STUDIES ON A MECHANISM PROVIDING FOR GENETIC TRANSFER IN SERRATIA MARCESCENS

Publisher Website
Google Scholar
Abstract
A mechanism for genetic transfer in S. marcescens is described and compared to other known genetic processes in bacteria. Cell-free filtrates are incapable of promoting proto-troph formation, and a donor-acceptor relationship exists among the mutants. Differential stimulation by UV light of the frequency of prototroph formation by different parental strains is interpreted as reflecting the heterogeneity of these strains in regard to the proportions of donor and acceptor cells. No streptomycin effect similar to that determining the F-[long dash]F- relationship in Escherichia coli was demonstrable. The transfer seems to involve only small units of genetic material, since acceptor strains with more than one biochemical requirement cannot form prototrophs, while when multiple auxotrophs act as donors there is no decrease in the number of prototrophs.