Effect of increased dosage of the ML-236B (compactin) biosynthetic gene cluster on ML-236B production in Penicillium citrinum.
The gene cluster responsible for ML-236B (compactin) biosynthesis has recently been characterized from P. citrinum No. 41520. Here, we describe how the ML-236B-producing strain was improved using a cosmid-mediated recombination technique. The introduction of the cosmid pML48, which contains seven of the nine ML-236B biosynthetic genes, into P. citrinum No. 41520 resulted in transformants which produced increased amounts of ML-236B. Southern analysis showed that pML48 had been incorporated by a homologous recombination event, and all high producers possessed two copies of each of the seven genes, mlcA- mlcF and mlcR, suggesting that increased dosage of the biosynthetic gene cluster was responsible for the enhanced production of ML-236B. On the other hand, various kinds of mutants with decreased titers of ML-236B were also obtained. Characterization of one such mutant, designated as T48.28, which was more sensitive to ML-236B than the parental strain, suggested that one of the ML-236B biosynthetic genes, mlcD, which encodes a putative HMG-CoA reductase, was involved in conferring resistance to ML-236B.
Abe
Y
Y
Lead Discovery Research Laboratories, Sankyo Co. Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan. abyuuk@shina.sankyo.co.jp
Suzuki
T
T
Mizuno
T
T
Ono
C
C
Iwamoto
K
K
Hosobuchi
M
M
Yoshikawa
H
H
D001483:Base Sequence; D002455:Cell Division; D002874:Chromosome Mapping; D004875:Ergosterol / Q000378:metabolism; D018628:Gene Dosage; D005800:Genes, Fungal / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D008148:Lovastatin / Q000031:analogs & derivatives* / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D009154:Mutation; D010407:Penicillium / Q000235:genetics* / Q000378:metabolism*; D013997:Time Factors; D014170:Transformation, Genetic
C012258:mevastatin; D008148:Lovastatin; D004875:Ergosterol