A microbial hormone, A-factor, as a master switch for morphological differentiation and secondary metabolism in streptomyces griseus

2002 ◽  
Vol 7 (1-3) ◽  
pp. d2045 ◽  
Author(s):  
Sueharu Horinouchi
2019 ◽  
Vol 85 (7) ◽  
Author(s):  
Xu-Liang Bu ◽  
Jing-Yi Weng ◽  
Bei-Bei He ◽  
Min-Juan Xu ◽  
Jun Xu

ABSTRACTThe pleiotropic transcriptional regulator AdpA positively controls morphological differentiation and regulates secondary metabolism in mostStreptomycesspecies.Streptomyces xiamenensis318 has a linear chromosome 5.96 Mb in size. How AdpA affects secondary metabolism and morphological differentiation in such a naturally minimized genomic background is unknown. Here, we demonstrated that AdpASx, an AdpA orthologue inS. xiamenensis, negatively regulates cell growth and sporulation and bidirectionally regulates the biosynthesis of xiamenmycin and polycyclic tetramate macrolactams (PTMs) inS. xiamenensis318. Overexpression of theadpASxgene inS. xiamenensis318 had negative effects on morphological differentiation and resulted in reduced transcription of putativessgA,ftsZ,ftsH,amfC,whiB,wblA1,wblA2,wblE, and a gene encoding sporulation-associated protein (sxim_29740), whereas the transcription of putativebldDandbldAgenes was upregulated. Overexpression ofadpASxled to significantly enhanced production of xiamenmycin but had detrimental effects on the production of PTMs. As expected, the transcriptional level of theximgene cluster was upregulated, whereas the PTM gene cluster was downregulated. Moreover, AdpASxnegatively regulated the transcription of its own gene. Electrophoretic mobility shift assays revealed that AdpASxcan bind the promoter regions of structural genes of both theximand PTM gene clusters as well as to the promoter regions of genes potentially involved in the cell growth and differentiation ofS. xiamenensis318. We report that an AdpA homologue has negative effects on morphological differentiation inS. xiamenensis318, a finding confirmed when AdpASxwas introduced into the heterologous hostStreptomyces lividansTK24.IMPORTANCEAdpA is a key regulator of secondary metabolism and morphological differentiation inStreptomycesspecies. However, AdpA had not been reported to negatively regulate morphological differentiation. Here, we characterized the regulatory role of AdpASxinStreptomyces xiamenensis318, which has a naturally streamlined genome. In this strain, AdpASxnegatively regulated cell growth and morphological differentiation by directly controlling genes associated with these functions. AdpASxalso bidirectionally controlled the biosynthesis of xiamenmycin and PTMs by directly regulating their gene clusters rather than through other regulators. Our findings provide additional evidence for the versatility of AdpA in regulating morphological differentiation and secondary metabolism inStreptomyces.


2011 ◽  
Vol 193 (22) ◽  
pp. 6358-6365 ◽  
Author(s):  
Marcin Wolański ◽  
Rafał Donczew ◽  
Agnieszka Kois-Ostrowska ◽  
Paweł Masiewicz ◽  
Dagmara Jakimowicz ◽  
...  

AdpA is a key regulator of morphological differentiation inStreptomyces. In contrast toStreptomyces griseus, relatively little is known about AdpA protein functions inStreptomyces coelicolor. Here, we report for the first time the translation accumulation profile of theS. coelicoloradpA(adpASc) gene; the level ofS. coelicolorAdpA (AdpASc) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hours (48 to 60 h), and then the signal intensity decreased considerably. AdpAScspecifically binds theadpAScpromoter regionin vitroandin vivo, suggesting that its expression is autoregulated; surprisingly, in contrast toS. griseus, the protein presumably acts as a transcriptional activator. We also demonstrate a direct influence of AdpAScon the expression of several genes whose products play key roles in the differentiation ofS. coelicolor: STI, a protease inhibitor; RamR, an atypical response regulator that itself activates expression of the genes for a small modified peptide that is required for aerial growth; and ClpP1, an ATP-dependent protease. The diverse influence of AdpAScprotein on the expression of the analyzed genes presumably results mainly from different affinities of AdpAScprotein to individual promoters.


Microbiology ◽  
2003 ◽  
Vol 149 (8) ◽  
pp. 1991-2004 ◽  
Author(s):  
Liru Wang ◽  
Leo C. Vining

Three new genes (jadW 1, jadW 2 and jadW 3) were isolated from a region of the Streptomyces venezuelae ISP5230 chromosome at the left-hand end of the jad cluster for jadomycin B (JdB) biosynthesis. The deduced amino acid sequence of jadW 1 showed strong similarity to gene products associated in several streptomycetes with γ-butyrolactone autoregulators controlling morphological differentiation and secondary metabolism. Examination of JadW1 for conserved domains detected a repeat sequence characteristic of proteins in the AfsA regulatory family. Insertional inactivation of jadW 1 reduced the growth rate of S. venezuelae cultures in aerated liquid media containing complex nitrogen sources and altered growth morphology in minimal medium. It also affected sporulation on agar media. Cultures of jadW 1-disrupted mutants grown under conditions supporting biosynthesis of JdB or chloramphenicol by the wild-type strain failed to produce either of the antibiotics. Complementing the disrupted strain by transformation with pJV435, containing a cloned copy of the gene, improved sporulation and restored antibiotic biosynthesis in transformants to titres close to those of the wild-type similarly transformed with pJV435 as a control. The results are consistent with a role for jadW 1 in regulating morphological and metabolic differentiation. Further sequence analysis of jadR 2, which functions with jadR 1 in stress-induced activation of JdB biosynthesis, indicated that this gene encodes a γ-butyrolactone receptor homologue. The growth-rate-sensitive phenotype of the jadW 1-disrupted mutant, and the proximity of jadW 1 to jadR 2 indicate that this region of the jad gene cluster contains a regulatory mechanism incorporating γ-butyrolactone signalling and sensitivity to environmental stress.


2014 ◽  
Vol 70 (a1) ◽  
pp. C214-C214
Author(s):  
Jun Ohtsuka ◽  
Ming Dong Yao ◽  
Koji Nagata ◽  
Ken-ichi Miyazono ◽  
Yuehua Zhi ◽  
...  

AdpA is the central transcriptional factor in the A-factor regulatory cascade of Streptomyces griseus and activates hundreds of genes required for both secondary metabolism and morphological differentiation, leading to onset of streptomycin biosynthesis as well as aerial mycelium formation and sporulation. It has been shown that AdpA binds to over 500 operator regions with the loosely conserved consensus sequence, 5'-TGGCSNGWWY-3' (S: G or C; W: A or T; Y: T or C; and N: any nucleotide). However, it is still obscure how AdpA can control hundreds of genes. To reveal the molecular basis of the low nucleotide sequence specificity, we have determined the crystal structure of the complex of DNA-binding domain of AdpA and a 14-mer duplex DNA with two-nucleotide overhangs at 5'-ends at 2.95-Å resolution. The crystal structure and electrophoretic mobility-shift assays showed that only two arginine residues, Arg262 and Arg266, are involved in the sequence recognition and determine the nucleotide specificity/preference of continuous five base-pairs of positions 1–5 in the consensus sequence. These results partially explain how AdpA directly controls hundreds of genes.


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