title: Control by A-factor of a metalloendopeptidase gene involved in aerial mycelium formation in Streptomyces griseus.
abstract: In Streptomyces griseus, A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. An A-factor-dependent transcriptional activator, AdpA, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. A region upstream of a zinc-containing metalloendopeptidase gene (sgmA) was found among the DNA fragments that had been isolated as AdpA-binding sites. The primary product of sgmA consisted of N-terminal pre, N-terminal pro, mature, and C-terminal pro regions. sgmA was transcribed in an AdpA-dependent manner, and its transcription was markedly enhanced at the timing of aerial mycelium formation. AdpA bound two sites in the region upstream of the sgmA promoter; one was at about nucleotide position -60 (A site) with respect to the transcriptional start point of sgmA, and the other was at about position -260 (B site), as determined by DNase I footprinting. Transcriptional analysis with mutated promoters showed that the A site was essential for the switching on of sgmA transcription and that the B site was necessary for the marked enhancement of transcription at the timing of aerial mycelium formation. Disruption of the chromosomal sgmA gene resulted in a delay in aerial hypha formation by half a day. SgmA is therefore suggested to be associated with the programmed morphological development of Streptomyces, in which this peptidase, perhaps together with other hydrolytic enzymes, plays a role in the degradation of proteins in substrate hyphae for reuse in aerial hypha formation.
authors.affiliation: Department of Biotechnology, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Japan.
authors.forename: Jun-ya
authors.initials: JY
authors.lastname: Kato
authors.forename: Ayano
authors.initials: A
authors.lastname: Suzuki
authors.forename: Haruka
authors.initials: H
authors.lastname: Yamazaki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohnishi
authors.forename: Sueharu
authors.initials: S
authors.lastname: Horinouchi
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular; D018983:DNA Footprinting; D004269:DNA, Bacterial / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003850:Deoxyribonuclease I; D005798:Genes, Bacterial; D008666:Metalloendopeptidases / Q000235:genetics*; D008969:Molecular Sequence Data; D009711:Nucleotides; D010641:Phenotype; D017422:Sequence Analysis, DNA; D013305:Streptomyces griseus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D016335:Zinc Fingers
chemical_list: C401645:AdpA protein, Streptomyces griseus; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D009711:Nucleotides; D015534:Trans-Activators; C025035:A-factor (Streptomyces); D003850:Deoxyribonuclease I; D008666:Metalloendopeptidases; D015107:4-Butyrolactone