- Volume 96, Issue 2, 1976

SUMMARY: The effect of hydrogen peroxide on the germination, colony formation and structure of spores of Clostridium bifermentans was examined. Treatment with 0·35 M-hydrogen peroxide increased the germination rate at 25° but increasing the temperature or concentration of hydrogen peroxide decreased both the germination rate and colony formation. The presence of Cu2+ increased the lethal effect of hydrogen peroxide on colony formation as much as 3000-fold. Pre-incubation of spores with Cu2+ before treatment with hydrogen peroxide produced a similar increase, but this could be eliminated by washing the spores with dilute acid or ethylenediamine tetraacetate. Hydrogen peroxide removed protein from spores—apparently from the coat—and treatment with dithiothreitol, which also removes spore-coat protein, increased the lethal effect of hydrogen peroxide 500-fold, suggesting that spore-coat protein has a protective effect against hydrogen peroxide.

SUMMARY: Acid methanolysates of strains representing 58 coryneform taxa were examined for mycolic acids and other long-chain constituents by thin-layer chromatography. Mycolic esters were detected in the methanolysates of true corynebacteria but not in those from plant pathogenic bacteria, Corynebacterium haemolyticum, Corynebacterium pyogenes or from representatives of the genera Arthrobacter, Cellulomonas, Curtobacterium, Kurthia or Oerskovia. Thin-layer chromatography of whole-organism methanolysates provides a simple method for distinguishing true corynebacteria from coryneforms which do not contain mycolic acids, and from nocardiae and mycobacteria which produce mycolic acids of different mobility. At present the mycolic esters of true corynebacteria cannot be clearly separated from those of some rhodochrous strains.