Reaction of histidine with the biuret reagent in the presence of oxygen

✍ Scribed by Stuart S. Updike; Alexander L. Dounce

• Publisher: Elsevier Science
• Year: 1963
• Tongue: English
• Weight: 702 KB
• Volume: 6
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(63)90002-2

✦ Synopsis

The work outlined in this paper began as an attempted attack on the problem of protein biosynthesis.

A system was constructed consisting of RNA, linear polyphosphate, and a complete amino acid mixture, the biur& reaction being used as an indication of peptide bond formation (1,2). However, it was finally found that only the amino acids histidine and cysteine were necessary for the production of a positive biuret test, the RNA and polyphosphate apparently acting only as modifiers. Attempts to isolate peptide material from the reaction system failed.

This paper summarizes t.he results of work on the nature of the histidine-cysteine-biuret reaction. It has been found that oxygen is a prerequisite for the reaction, and that cysteine acts as a nonspecific reducing agent. Under certain conditions even the reducing agent can be dispensed with, demonstrating that only histidine, copper, and oxygen are the essential ingredients. As far as we are able to determine, t,his reaction was not previously known.