Cell division in a species of Erwinia. V. Effect of metabolic inhibitors on terminal division and composition of a "division" medium

Strain-specific difference that affects the inhibition of division of Escherichia coli filaments by chloramphenicol

The Escherichia coli mutations ts1882 and ts2158 cause temperature-sensitive septum formation and result in growth of cells as long, multinucleate, nonseptate filaments at 42 C. When filaments are transferred to 28 C, they divide into short cells. Chloramphenicol, when added to cultures of filaments at the time of temperature reduction. Inhibited division of filaments when these temperature-sensitive mutations were present in the K-12 strain AB1157. However, when the ts1882 and ts2158 mutations were present in another k-12 strain, UTH4113, filaments of these strains divided in the presence of chloramphenicol.

Control of cell division in bacteria

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Inhibitory effects of mitomycin-related compounds lacking the C1-C2 aziridine ring

Three chemical derivatives of mitomycin C cause loss of viability, inhibition of deoxyribonucleic acid synthesis, and inhibition of cell division in bacteria. Each of these drugs lacks the C(1)-C(2) aziridine ring previously postulated to be essential for the bactericidal effect of mitomycin C.

Filament formation in Clostridium acidiurici under conditions of elevated temperatures

Terry, David R. (Brigham Young University, Provo, Utah), Abdul Gaffar, and Richard D. Sagers. Filament formation in Clostridium acidiurici under conditions of elevated temperatures. J. Bacteriol. 91:1625-1634. 1966.-Vegetative cells of Clostridium acidiurici, when grown at temperatures up to 42 C, are straight rods varying from 2.5 to 4 mu in length. When grown at 43 C, the cells show a definite tendency to elongate, and, when grown at 44 C, filaments are formed, often exceeding 500 mu in length. Only an occasional cross wall is apparent in the heat-induced long forms, but as the temperature is lowered they readily form cross walls and fragment into short, single cells. Chromatin material is distributed in evenly spaced clusters throughout the length of the filaments. The filaments grown at 44 C are gram-negative, whereas cells grown at 37 C are gram-positive. However, filament formation and gram-negativity apparently are not due to magnesium deficiency, since the gram-negative filaments are formed in concentrations of magnesium ranging from 10(-6) to 10(-2)m. The rapid transition from filaments to single cells upon lowering the temperature from 44 to 37 C suggests that the temperature-related repression of the cross wall-forming system is a phenotypic response rather than the selection of specific mutants which produce the observed phenomena.