4QVG

Crystal structure of S-adenosylmethionine-dependent methyltransferase SibL in its apo form

Summary for 4QVG

• Entry DOI: 10.2210/pdb4qvg/pdb
• Descriptor: SibL (1 entity in total)
• Functional Keywords: methyltransferase, transferase
• Biological source: Streptosporangium sibiricum
• Total number of polymer chains: 4
• Total formula weight: 155695.19

Authors

Liu, J.S.,Chen, S.C.,Huang, C.H.,Yang, C.S.,Chen, Y. (deposition date: 2014-07-15, release date: 2015-05-27, Last modification date: 2023-11-08)

Primary citation

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.
Structure and mechanism of an antibiotics-synthesizing 3-hydroxykynurenine C-methyltransferase
Sci Rep, 5:10100-10100, 2015

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.

PubMed: 25960001
DOI: 10.1038/srep10100

Experimental method

X-RAY DIFFRACTION (2.9 Å)