A 4.6 kb DNA fragment was cloned from the DNA library of Streptomyces ansochromogenes using a partial DNA fragment located in the downstream of promoter-PTH4 as probe. The experiments revealed that this DNA fragment c...A 4.6 kb DNA fragment was cloned from the DNA library of Streptomyces ansochromogenes using a partial DNA fragment located in the downstream of promoter-PTH4 as probe. The experiments revealed that this DNA fragment consists of sawD gene and a 1.4 kb Pvu II fragment which can accelerate mycelium formation of S. ansochromogenes. The nucleotide sequence of 1.4 kb DNA fragment was determined and analysed; the result indicated that the fragment contains one complete open reading frame (ORF) which encodes a protein with 213 amino acids, and this gene was designated as samfR. The deduced protein has 36% amino acid identities and 52% amino acid similarities in comparison with that encoded by hppR gene, which is involved in the regulation of catabolism for 3-(3-hydroxyphenyl) propionate (3HPP) in Rhodococcus gtoberulus . The function of samfR gene was studied using strategy of gene disruption, and the resulting samfR mutant failed to form aerial hyphae and spores, its development and differentiation stopped at the stage of substrate mycelium in contrast with wild type strain. The results showed that the samfR gene is closely related to S. ansochromogenes differentiation.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 39830010).
文摘A 4.6 kb DNA fragment was cloned from the DNA library of Streptomyces ansochromogenes using a partial DNA fragment located in the downstream of promoter-PTH4 as probe. The experiments revealed that this DNA fragment consists of sawD gene and a 1.4 kb Pvu II fragment which can accelerate mycelium formation of S. ansochromogenes. The nucleotide sequence of 1.4 kb DNA fragment was determined and analysed; the result indicated that the fragment contains one complete open reading frame (ORF) which encodes a protein with 213 amino acids, and this gene was designated as samfR. The deduced protein has 36% amino acid identities and 52% amino acid similarities in comparison with that encoded by hppR gene, which is involved in the regulation of catabolism for 3-(3-hydroxyphenyl) propionate (3HPP) in Rhodococcus gtoberulus . The function of samfR gene was studied using strategy of gene disruption, and the resulting samfR mutant failed to form aerial hyphae and spores, its development and differentiation stopped at the stage of substrate mycelium in contrast with wild type strain. The results showed that the samfR gene is closely related to S. ansochromogenes differentiation.
