The effects of sodium perchlorate on rabbit muscle enolase--Spectral characterization of the monomer.

摘要: Incubation of rabbit beta enolase in NaClO4 (< or = O.3 M) results a loss enzymatic activity and striking changes the second-derivative ultraviolet spectrum enolase. HPLC gel filtration shows that dissociation dimeric enzyme is occurring. We have used molecular modelling, fluorescence circular dichroic spectroscopy to examine structural differences between monomeric forms this protein. In dimer, tyrosine residues are non-polar environment; upon dissociation, two them were at dimer interface become exposed. This large spectrum. Both tryptophan emission aromatic region CD indicate there also environment other residues. No perturbations peptide bond observed. propose major effect increase flexibility loops connecting helices strands alpha/beta barrel These loops, which contain about half residues, some active site involved subunit contacts. Increased could disrupt both interactions structure site.