Download MendeleyStructure and mechanism of an antibiotics-synthesizing 3-hydroxykynurenine C-methyltransferase
Chen, S.C., Huang, C.H., Lai, S.J., Liu, J.S., Fu, P.K., Tseng, S.T., Yang, C.S., Lai, M.C., Ko, T.P., Chen, Y.(2015) Sci Rep 5: 10100-10100
- PubMed: 25960001
- DOI: https://doi.org/10.1038/srep10100
- Primary Citation of Related Structures:
4QVG - PubMed Abstract:
Streptosporangium sibiricum SibL catalyzes the methyl transfer from S-adenosylmethionine (SAM) to 3-hydroxykynurenine (3-HK) to produce S-adenosylhomocysteine (SAH) and 3-hydroxy-4-methyl-kynurenine for sibiromycin biosynthesis. Here, we present the crystal structures of apo-form Ss-SibL, Ss-SibL/SAH binary complex and Ss-SibL/SAH/3-HK ternary complex. Ss-SibL is a homodimer. Each subunit comprises a helical N-terminal domain and a Rossmann-fold C-terminal domain. SAM (or SAH) binding alone results in domain movements, suggesting a two-step catalytic cycle. Analyses of the enzyme-ligand interactions and further mutant studies support a mechanism in which Tyr134 serves as the principal base in the transferase reaction of methyl group from SAM to 3-HK.
Organizational Affiliation:
1] Department of Biotechnology, Hungkuang University, Taichung, Taiwan [2] Taiwan Advance Biopharm (TABP), Inc., Xizhi City, New Taipei City, Taiwan.
