Molecular analysis of a filamentous phage (fsl) of Vibrio cholerae O139.

A filamentous bacteriophage from Vibrio cholerae O139 strain A1-4450 was isolated (fsl). The phage fsl had a ssDNA genome and dsDNA as a replicative form (RF) in lysogenic host cell. The DNA sequence of fsl RF was determined.

Induction of fimbriated Vibrio cholerae O139.

Several fimbriated phases of Vibrio cholerae O139 strains were selectively induced and compared immunologically and biochemically with those of V. cholerae O1. Fimbrial antigens were detected on the surfaces of vibrio cells colonizing the epithelial cells of a rabbit small intestine.

A deviant mitochondrial genetic code in prymnesiophytes (yellow-algae): UGA codon for tryptophan.

The sequence of a representative mitochondrial gene COXI, encoding cytochrome c oxidase subunit I, was determined in five species that cover all the orders of the Prymnesiophyta with the exception of the Pavlovales. Through this analysis, we noticed that the 'stop' codon UGA appears frequently and, specifically, at conserved tryptophan (Trp) sites of the gene. We showed these sites were not edited in the corresponding mRNA in one of these species, Isochrysis galbana.

Characterization of filamentous phages of Vibrio cholerae O139 and O1.

We have analyzed our collection of Vibrio cholerae O139 strains to determine whether filamentous phages are produced in their culture supernatants, and whether any replicative form of DNA is detectable in cell lysates. Two types of filamentous phage, designated fs1 (6.4 kb) and fs2 (8.

Algae or protozoa: phylogenetic position of euglenophytes and dinoflagellates as inferred from mitochondrial sequences.

The chloroplasts of euglenophytes and dinoflagellates have been suggested to be the vestiges of endosymbiotic algae acquired during the process of evolution. However, the evolutionary positions of these organisms are still inconclusive, and they have been tentatively classified as both algae and protozoa. A representative gene of the mitochondrial genome, cytochrome oxidase subunit I (coxI), was chosen and sequenced to clarify the phylogenetic positions of four dinoflagellates, two euglenophytes and one apicomplexan protist.

Use of a deviant mitochondrial genetic code in yellow-green algae as a landmark for segregating members within the phylum.

Several algae that were previously classified in the phylum Xanthophyta (yellow-green algae) were assigned in 1971 to a new phylum, Eustigmatophyta. It was anticipated that the number of algae reclassified to Eustigmatophyta would increase. However, due to the fact that the morphological characteristics that segregate eustigmatophytes from other closely related algae can be only obtained through laborious electron microscopic techniques, the number of members in this phylum have increased rather slowly.

Morphological features of a filamentous phage of Vibrio cholerae O139 Bengal.

A filamentous phage was isolated from carrier strain AI-1841 of Vibrio cholerae 0139 Bengal and thus was termed fs phage. The phage was measured to be approximately 1 microm in length and 6 nm in width. One end of the phage was slightly tapered and had a fibrous appendage.

A classical strain of Vibrio cholerae with diminished ability to process the proteolytically sensitive site in the A subunit of cholera toxin.

Vibrio cholerae O1, No. 31, a strain isolated from a patient with mild diarrhea, produced mainly the unnicked cholera toxin. The amount of toxin that had accumulated in the cells was approximately 200 times lower than that secreted into the culture medium.

Cloning and sequencing of the gene encoding Vibrio cholerae O1 fimbrial subunit (fimbrillin).

The gene encoding an 18 kDa fimbrial subunit of Vibrio cholerae O1 was identified in a fimbriate strain Bgd17. Mixed oligoprimers were prepared based on the amino acid sequence of the N-terminus and that from a cyanogen bromide-cleaved fragment of the fimbrillin. A PCR-amplified 185 bp DNA fragment was sequenced.

The effect on enterotoxicity of protease purified from Vibrio cholerae O1.

The effect on enterotoxicity of protease purified from Vibrio cholerae O1 was investigated by the inoculation of live vibrio cells into protease-treated loops of the ileal loop model. Fluid accumulation ratios in the protease-treated loops were elevated in a dose-dependent manner by challenge with live vibrio cells but not by that with toxin. An enhancement effect of protease on enterotoxicity was observed in both serotypes of V.

Immunogenicity of Vibrio cholerae O1 fimbriae in animal and human cholera.

Parenteral immunization with either formalin-fixed whole cells of the fimbriate Bgd17 strain or purified fimbriae protected against Vibrio cholerae O1 infection in rabbits, independent of biotype and serotype. Parenteral immunization of adult rabbits with purified fimbriae prior to V. cholerae O1 challenge resulted in a reduction of 2 to 3 orders of magnitude in the number of bacteria recovered from the small intestines of immunized rabbits in comparison to non-immunized controls.

The protease from Vibrio cholerae nicks arginine at position 192 from the N-terminus of the heat-labile enterotoxin a subunit from enterotoxigenic Escherichia coli.

It was examined where a protease purified from Vibrio cholerae might nick the heat-labile enterotoxin (LT) A subunit from enterotoxigenic Escherichia coli. LT was digested by the protease and contained a fragment which had the same mobility on SDS-PAGE as that of the A1 fragment of LT digested by trypsin. The biological activity of LT by this protease was also identical to that of LT by trypsin.

The fimbriae-like structures on V. cholerae isolated in Kenya.

For Vibrio cholerae 01 to overcome the normal intestinal clearing mechanisms and facilitate colonization in the host gut, fine filamentous structures covering the surface of all the cell must exist. These fimbriae-like structures were investigated in this study. Selection of the K23 V.

Studies on novel pili from Shigella flexneri. I. Detection of pili and hemagglutination activity.

Pili were detected using electron microscopy in clinical isolates of Shigella flexneri which had been continuously subcultivated in liquid media. Morphologically, the pili appeared as thin, flexible, cylindrical structures of up to 2-5 microns in length and about 3-5 nm in diameter. Two strains showed mannose-resistant (MR) hemagglutination to fresh fowl erythrocytes (type 4), and one to tannic acid-treated horse erythrocyte (type 3) pili.

Study of enzyme inhibitory activities by dipyridamole.

Inhibitory activities of Dipyridamole (DPM, 2,6-bis(diethanolamino)-4,8-dipiperidinopyrimido(5,4-d)py rim idine) against xanthine oxidase (XO), carbonic anhydorase (CA) and monoamine oxidase (MAO) were studied, in vitro. DPM did not inhibit XO and CA, but it strongly inhibited MAO. The type of inhibition by DPM against MAO with respect to benzylamine as a substrate was uncompetitive.

Diethylcarbamazine, antifilarial drug, inhibits microtubule polymerization and disrupts preformed microtubules.

The effect of diethylcarbamazine (DEC) on microtubules was studied by using microtubule protein prepared from porcine brain. DEC inhibited assembly of microtubules and disassembled preformed microtubules in vitro. When the reassembled or disassembled products were examined in the presence of DEC by electron microscopy, ribbon-microtubules were frequently observed.

Detection of IgA protease from Haemophilus influenzae by immunoblotting.

IgA protease produced by various strains of Haemophilus influenzae can digest serum IgA and yield its fragments which can react with anti-IgA serum. We assayed IgA protease activity by detecting the digests of IgA by SDS-PAGE and immunoblotting. The digests were separated with SDS-PAGE, transferred to nitrocellulose membranes and detected with anti- (alpha chain of human IgA, its Fab and its Fc) immunoglobulin conjugated peroxidases.

Pili of Vibrio cholerae O1 biotype E1 Tor: a comparative study on adhesive and non-adhesive strains.

Pili were found on the cell surface of non-adhesive Vibrio cholerae O1 Biotype E1 Tor as well as the adhesive strain. Purified pili of the adhesive and non-adhesive strains were morphologically, electrophoretically, and immunologically, indistinguishable from each other. The molecular weights of both pilin (subunit protein of the pilus) were about 16,000 daltons as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Purification and partial characterization of fimbriae of Vibrio cholerae O1.

Fimbriae of Vibrio cholerae O1 were purified from a strain of the classical biotype, Inaba serotype (Bgd 17), and a strain of the El Tor biotype, Ogawa serotype (K23), grown on TCG agar medium by the following procedure; homogenization of the cell suspension to detach fimbriae, ultracentrifugation to remove remaining cells and their debris, concentration of the supernatant containing fimbriae with ultrafiltration, and 20 to 40% sucrose linear gradient centrifugation of the concentrated material. The fimbriae in both preparations were flexible, long fibres readily distinguishable under the electron microscope from those of CFA/I, CFA/II seen in ETEC strains. Their structural subunit was a protein of 16 kdaltons.

The characterization of Vibrio cholerae isolated in Kenya in 1983.

A total of 245 strains of Vibrio cholerae 01 and two strains of V. cholerae non-01 were isolated and collected from diarrhoeal patients in Homa Bay District Hospital and the other medical facilities in Nyanza Province, Kenya in 1983. The majority of V.

Serum lipase response to cerulein secretin stimulation test in patients with pancreas-associated diseases as measured by sensitive colorimetric assay (a BALB-DTNB method).

We have compared responsiveness of serum lipase and amylase activity to the pancreatic exocrine stimulation with cerulein and secretin (CS test) in normal subjects and patients with pancreas-related and other diseases. The lipase and amylase activities were measured by a sensitive colorimetric method, the BALB-DTNB method and the Caraway method, respectively. The percentage of positive lipase and amylase response cases was as follows: confirmed chronic pancreatitis (N = 22), 27 and 14%; suspected chronic pancreatitis (N = 37), 46 and 32%; pancreatic cancer (N = 16), 44 and 25%; biliary tract diseases (N = 11), 14 and 14%; miscellaneous (N = 11), 0 and 18%; normal subjects (N = 13), and partial pancreatectomy (N = 5), 0 and 0%, respectively.