摘要
Cultivation shift from 30℃ to 37℃ significantly enhanced validamycin (VAL) production. Analyzed by reverse-transcription PCR, the transcription of three val genes, valA, valK and valG, representing the three operons of the cluster was simultaneously increased at elevated temperature. Furthermore, the transcription of valP and valQ, a pair of two-component regulators in validamycin biosynthetic gene cluster, was also increased at 37℃. Inactivation of valP and valQ reduced validamycin production at 37℃ to the yield level of wild type strain at 30℃, and the val genes showed reduced expression in the mutant LL-8 at 37℃. These results revealed that the two-component regulator valP and valQ contribute to the elevated validamycin production.
Cultivation shift from 30℃ to 37℃ significantly enhanced validamycin （VAL） production. Analyzed by reverse-transcription PCR, the transcription of three val genes, valA, vaiK and valG, representing the three operons of the cluster was simultaneously increased at elevated temperature. Furthermore, the transcription of valP and valQ, a pair of two-component regulators in validamycin biosynthetic gene cluster, was also increased at 37℃. Inactivation of valP and valQ reduced validamycin production at 37℃ to the yield level of wild type strain at 30℃, and the valgenes showed reduced expression in the mutant LL-8 at 37℃. These results revealed that the two-component regulator valP and valQ contribute to the elevated validamycin production.
基金
Supported by National Key Basic Research and Development Program of China (Grant No. 2003CB114205)
National High Technology Research and Development Program of China (Grant No. 2006AA02Z185)
the National Natural Science Foundation of China (Grant No. 30570019)
the Shanghai Municipal Council of Science and Technology, and Shanghai Leading Academic Discipline Project B203
