Conditions Affecting the Viability of Spheroplasts in Urine

Abstract

Penicillin-induced spheroplasts from Escherichia coli and Proteus vulgaris , which at neutral p H had little resistance to osmotic lysis, retained viability in media of low osmolality at p H 5.0 to 5.5. In the presence of 1,000 IU of penicillin per ml ( p H 5.0) in liquid media, E. coli remained in rod form without conspicuous growth. On hypotonic agar media at p H 5.2 with 1,000 IU of penicillin per ml, the bacteria grew out as L-type colonies. These findings are discussed in relation to penicillin therapy.