Sulfuryl transfer catalyzed by pyruvate kinase.
Sulfoenolpyruvate, the analogue of phosphoenolpyruvate in which the phosphate ester has been replaced by a sulfate ester, has been synthesized in three chemical steps from ethyl bromopyruvate in 40% overall yield. This compound is a substrate for pyruvate kinase, producing pyruvate and adenosine 5'-sulfatopyrophosphate. The latter compound has been identified by NMR spectroscopy and by comparison with an authentic sample. Sulfuryl transfer from sulfoenolpyruvate is 250-600-fold slower than phosphate transfer from phosphoenolpyruvate under identical conditions. Sulfoenolpyruvate is not a substrate for phosphoenolpyruvate carboxylase. Kinetic studies reveal that it does not bind to the active site; instead, it binds to the site normally occupied by glucose 6-phosphate and activates the enzyme in a manner similar to that shown by glucose 6-phosphate.
Peliska
J A
JA
Department of Chemistry, University of Wisconsin-Madison 53706.
O'Leary
M H
MH
D000818:Animals; D007700:Kinetics; D007773:Lactates / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009132:Muscles / Q000201:enzymology; D011485:Protein Binding; D011770:Pyruvate Kinase / Q000378:metabolism*; D011773:Pyruvates / Q000138:chemical synthesis / Q000378:metabolism*; D011817:Rabbits; D013055:Spectrophotometry, Infrared / Q000379:methods; D013379:Substrate Specificity
D007773:Lactates; D011773:Pyruvates; C059702:sulfoenolpyruvate; D011770:Pyruvate Kinase