UBC Theses and Dissertations
A study of unknown sulfur containing components of proteins Black, F. L.
A review is made of the biochemistry of sulfur and of imidazoles. The results obtained by various workers on the fractional analysis of sulfur in proteins haye been compiled and the possibility that a portion of the protein sulfur at present unaccounted for in certain proteins may be ascribed to the presence of thiolimidazoles has been critically examined. The study suggests that many of the cystine determinations recorded in the literature may be high due to the interference of thiolimidazole breakdown products. A review of the chemistry of the thiolimidazoles is presented and the origin of the recent revival of interest in these compounds discussed. A method has been developed whereby it is possible to separate added ergothioneine from those fractions of a protein hydrolysate that interfere with the Hunter diazo test. It has also been found that this betaine is destroyed by boiling with hydrochloric acid and with many other hydrolyzing agents in the presence of protein breakdown products. In an attempt to find a suitable hydrolyzing agent which would ensure the stability of the thiolimidazole ring many methods were tried but thus far without complete success. Until such a procedure is evolved no final conclusion can be reached as to the presence or absence of the thiolimidazole ring in the protein molecule.
Item Citations and Data