Characterization of Polysaccharide Accumulations in a Cell Division Defective Mutant of Escherichia coli 15T-

Abstract
E. coli 15T-R1, a temperature-dependent cell division mutant of E. coli 15T-, grows into filaments of various lengths (200-500 .mu.m) at 24.degree. C, but divides essentially normally at 37.degree. C. When grown to late-exponential phase at the restrictive temperature, the elongated cells showed discrete areas of increased density at polar regions and other sites in the cytoplasm, when viewed by phase contrast microscopy. EM of preparations specifically stained for polysaccharide revealed clusters of granules with a similar distribution pattern to that of the dense areas seen by phase contrast microscopy. The granules were susceptible to .alpha.-amylase digestion, and chemical analysis of the extracted and purified polysaccharide showed that it consisted of polyglucose, including glycogen. At 24.degree. C the R1 cells contained about twice as much polyglucose and 4 times as much glycogen as at 37.degree. C.