31P and 1H NMR studies of the effect of the counteracting osmolyte trimethylamine-N-oxide on interactions of urea with ribonuclease A.
31P NMR spectroscopy has been used to show that the activity of RNase A, which is lowered in the presence of urea, can be recovered with trimethylamine-N-oxide (TMAO). A 1:1 ratio of TMAO:urea was sufficient to recover the enzyme activity. (1)H nuclear Overhauser effect spectroscopy NMR studies with RNase A have shown that even at relatively low effective concentrations of TMAO, some modification of the three-dimensional structure of the biomolecule is apparent.
Palmer
H R
HR
Department of Physiology, University of Otago Medical School and the Department of Chemistry, University of Otago, Dunedin 9001, New Zealand.
Bedford
J J
JJ
Leader
J P
JP
Smith
R A
RA
D000818:Animals; D002417:Cattle; D006859:Hydrogen; D008744:Methylamines / Q000494:pharmacology*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D016877:Oxidants / Q000494:pharmacology*; D010758:Phosphorus; D011072:Poly U / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D012259:Ribonuclease, Pancreatic / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism*; D014508:Urea / Q000737:chemistry* / Q000494:pharmacology
D008744:Methylamines; D016877:Oxidants; D011072:Poly U; D010758:Phosphorus; D006859:Hydrogen; D014508:Urea; D012259:Ribonuclease, Pancreatic; C005855:trimethyloxamine