Formation of disulphide bonds in the reaction of SH group-containing amino acids with trimethylamine N-oxide. A regulatory mechanism in proteins.
Two amino acids containing SH group (cysteine and homocysteine)+trimethylamine N-oxide systems were studied by FTIR and 1H NMR spectroscopy. This study demonstrates that cysteine and homocysteine ethylesters react with trimethylamine N-oxide. Immediately after mixing, SH...ON<==>S-...H+ ON hydrogen bonds with large proton polarizability are are formed. Then a reaction proceeds resulting in the formation of corresponding disulphides. Trimethylamine N-oxide is present in biological systems. Thus, our results suggest that trimethylamine N-oxide may play a regulatory role in S-S bond formation in enzymes and other proteins.
Brzezinski
B
B
Faculty of Chemistry, A. Mickiewicz University, Poznan, Poland.
Zundel
G
G
D003545:Cysteine / Q000737:chemistry*; D004220:Disulfides; D006710:Homocysteine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008744:Methylamines / Q000494:pharmacology; D016877:Oxidants; D011506:Proteins / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
D004220:Disulfides; D008744:Methylamines; D016877:Oxidants; D011506:Proteins; D006710:Homocysteine; C005855:trimethyloxamine; D003545:Cysteine