Some Aspects of Biotin Binding to Protein Catalyzed by Biotin-Deficient Chicken Liver Preparations 1

Abstract

Summary

Mitochondrial and cytosolic preparations obtained from biotin-deficient chicken liver catalyze incorporation of ¹⁴C-relabeled D-biotin to protein. The pH optima for the two enzyme systems are different. ATP is required for the reaction. Omission of GSH and MgCl₂ from the reaction mixture does not appreciably affect enzyme activity. Nucleoside triphosphates other than ATP are also effective in promoting biotin binding to protein. High concentrations of AMP as well as ADP inhibit the reaction. Citrate exerts a slight stimulatory effect on the activity of the cytosolic preparation.