The use of a spectrophotometric assay to study the interaction of S-adenosylmethionine synthetase with methionine analogues.
We have developed a continuous spectrophotometric assay for S-adenosylmethionine synthetase and, using this assay, have examined the interaction of five potential inhibitors with the E. coli enzyme. S-Vinylhomocysteine and S-allylhomocysteine were found to be substrates, while S-(methanethio)cysteine and S-(methanethio)homocysteine were found to be competitive inhibitors. S-Cyanohomocysteine is neither a substrate nor an inhibitor.
Kim
H J
HJ
Department of Chemistry, Amherst College, Massachusetts 01002.
Balcezak
T J
TJ
Nathin
S J
SJ
McMullen
H F
HF
Hansen
D E
DE
D001426:Bacterial Proteins / Q000032:analysis / Q000037:antagonists & inhibitors*; D001667:Binding, Competitive; D004355:Drug Stability; D004926:Escherichia coli / Q000201:enzymology; D005001:Ethionine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D007700:Kinetics; D008715:Methionine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D008716:Methionine Adenosyltransferase / Q000032:analysis / Q000037:antagonists & inhibitors*; D013053:Spectrophotometry; D013452:Sulfonium Compounds / Q000378:metabolism
D001426:Bacterial Proteins; D013452:Sulfonium Compounds; C020543:vinthionine; D008715:Methionine; D008716:Methionine Adenosyltransferase; D005001:Ethionine