Identification and characterization of the afsR homologue regulatory gene from Streptomyces peucetius ATCC 27952.
We have isolated an afsR homologue, called afsR-p, through genome analysis of Streptomyces peucetius ATCC 27952. AfsR-p shares 60% sequence identity with AfsR from Streptomyces coelicolor A3 (2). afsR-p was expressed under the control of the ermE* promoter in its hosts S. peucetius, Streptomyces lividans TK 24, Streptomyces clavuligerus and Streptomyces griseus. We observed overproduction of doxorubicin (4-fold) in S. peucetius, gamma-actinorhodin (2.6-fold) in S. lividans, clavulanic acid (1.5-fold) in S. clavuligerus and streptomycin (slight) in S. griseus. Overproduction was due to expression of the gene in these strains as compared to the wild-type strains harboring the vector only. Comparative study of the expression of afsR-p revealed that regulatory networking in Streptomyces is not uniform. We speculate that phosphorylated AfsR-p becomes bound to the promoter region of afsS. The latter activates other regulatory genes, including pathway regulatory genes, and induces the production of secondary metabolites including antibiotics. We identified specific conserved amino acids and exploited them for the isolation of the partial sequence of the afsR homologue from S. clavuligerus and Streptomyces achromogens (rubradirin producer). Such findings provide additional evidence for the presence of a serine/threonine and tyrosine kinase-dependent global regulatory network in Streptomyces.
Parajuli
Niranjan
N
Institute of Biomolecule Reconstruction, Sun Moon University, 100 Kalsan-ri, Tangjeonmyun, Asansi, Chungnam 336-708, Republic of Korea.
Viet
Hung Trinh
HT
Ishida
Kenji
K
Tong
Hang Thi
HT
Lee
Hei Chan
HC
Liou
Kwangkyoung
K
Sohng
Jae Kyung
JK
D000595:Amino Acid Sequence; D000880:Anthraquinones / Q000032:analysis; D001426:Bacterial Proteins / Q000235:genetics; D019818:Clavulanic Acid / Q000032:analysis; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D004317:Doxorubicin / Q000032:analysis; D015870:Gene Expression; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D007783:Lactones / Q000032:analysis; D008780:Methyltransferases / Q000235:genetics; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013302:Streptomyces / Q000235:genetics*; D013307:Streptomycin / Q000032:analysis; D014157:Transcription Factors / Q000235:genetics*; D000095622:Benzoisochromanequinones
D000880:Anthraquinones; D001426:Bacterial Proteins; D019818:Clavulanic Acid; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D004317:Doxorubicin; D007783:Lactones; D008780:Methyltransferases; D013307:Streptomycin; D014157:Transcription Factors; C098846:gamma-actinorhodin; D000095622:Benzoisochromanequinones; C035181:rRNA (adenosine-O-2'-)methyltransferase