Showing papers by "Elisabetta Meucci published in 1986"
TL;DR: Aromatic residues of bovine kidney alkaline phosphatase appear to be involved in the interaction with ascorbate, as shown by the strong quenching of intrinsic fluorescence and absorption and attempts to reverse the effects by the use of KOH fail to restore enzyme activity or to modify the spectral effects of asCorbate.
Abstract: Aromatic residues of bovine kidney alkaline phosphatase appear to be involved in the interaction with ascorbate, as shown by the strong quenching of intrinsic fluorescence and absorption. Difference u.v.-absorption spectra clearly indicate that conformational changes also occur. The pH value at which the greatest fluorescence deactivation is found is close to that necessary for optimal catalytic activity and for maximal inhibition by ascorbate. A protective effect against ascorbate is afforded by Pi. Time profiles of inactivation on one side and of absorbance and emission quenching on the other display opposite behaviours. Attempts to reverse the effects by the use of KOH fail to restore enzyme activity or to modify the spectral effects of ascorbate. The protein alterations are related, directly or indirectly, to the enzyme active centre and can be probably ascribed to the redox and chelating properties of ascorbate.
8 citations
01 Jan 1986
TL;DR: In this paper, the HP8450AUV-Visspectrophotometer was used to measure the absorbance of a protein and a modifier against a blank consisting of exactly the same amount of modifier(s) only.
Abstract: bysubtractingtheemissionoftheuntreatedfromthatofthe treated protein.AbsorbancewasmeasuredwithanHP8450AUV-Visspectrophotometer (Hewlett-Packard, Palo Alto, CA,U.S.A.). Measurements were taken well inside thephotometerresponse range, withfinal absorbance neverexceeding 2.5. Absorption spectra were obtained byreading the test cuvettes, containing the protein and afixed amount of the modifier(s), against a blankconsisting ofexactly the sameamountofthemodifier(s)only. Difference spectra were obtained