The rapid inactivation of 3-HBA-6-hydroxylase by 100 microM diethylpyrocarbonate or 40 microM N-bromosuccinimide and protection offered by the substrate, 3-hydroxybenzoate, against these chemical modifications implicate the involvement of histidine and tryptophan in the catalytic activity of the enzyme. Inactivation of the enzyme by diethylpyrocarbonate followed pseudo-first-order kinetics, and...

The tryptophan content of Clostridium perfringens epsilon toxin was investigated. When the tryptophan content was determined by amino acid analysis after the hydrolysis of epsilon prototoxin with methanesulfonic acid containing 3-(2-aminoethyl)indole and by the spectrophotometric method with N-bromosuccinimide, the number of tryptophan residues was calculated at 1/mol of the protein. Cleavage o...

In a previous publication from this laboratory, a method was described for the quantitative bromodecarboxylation of amino acids, proteins, and peptides (1). A review of decarboxylating compounds and of the theories pertinent to their mode of action has been presented by Schijnberg and Moubacher (2). The reaction of N-bromosuccinimide with various compounds in organic solvents has received consi...

The mechanism of specific interaction between a protein and a nucleic acid is thought to reside partially in the arrangement and types of amino acid present in the protein. Attempts have been made to assign specific roles in this interaction to certain amino acids, for example, tryptophan and tyrosine are thought to be involved in unwinding the double helix of DNA (Brun et al., 1975), and in se...