TY - JOUR
T1 - Rubisco small and large subunit N-methyltransferases. Bi- and mono- functional methyltransferases that methylate the small and large subunits of Rubisco
AU - Ying, Zhentu
AU - Mulligan, R. Michael
AU - Janney, Noel
AU - Houtz, Robert L.
PY - 1999/12/17
Y1 - 1999/12/17
N2 - Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)is methylated at the α-amino group of the N-terminal methionine of the processed form of the small subunit (SS), and at the ε-amino group of lysine-14 of the large subunit (LS) in some species. The Rubisco LS methyltransferase (LSMT) gene has been cloned and expressed from pea and specifically methylates lysine-14 of the LS of Rubisco. We determine here that both pea and tobacco Rubisco LSMT also exhibit (α)N-methyltransferase activity toward the SS of Rubisco, suggesting that a single gene product can produce a bifunctional protein methyltransferase capable of catalyzing both (α)N-methylation of the SS and (ε)N-methylation of the LS. A homologue of the Rubisco LSMT gene (rbcMT-S) has also been identified in spinach that is closely related to Rubisco LSMT sequences from pea and tobacco. Two mRNAs are produced from rbcMT-S, and both long and short forms of the spinach cDNAs were expressed in Escherichia coli cells and shown to catalyze methylation of the α-amino group of the N- terminal methionine of the SS of Rubisco. Thus, the absence of lysine-14 methylation in species like spinach is apparently a consequence of a monofunctional protein methyltransferase incapable of methylating Lys-14, with activity limited to methylation of the SS.
AB - Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)is methylated at the α-amino group of the N-terminal methionine of the processed form of the small subunit (SS), and at the ε-amino group of lysine-14 of the large subunit (LS) in some species. The Rubisco LS methyltransferase (LSMT) gene has been cloned and expressed from pea and specifically methylates lysine-14 of the LS of Rubisco. We determine here that both pea and tobacco Rubisco LSMT also exhibit (α)N-methyltransferase activity toward the SS of Rubisco, suggesting that a single gene product can produce a bifunctional protein methyltransferase capable of catalyzing both (α)N-methylation of the SS and (ε)N-methylation of the LS. A homologue of the Rubisco LSMT gene (rbcMT-S) has also been identified in spinach that is closely related to Rubisco LSMT sequences from pea and tobacco. Two mRNAs are produced from rbcMT-S, and both long and short forms of the spinach cDNAs were expressed in Escherichia coli cells and shown to catalyze methylation of the α-amino group of the N- terminal methionine of the SS of Rubisco. Thus, the absence of lysine-14 methylation in species like spinach is apparently a consequence of a monofunctional protein methyltransferase incapable of methylating Lys-14, with activity limited to methylation of the SS.
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U2 - 10.1074/jbc.274.51.36750
DO - 10.1074/jbc.274.51.36750
M3 - Article
C2 - 10593982
AN - SCOPUS:0033579564
SN - 0021-9258
VL - 274
SP - 36750
EP - 36756
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 51
ER -