Disruption of a gene encoding a putative gamma-butyrolactone-binding protein in Streptomyces tendae affects nikkomycin production.
A 2.6-kb BamHI fragment from the genome of the wild-type, nikkomycin-producing strain of Streptomyces tendae ATCC 31160 was cloned and sequenced. This 2.6-kb BamHI fragment corresponds to the DNA site where transposon Tn4560 had inserted to create a nikkomycin-nonproducing mutant. A possible ORF of 660 nucleotides was found in this 2.6-kb BamHI fragment, in which the third base of each codon was either G or C in 92% of the codons. The deduced amino acid sequence coded by this ORF (TarA, tendae autoregulator receptor) shows strong homology with several Gamma-butyrolactone-binding proteins that negatively regulate antibiotic production in other streptomycetes and have a helix-turn-helix DNA-binding motif. A portion (179 nucleotides) of tarA that encodes the helix-turn-helix motif was replaced with ermE, and wild-type S. tendae was transformed with this construct borne in pDH5, a gene-disruption vector. Southern hybridization indicated that ermE had inserted in the 2.6-kb BamHI region in one isolate that is erythromycin resistant. Northern hybridization indicated that tarA disruption significantly increased the amount of disrupted-tarA mRNA. This suggests that TarA negatively regulates its own synthesis. Nikkomycin production by the tarA disruptant was delayed but reached the wild-type level after longer incubation in production medium.
Engel
P
P
Southern Regional Research Center, USDA, Agricultural Research Service, New Orleans, LA 70179, USA. pengel@commserver.srrc.usda.gov
Scharfenstein
L L
LL
Dyer
J M
JM
Cary
J W
JW
D015107:4-Butyrolactone / Q000378:metabolism*; D000595:Amino Acid Sequence; D000617:Aminoglycosides; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D004251:DNA Transposable Elements / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015245:Deoxyribonuclease BamHI / Q000378:metabolism; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D017422:Sequence Analysis, DNA; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism*
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; C011952:nikkomycin; D015245:Deoxyribonuclease BamHI; D015107:4-Butyrolactone