Purification and some properties of exotoxin from Corynebacterium ulcerans strain ATCC 9015

Production of diphtheria toxin by selected isolates of Corynebacterium ulcerans and Corynebacterium pseudotuberculosis

“…Thus, all the C. ulcerans isolates and the C. pseudotuberculosis isolate produced a protein similar in size, immunological structure, enzymatic activity, and substrate specificity to DT. The failure of other investigators (1,18,19) to detect DT production by the C. ulcerans strains is unexplained but might have been due to excess iron in the growth medium.…”

“…In 1974, Souckova and Soucek (17) reported that C. ulcerans ATCC 9015 produced a lethal toxin that caused pathology similar to that caused by DT but was not neutralized by diphtheria antitoxin (anti-DT). Vertiev et al (18,19) went on to report that the toxic moiety was a 40-kilodalton (kd) protein immunologically unrelated to DT and that a nontoxic antigen of 84 kd producing a line of precipitation with anti-DT exhibited no identity with DT. In a second interesting report, Abrehem and Zamiri (1) observed that their isolates of C. ulcerans 378 produced a lethal, toxic protein of 13 to 15 kd which caused pathological changes similar to DT and was neutralized by anti-DT.…”

“…Thus, our tests show that they are genotypically tox+ and phenotypically DT positive. As is apparent from the work of Vertiev et al (18,19), the key to determining the DT phenotype of an organism by in vitro methods is the "purity" of the antitoxin (anti-DT) employed. In the present study, we used a goat anti-DT generously supplied by R. K. Holmes, Uniformed Services University of the Health Sciences, Bethesda, Md.…”