Small Colony Variants of Escherichia coli

TLDR: The present report deals with the production of small colony variants of E. coli with 2-methyl-1 ,4-napthoquinone and is believed worth recording because of the frequency of their appearance, the purity of the phase obtained, and their possible significance in regard to the mechanism of the antibacterial action of this quinone.

Abstract: Small colony variants of several species of bacteria have been described (Hadley, Delves, and Klimek, 1931; Hoffstadt and Youmans, 1932; Koser and Dienst, 1934; Duff, 1937; Haddow, 1938; Kuhn and Stemnberg, 1931). Their recovery has usually been a matter of chance, because of their sporadic occurrence, with one exception: Youmans (1937, 1942) has reported the regular appearance of small colony variants in 17 strains of staphylococci in response to barium chloride. References to small colony variants of Escherichia coli are rare. Hadley, Delves, and Klimek (1931) mention briefly that \"G\" forms similar to \"G\" forms of the Shigella group extensively studied by them were recovered from 2 strains of E. coli; and Kuhn and Steinberg (1931) found small colony variants in 45 strains of E. coli, among other organisms. The present report deals with the production of small colony variants of E. coli with 2-methyl-1 ,4-napthoquinone and is believed worth recording because of the frequency of their appearance, the purity of the phase obtained, and their possible significance in regard to the mechanism of the antibacterial action of this quinone.