title: Effect of temperature shifts on extracellular proteinase-specific mRNA pools in Pseudomonas fluorescens B52.
abstract: The influence of a shift in temperature from 20 to 32 degrees C on extracellular proteinase synthesis by Pseudomonas fluorescens B52 was examined. When cells actively synthesizing proteinase at 20 degrees C were shifted to 32 degrees C, enzyme synthesis ceased immediately. After 30 min at 32 degrees C, cells recovered at 20 degrees C after a lag of 30 min. Rifampin and chloramphenicol prevented recovery of synthesis at 20 degrees C. Rifampin-insensitive proteinase synthesis (an indirect measure of proteinase-specific mRNA pools) decreased after the exposure of cells to 32 degrees C for 30 min but was recovered during incubation at 20 degrees C. Controls not exposed to a temperature shift experienced no loss of rifampin-independent synthesis. Cells experienced a 50% reduction in mRNA pools after 15 min at 32 degrees C. The data support the working hypothesis that the loss of mRNA pools after treatment at 32 degrees C is responsible for the lag before the recovery of extracellular proteinase synthesis.
mesh_terms: D002701:Chloramphenicol / Q000494:pharmacology; D010450:Endopeptidases / Q000096:biosynthesis* / Q000235:genetics; D007700:Kinetics; D011551:Pseudomonas fluorescens / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D012293:Rifampin / Q000494:pharmacology; D013696:Temperature
chemical_list: D012329:RNA, Bacterial; D012333:RNA, Messenger; D002701:Chloramphenicol; D010450:Endopeptidases; D012293:Rifampin