Flagellar Changes in Escherichia coli induced by Temperature of the Environment

Abstract

THE effect of change of environmental temperature on the motility of a strain of Escherichia coli, type I (N.C.T.C. 8196) has already been described1. This strain, which appeared to be non-motile when examined after 18-hr. growth at 37° C. in meat extract broth or in the same medium solidified with agar, was found to be motile in the early stages of exponential growth (5 hr. at 37° C.) and after growth for 18 hr. or longer at 20° C. Storage of non-motile cells grown at 37° C. at a lower temperature (20° C.) for 1–2 days led to the recovery of motility by most of the cells in the culture. Cells grown at 20° C. retained motility for several weeks, but lost it rapidly when transferred to the incubator at 37° C.