Agar Electrophoresis of Antibiotics produced by Serratia marcescens

Abstract

INDIVIDUAL strains of Serratia marcescens may liberate two different bacteriocins¹. The distinction is made on grounds of temperature of inactivation and susceptibility to various other destructive agents coupled with distinctive spectra of activity. During an investigation of antibiotics produced by Serratia the foregoing phenomenon was also encountered and electrophoretic separation of the components was attempted. Strains, media and electrophoretic techniques were those previously used^2,3. In addition, twenty strains isolated locally and numbered Sm 16–19 and Sm 37–52 were also investigated. All 51 Serratia strains could be differentiated on grounds of lysogenicity and phage susceptibility Antibiotic activity was detected by the method of Fredericq⁴ or by spotting the clear supernatants of overnight growths of cultures induced by ultra-violet light on plates freshly spread with indicator organisms.