The regulation of microcin B, C and J operons.
Microcins are ribosomally encoded small peptide antibiotics produced by Gram(-) enterobacteria. Microcin production-biosynthesis, maturation and secretion to the medium-is encoded by gene clusters organized in operons. Production of the best known plasmid-encoded microcins (MccB, MccC and MccJ) switches on when cells reach the stationary growth phase. This production is doubly regulated at transcriptional level by (a). the growth phase: microcin operons silent/repressed during exponential growth are induced/derepressed when cells sense nutrient starvation and stop exponential growth, and (b). global bacterial regulators acting as inducers or repressors of operon expression. The role played by these regulators (CRP, EmrR, IHF, H-NS, LRP, OmpR, Sigma-38 and SpoT) in the expression of specific microcin operons is reviewed.
Moreno
Felipe
F
Unidad de Genética Molecular, Hospital Ramón y Cajal, Ctra Colmenar Km 9 1, 28034, Madrid, Spain. fmoreno@hrc.insalud.es
Gónzalez-Pastor
José Eduardo
JE
Baquero
Maria Rosario
MR
Bravo
Daniel
D
D001430:Bacteriocins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D004755:Enterobacteriaceae / Q000235:genetics / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D005809:Genes, Regulator; D017930:Genes, Reporter / Q000502:physiology; D005947:Glucose / Q000378:metabolism; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017422:Sequence Analysis, DNA
D001430:Bacteriocins; D011993:Recombinant Fusion Proteins; C020411:microcin; D005947:Glucose