Studies of septation and separation in a mutant of Salmonella typhimurium

✍ Scribed by Dr. N. Ahmed; R. J. Rowbury

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 545 KB
• Volume: 14
• Category: Article
• ISSN: 0233-111X
• DOI: 10.1002/jobm.19740140602

✦ Synopsis

Abstract

Salmonella typhimurium strain 4a is a temperature‐sensitive division mutant. At 39° or 42° in several media a septation lesion occurs since non‐septate filaments form at these temperatures. At lower temperatures in some media separation is aberrant since long chains of cells are formed. Since these division abnormalities are corrected either by revertion to ts^+^ or phenotypically by growth with sucrose, it is likely that both are the result of one lesion and that the component (S) which is temperature‐sensitive in strain 4a is involved in both septation and separation. At 42° S is irreversibly inactivated but at 39° inactivation appears to be reversible since division restarts rapidly when 39° filaments are returned to 25° and protein synthesis is not required for such division. Comparison of recovery times for 39° and 42° filaments suggests that the synthesis of enough S for division takes about 20 min at 25° while the septation and separation stages of division take only about 10 min at this temperature. Since these latter processes occur so quickly it seems likely that events other than septation and separation take up a substantial fraction of the D period.