INHIBITORY ACTION OF PHAGE K ON STAPHYLOCOCCAL DEHYDROGENASES. I. EFFECT ON VARIOUS STRAINS OF STAPHYLOCOCCUS AUREUS, INCLUDING MEMBERS OF THE PHAGE-TYPING SERIES.

Ralston, D. J. (University of California, Berkeley) and B. S. Baer. Inhibitory action of phage K on staphylococcal dehydrogenases. I. Effect on various strains of Staphylococcus aureus, including members of the phage-typing series. J. Bacteriol. 86:666-672. 1963.-The polyvalent phage K was found to depress the dehydrogenase activities of a large number of Staphylococcus aureus strains, as measured by the reduction of triphenyl tetrazolium chloride to the insoluble red formazan. The inhibition occurred immediately after the absorption of a multiplicity of phage particles, and was independent of the infectibility of the strains and of the killing ability of the phage. It appeared to be closely associated with the phenomenon of sensitization-a change in the cell surface which increased the susceptibility of the wall to digestion by soluble staphylococcal lysins and simultaneously abolished the capacity to synthesize phage. The inhibitory effect occurred both in nutrient media and in a nongrowth glucose - phosphate buffer supplemented with cysteine.