acids.
    Matched MeSH terms: Vibrio cholerae/genetics; Vibrio cholerae/isolation & purification*
  17. Antibiotic resistance and plasmid profiling of Vibrio spp. in tropical waters of Peninsular Malaysia
    You KG, Bong CW, Lee CW
    Environ Monit Assess, 2016 Mar;188(3):171.
    PMID: 26884358 DOI: 10.1007/s10661-016-5163-0
    Vibrio species isolated from four different sampling stations in the west coast of Peninsular Malaysia were screened for their antimicrobial resistance and plasmid profiles. A total of 138 isolates belonging to 15 different species were identified. Vibrio campbellii, V. parahaemolyticus, V. harveyi, and V. tubiashii were found to predominance species at all stations. High incidence of erythromycin, ampicillin, and mecillinam resistance was observed among the Vibrio isolates. In contrast, resistance against aztreonam, cefepime, streptomycin, sulfamethoxazole, and sulfonamides was low. All the Vibrio isolates in this study were found to be susceptible to imipenem, norfloxacin, ofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and oxytetracycline. Ninety-five percent of the Vibrio isolates were resistant to one or more different classes of antibiotic, and 20 different resistance antibiograms were identified. Thirty-two distinct plasmid profiles with molecular weight ranging from 2.2 to 24.8 kb were detected among the resistance isolates. This study showed that multidrug-resistant Vibrio spp. were common in the aquatic environments of west coast of Peninsular Malaysia.
    Matched MeSH terms: Vibrio/classification; Vibrio/genetics*
  18. Fulltext Molecular characterisation of Vibrio parahaemolyticus carrying tdh and trh genes using ERIC-, RAPD- and BOX-PCR on local Malaysia bloody clam and Lala
    Yoke-Kqueen, C., Teck-Ee, K., Son, R, Yoshitsugu, N., Mitsuaki, N.
    International Food Research Journal, 2013;20(6):3299-3305.
    MyJurnal
    Molecular typing methods have been widely applied for many purposes. In this study, such methods were adopted as DNA fingerprinting tools to determine the origin and divergence of virulent Vibrio parahaemolyticus strains found in local seafood. Although not all strain carry virulent tdh and trh gene, increasing prevalence demands an effective fingerprinting scheme which can constantly monitor and trace the sources of such emerging food pathogens. By using ERIC-, RAPD-, and BOX-PCR methods, 33 Vibrio parahaemolyticus isolates from local Malaysia bloody clam (Anadara granosa) and Lala (Orbicularia orbiculata) with confirmed presence of tdh and trh gene were characterised, followed by determination of clonal relatedness among virulent strains using cluster analysis and discriminatory index. This study also involved application of Immunomagnetic Separation (IMS) Method which significantly improved the specificity of strain isolation. Cluster analysis using Unweighted Pair Group Mathematical Averaging (UPGMA) and Dice Coefficient shown clustering according to isolation food source, IMS level and haemolysin gene possessed. Nevertheless, different DNA fingerprinting methods generated different clustering at different similarity cut-off percentage, regardless as individual or as composite dendrograms. ERIC- and RAPD-PCR composite fingerprinting relatively shown the highest discriminatory index at following similarity cutoff percentage: 0.68 at 50%; 0.83 at 65%; and 0.93 at 75%. Discriminatory power increased with similarity cut-off percentage. However, result also suggested that BOX-PCR might be an effective fingerprinting tool, as it generated three clusters with no single-colony isolate at 70% similarity cut-off. This study not only achieved its objective to determine clonal relatedness among virulent strains from local seafood via characterisation, but also speculated the best possible combination of molecular typing methods to effectively do so.
    Matched MeSH terms: Vibrio parahaemolyticus
  19. Ultrasensitive pathogen detection with a rolling circle amplification-empowered multiplex electrochemical DNA sensor
    Yeap CSY, Chaibun T, Lee SY, Zhao B, Jan Y, La-O-Vorakiat C, et al.
    Chem Commun (Camb), 2021 Nov 16;57(91):12155-12158.
    PMID: 34726213 DOI: 10.1039/d1cc05181d
    We report a highly sensitive and selective multiplex assay by empowering an electrochemical DNA sensor with isothermal rolling circle amplification. The assay could simultaneously detect and discriminate three common entero-pathogens in a single reaction, with femtomolar sensitivity. It is useful for field- or resource-limited settings.
    Matched MeSH terms: Vibrio cholerae/isolation & purification*
  20. Enzyme-linked amperometric electrochemical genosensor assay for the detection of PCR amplicons on a streptavidin-treated screen-printed carbon electrode
    Yean CY, Kamarudin B, Ozkan DA, Yin LS, Lalitha P, Ismail A, et al.
    Anal Chem, 2008 Apr 15;80(8):2774-9.
    PMID: 18311943 DOI: 10.1021/ac702333x
    A general purpose enzyme-based amperometric electrochemical genosensor assay was developed wherein polymerase chain reaction (PCR) amplicons labeled with both biotin and fluorescein were detected with peroxidase-conjugated antifluorescein antibody on a screen-printed carbon electrode (SPCE). As a proof of principle, the response selectivity of the genosensor was evaluated using PCR amplicons derived from lolB gene of Vibrio cholerae. Factors affecting immobilization, hybridization, and nonspecific binding were optimized to maximize sensitivity and reduce assay time. On the basis of the background amperometry signals obtained from nonspecific organisms and positive signals obtained from known V. cholerae, a threshold point of 4.20 microA signal was determined as positive. Under the optimum conditions, the limit of detection (LOD) of the assay was 10 CFU/mL of V. cholerae. The overall precision of this assay was good, with the coefficient of variation (CV) being 3.7% using SPCE and intermittent pulse amperometry (IPA) as an electrochemical technique. The assay is sensitive, safe, and cost-effective when compared to conventional agarose gel electrophoresis, real-time PCR, and other enzyme-linked assays for the detection of PCR amplicons. Furthermore, the use of a hand-held portable reader makes it suitable for use in the field.
    Matched MeSH terms: Vibrio cholerae/genetics
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links