Vibrio cholerae, detection

Palmer, L. M., and Colwell, R. R. (1991). Detection of luciferase gene sequence in nonluminescent Vibrio cholerae by colony hybridization and polymerase chain reaction. Appl. Environ. Microbiol. 57 1286-1293. 

Interestingly, they report that E. coli, a normal inhabitant of the mammalian gastrointestinal tract, produces anhydro-TTX. Unidentified sodium channel blockers have also been detected in cultures of Vibrio cholerae an estuarine bacterium and human enteropathogen (54). 

Fig. 4.—Mass Fragmentography (m/e 161) of Methylated Hexose Derivatives from the Disialosy] Ganglioside. [Top, before treatment with neuraminidase bottom, after treatment with Vibrio cholerae neuraminidase. The methylated hexose derivatives identified are (A) 2,4,6-tri-O-methylgalactose (B) 2,3,6-tri-O-methylglucose (C) 2,3,4,6-tetra-O-methylgalactose. The peaks eluting before C are unrelated signals that were also detected in a blank experiment employing the neuraminidase treatment. Conditions 3% of QF-1, at 190°. Reproduced, by permission, from Ref. 80.]...

A similar distribution of fatty acids has also been detected in lipid A of other bacteria (Fig. 5). Thus, in Fusobacterium nucleatum, 2 moles of (R)-3-OH-14 0 are ester-bound, one of which is 3-O-acylated by 14 0. In amide linkage, (R)-3-0(14 0)-16 0 is present. In Vibrio cholerae, a dimer of (R)-3-OH-12 0 is bound as an ester while (R)-3-0-(14 0)-14 0 and (R)-3-0-(16 0)-14 0 are amide-linked. The lipid A component of Chromobacterium violaceum possesses 2 moles of (R)-3-OH-10 0 in ester linkage. The amide-bound acyl groups are represented by (R)-3-0H-12 0 residues which are 3-0-acylated by 12 0 and (S)-2-OH-12 0. In P. mirabilis, 3-0H-14 0 is, like in Salmonella, ester-and amide-bound. In this case, however, exclusively 14 0 substitutes the 3-hydroxyl groups of both 0- and N-linked 3-OH-14 0. 

Adult-animal sera contain antibodies to a variety of polysaccharides, including those of human pathogenic bacteria, indicating that, to confer immunity, disease is not required. Robbins and coworkers7 212 were able to detect antibodies having a specificity for Vibrio cholerae... 

Jyoung. J.-Y, Hong, S., Lee, W., and Choi, J.W., 2006. Immunosensor for the detection of Vibrio cholerae 01 using surface plasmon resonance. Biosens. Bioelectron., 21, pp. 2315-2319. 

K8. Kobayashi, K., Seto, K., Ueguchi, M., Makino, M., Ishibashi, M., Akasaka, S., and Yamamoto, K., A new simple method of detecting cholera enterotoxin gene from Vibrio cholerae 01 isolates, lgaku noAyumi 150, 509-510 (1989). 

In the first primary structures of microbial sialidases, obtained by cloning and sequencing of the respective genes from Clostridium perfringens [769], Vibrio cholerae [770], Clostridium sordellii [77 ] and Salmonella typhimurium [772], an amino acid sequence motif was detected, which is repeated four-fold in each protein S-X-D-X-G-X-T-W [773]. This motif, named the Asp-box, was found in all 16 sialidases of animals, trypanosomes, and bacteria, which have so far been sequenced (see refs. [660,768] and Table 18). In viral sialidases, however, the motif was rarely detectable (e.g. only the sialidase from N9 influenza A virus strain exhibits the complete motif [786] and has probably undergone mutational alterations). 

Adsorption of antibodies was used to develop a sensor for the detection of Vibrio cholerae 0139 [92]. A fast detection method was required to measure and differentiate this strain with the Ogawa serotype of the bacteria. The sensor could measure the bacteria to 10 cells mL against a background of the... 

An outstanding example of DNA technology is the polymerase chain reaction (PCR). This is a technique for producing millions of copies of a single DNA molecule so that it can be analyzed almost as easily as a purified chemical substance. The Food and Drug Administration has developed and deployed in its field laboratories a PCR method for the detection of Vibrio cholerae in imported food (3). Practical experience with this and other methods will no doubt highlight areas where further technical improvements can be made for purposes of food analysis. 

Enterotoxins. Toxic proteins formed by bacteria with molecular masses in the range from 27000 to 30000 which are usually excreted into the medium ( exotoxins). E. can be taken up with contaminated food or be formed by the bacteria colonizing the intestinal walls. Finally, the bacteria can penetrate the intestinal walls and then start to excrete the E. Some E. are thermally very stable and survive when food is boiled. E. from Salmonella and Staphylococcus species are the most frequent causes of food poisoning. Shortly after uptake, the symptoms of nausea, vomiting, diarrhea, and circulatory complaints occur. Deaths are rare and occur only when the subject is already in a weakened state. The sites of attack by E. vary, e.g., at intestinal epithelial cells or in the vegetative nervous system. For the production of antitoxins, E. are obtained by lysis of bacterial cells or from cell-free culture filtrates. E. have been detected, e. g., in the following bacterial species Bacillus cereus, Clostridium perfringens, Escherichia coli. Vibrio cholerae. Staphylococcus aureus, and Streptococcus faecalis. 

Electrochemical genosensors for detection of various bacterial species have been described in Refs. 8 and 13-19. Reliable detection assa have been developed for pathogenic bacteria such as Salmonella sp, coli 0157 H7, Staphylococcus aureus and Vibrio cholerae that cause major worldwide foodbome outbreaks [8,13,16, 19,20]. 

In our recent articles, we described the detection of a food-borne pathogen. Vibrio cholerae, which causes cholera disease. The assay relied on detection of Vibrio cholerae-specihc PCR amplicons using an electrochemical genosensor on screen-printed carbon chips. The signal was measured by intermittent pulse amperometiy (IPA) using a portable handheld reader AndCare (Alderon, Durham, NC). 

These test strips were employed for the detection of human papilloma virus (amongst others) [32]. Haptenized DNA molecules (PCR amplicons from DNA samples of cervix carcinomas) were immuno-labeled with UCNPs. Subsequently, an LF assay was performed that resulted in a 100-fold improved sensitivity compared to established assays using gold nanoparticles. Improved sensitivity for amplified nucleic acid targets compared to immuno-gold and Cy5 detection-systems was also found in tests for Vibrio cholerae where attomole quantities of DNA could be detected [37]. 

Low, K.-F., Chuenrangsikul, K., Rijiravanich, P. et al. (2012) Electrochemical genosensor for specific detection of the food-borne pathogen, vibrio cholerae. World J. Microbiol. BiotechnoL, 28 (4), 1699-1706. 

Sialic acid was the first virus receptor identified. Hirst and McClelland and Hare discovered that influenza virus is able to hemagglutinate and that adsorbed virus is eluted from erythrocytes on incubation at 37°C, indicating an enzymatic destruction of a receptor substance on the cells [1, 2]. When a similar enzymatic activity was subsequently detected in Vibrio cholerae cultures, the term receptor-destroying enzyme was introduced [3]. The substance released by the viral enzyme from soluble hemagglutination inhibitors was initially characterized as a carbohydrate of low molecular weight [4] and then identified in crystalline form as A-acetyl-o-neuraminic acid [5]. Thus, it was clear that the receptor determinant of influenza virus was sialic acid and that the viral enzyme was a neuraminidase. Furthermore, for the first time an important biological function of sialic acid had been identified. 

Glycoproteins containing sialic acid may be detected by staining with a cationic carbocyanine dye before and after digestion with neuraminidase a change in the colour of the stain from blue to red-purple indicates the presence of sialic acid. The n.m.r. spectra of iV-acetylneuraminic acid and its methyl ester in DMSO and in water have indicated that the acid exists predominantly in the /S-form in solution. The finding supports the assumption that 7V-acetyl-neuraminic acid, produced by the enzymic cleavage of its a-ketosides, leaves the catalytic site of Vibrio cholerae neuraminidase as the j3-anomer. 

The initial symptoms of cholera resemble those of ETEC diarrhoea there is accumulation of fluid in the lumen of the intestine, as a result of the activation of adenylate cyclase in the intestinal mucosa by cholera entero-toxin. Large numbers of vibrios can be detected in the spaces between the intestinal villi. Organisms appear to be able to penetrate the mucus that lines the intestine and reach the crypts at the base of the villi. The prevalence of cholera in communities possessing contaminated drinking water, with its associated high mortality, particularly in infants, has prompted many studies of the organism and the host, in an attempt to explain the... 

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