1p0y
From Proteopedia
Crystal structure of the SET domain of LSMT bound to MeLysine and AdoHcy
Structural highlights
FunctionRBCMT_PEA Methylates 'Lys-14' of the large subunit of RuBisCO. Can also use with lower efficiency chloroplastic fructose-bisphosphate aldolases and gamma-tocopherol methyltransferase as substrates, but not a cytosolic aldolase.[1] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedSET domain protein methyltransferases catalyze the transfer of methyl groups from the cofactor S-adenosylmethionine (AdoMet) to specific lysine residues of protein substrates, such as the N-terminal tails of histones H3 and H4 and the large subunit of the Rubisco holoenzyme complex. The crystal structures of pea Rubisco large subunit methyltransferase (LSMT) in ternary complexes with either lysine or epsilon-N-methyllysine (MeLys) and the product S-adenosylhomocysteine (AdoHcy) were determined to resolutions of 2.65 and 2.55 A, respectively. The zeta-methyl group of MeLys is bound to the enzyme via carbon-oxygen hydrogen bonds that play a key role in catalysis. The methyl donor and acceptor are aligned in a linear geometry for S(N)2 nucleophilic transfer of the methyl group during catalysis. Differences in hydrogen bonding between the MeLys epsilon-amino group and Rubisco LSMT and SET7/9 explain why Rubisco LSMT generates multiply methylated Lys, wheras SET7/9 generates only MeLys. Mechanism of multiple lysine methylation by the SET domain enzyme Rubisco LSMT.,Trievel RC, Flynn EM, Houtz RL, Hurley JH Nat Struct Biol. 2003 Jul;10(7):545-52. PMID:12819771[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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