Expression, purification, and characterization of AknX anthrone oxygenase, which is involved in aklavinone biosynthesis in Streptomyces galilaeus.

ABSTRACT: In streptomycete anthracycline biosynthetic gene clusters, small open reading frames are located just upstream of minimal polyketide synthase genes. aknX is such a gene found in the aklavinone-aclacinomycin biosynthetic gene cluster of Streptomyces galilaeus. In order to identify its function, the aknX gene was expressed in Escherichia coli. The cell extract prepared from E. coli cells overexpressing AknX protein exhibited anthrone oxygenase activity, which converted emodinanthrone to anthraquinone emodin. This indicates that AknX and related gene products such as DnrG and SnoaB are involved in the formation of aklanonic acid from its anthrone precursor, as suggested by their homology with TcmH and ActVA6. The AknX protein fused with a His(6) tag was efficiently purified to homogeneity by

SUBMITTER: Chung JY 

PROVIDER: S-EPMC151955 | biostudies-literature | 2002 Nov

REPOSITORIES: biostudies-literature