Isolation and purification of Aeromonas sobria cytotonic enterotoxin and beta-haemolysin.
Aeromonas sp., grown in tryptone soya broth supplemented with yeast extract, 0.6%, pH 7.5, and incubated with agitation at 100 oscillations/min for 15 h at 37 degrees C produced optimal amounts of beta-haemolysin and cytotonic enterotoxin. More prolonged incubation resulted in the loss of enterotoxic activity and anion exchange chromatographic analysis indicated the presence of a moiety capable of breaking down the toxin. Anion exchange fast protein liquid chromatography resulted in a single peak of haemolytic activity and two peaks with enterotoxic activity. The cytotonic enterotoxin was purified from the fraction most active in the infant mouse assay; the second peak, which did not cross-react immunologically, may represent a second cytotonic enterotoxin. Neither peak was observed in the chromatographic fractions of filtrates from strains devoid of activity in the infant mouse assay. Purified enterotoxin, estimated to have a mol. wt of 15 kDa by SDS-PAGE, caused fluid accumulation in the infant mouse assay, was non-haemolytic to rabbit erythrocytes, caused an increase in cAMP activity in tissue culture cells and did not cross-react immunologically with components of cholera toxin or the whole toxin. Purified beta-haemolysin had an estimated mol. wt of 55 kDa, lysed rabbit erythrocytes and did not cause fluid accumulation in the infant mouse test.
Public Health Laboratory, Musgrove Park Hospital, Taunton, Somerset.
P J
PJ
Gosling
P C
PC
Turnbull
N F
NF
Lightfoot
J V
JV
Pether
R J
RJ
Lewis
D000333:Aeromonas / Q000378:metabolism / Q000472:pathogenicity*; D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D002478:Cells, Cultured; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003429:Cross Reactions; D000242:Cyclic AMP / Q000032:analysis / Q000096:biosynthesis; D004591:Electrophoresis, Polyacrylamide Gel; D004768:Enterotoxins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D005677:G(M1) Ganglioside / Q000378:metabolism; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D051379:Mice; D008970:Molecular Weight; D013997:Time Factors; D014774:Virulence / Q000502:physiology
D001427:Bacterial Toxins; D004768:Enterotoxins; D006460:Hemolysin Proteins; D005677:G(M1) Ganglioside; D000242:Cyclic AMP