Comparative study of Vibrio cholerae non-O1 protease and soluble hemagglutinin with those of Vibrio cholerae O1

Abstract

Protease and soluble hemagglutinating activities produced by a non-O1 Vibrio cholerae strain isolated from a patient with diarrhea were compared with similar activities produced by V. cholerae 01. The soluble protease activities were indistinguishable in heat stability, immunodiffusion, inhibition by antiserum, and electrophoretic analysis. On the other hand, the soluble hemagglutinating activities of both strains were not completely identical. The hemagglutinating activity of the non-O1 V. chokrae strain was not inhibited by Zincov; it was more sensitive to inhibition by normal serum, and it had an unusual pattern of heat stability. Heating at 100°C resulted in some recovery of activity of a sample previously inactivated by heating at 600C.

The effect on enterotoxicity of protease purified from Vibrio cholerae O1

“…1). The purified protease was biochemically and physicochemically identical to HA/protease, as previously reported by Booth et al [3] and Honda et al [7]. The hemagglutinin activity of purified protease, however, was not detected as previously reported [15].…”

“…The strains of V. cholerae used in the experiment are listed in Table 1. Protease activity of strains of V. cholerae was checked by a single-diffusion technique in agar gel (0.75%) containing skim milk (1.5%) as a substrate as previously described [7]. A total of 40 strains of V. cholerae were cultured in tryptic soy broth with shaking at 30°C for 20 h. Culture supernatant (20 /zl) obtained after centrifugation (40000 × g, 20 min) was added to wells 3.5 mm in diameter, and the plates were incubated for 12 h at 37°C.…”

Phase variation in tcpH modulates expression of the ToxR regulon in Vibrio cholerae

“…Results presented are representative of at least three independent experiments. Haemagglutinin/protease activity was detected by a minor modification of Blackwell Science Ltd, Molecular Microbiology, 25, 1099-1111 a previously described single-diffusion technique in agar containing 1% skim milk as substrate (Honda et al, 1987).…”

Characterization of non-membrane-damaging cytotoxin of non-toxigenic Vibrio cholerae O1 and its relevance to disease

“…It also nicks and activates CT and CT-related enterotoxins [24]. Besides the protease activity, HA/P also shows hemagglutinating activity [25,26] on erythrocytes of Balb/c mice, but this activity has not been consistently reproduced [27,28]. Our study showed that NMDCY has a protease activity which is inhibited by metal chelators, but has no hemagglutinating activity on Balb/c mice and chicken erythrocytes.…”