The A-factor regulatory cascade and cAMP in the regulation of physiological and morphological development in Streptomyces griseus

Citation
S. Horinouchi et al., The A-factor regulatory cascade and cAMP in the regulation of physiological and morphological development in Streptomyces griseus, J IND MIC B, 27(3), 2001, pp. 177-182
Citations number
34
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biotecnology & Applied Microbiology",Microbiology
Journal title
JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY
ISSN journal
1367-5435 → ACNP
Volume
27
Issue
3
Year of publication
2001
Pages
177 - 182
Database
ISI
SICI code
1367-5435(200109)27:3<177:TARCAC>2.0.ZU;2-9
Abstract
In the A-factor regulatory cascade leading to the onset of streptomycin bio synthesis and aerial mycelium formation in Streptomyces griseus, the A-fact or receptor protein (ArpA) serves as a DNA-binding repressor and A-factor r eleases the repression by binding to ArpA and dissociating it from the DNA. Mutants defective in arpA therefore produce streptomycin and aerial hyphae in the absence of A-factor. A gene that inhibits streptomycin production a nd aerial hyphae formation in an arpA mutant was cloned on a high-copy-numb er plasmid and found to encode a eukaryotic-type adenylate cyclase (CyaA). Consistent with this, an exogenous supply of cAMP at high concentration alm ost abolished streptomycin production and aerial hyphae formation. On the o ther hand, cAMP at lower concentrations stimulated or accelerated these dev elopmental processes. The effects of cAMP were detectable only in arpA muta nts, nd not in the wild-type strain; an exogenous supply of cAMP or cyaA di sruption in the wild-type strain caused almost no effect on these phenotype s. Thus the effects of cAMP became apparent only in the arpA-defective back ground. cAMP at high concentrations inhibited stringent response factor ppG pp production, which is important for the onset of antibiotic biosynthesis. cAMP also influenced the timing of tyrosine phosphorylation of more than n ine proteins. These findings show that a cAMP regulatory relay for physiolo gical and morphological development functions in a concerted and interdepen dent way with other signal transduction pathways.