Regulatory mutants and transcriptional control of the Serratia marcescens extracellular nuclease gene.
The extracellular nuclease of Serratia marcescens is regulated in a complex fashion. Unlike most catabolic enzymes, it appears not to be substrate regulated. However we have shown it to be regulated by an SOS-like system in S. marcescens. Additionally nuclease expression is regulated in a growth-phase-dependent manner. In this work we demonstrate that growth-phase-dependent regulation is at the transcriptional level. The putative LexA-binding site which mediates SOS regulation is shown to act as an operator site in vivo. The boundaries of a minimal promoter, still regulated by growth phase and SOS regulation, are defined along with the transcriptional start site. However, a region upstream of the nuclease promoter is shown to enhance significantly the expression of nuclease.
Department of Biochemical and Biophysical Sciences, University of Houston, Texas 77204-5934.
Y C
YC
Chen
G L
GL
Shipley
T K
TK
Ball
M J
MJ
Benedik
D000595:Amino Acid Sequence; D001483:Base Sequence; D002453:Cell Cycle; D002874:Chromosome Mapping; D004269:DNA, Bacterial; D004706:Endodeoxyribonucleases; D004720:Endonucleases / Q000235:genetics* / Q000378:metabolism; D004722:Endoribonucleases; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000302:isolation & purification; D012045:Regulatory Sequences, Nucleic Acid; D013014:SOS Response, Genetics; D012706:Serratia marcescens / Q000235:genetics* / Q000254:growth & development; D014158:Transcription, Genetic
D004269:DNA, Bacterial; D012329:RNA, Bacterial; D004706:Endodeoxyribonucleases; D004720:Endonucleases; D004722:Endoribonucleases; C021835:Serratia marcescens nuclease