title: 31P and 1H NMR studies of the effect of the counteracting osmolyte trimethylamine-N-oxide on interactions of urea with ribonuclease A.
abstract: 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.
authors.affiliation: Department of Physiology, University of Otago Medical School and the Department of Chemistry, University of Otago, Dunedin 9001, New Zealand.
authors.forename: H R
authors.initials: HR
authors.lastname: Palmer
authors.forename: J J
authors.initials: JJ
authors.lastname: Bedford
authors.forename: J P
authors.initials: JP
authors.lastname: Leader
authors.forename: R A
authors.initials: RA
authors.lastname: Smith
mesh_terms: 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
chemical_list: D008744:Methylamines; D016877:Oxidants; D011072:Poly U; D010758:Phosphorus; D006859:Hydrogen; D014508:Urea; D012259:Ribonuclease, Pancreatic; C005855:trimethyloxamine