Some aspects of the metabolism of the developing chick embryo : the metabolism of 'biologically labile' methyl groups

• Main Author: Boyd, George Scott
• Format: Dissertation
• Language: English
• Published: University of Edinburgh 1951

Excluding inorganic ions and molecules, the methyl group is surely one of the simplest chemical units encountered in the living cell. This radical is found in biological material in covalent combination with various elements, yielding molecules well known to the organic chemist, which could be classified as follows:- (a) Methyl group attached to nitrogen, as in choline, creatine and adrenaline. (b) Methyl group attached to sulphur, as in methionin and dimethylthetin. (c) Methyl group attached to sulphur, as in methionin and dimethylthetin. attached to carbon, as in alanine, valine and thymine. (d) Methyl group attached to oxygen, as in alkaloids such as narcotine. (e) Methyl group attached to metalloids such as selenium, tellurium and arsenic, yielding selenides, tellurides and arsenides. Whilst the methylated nitrogen, sulphur and are widely distributed in the kingdoms, the methyl ethers and methylated metallic complexes are rareties, occurring in certain highly specialized organisms, or under non -physiological circumstances. For this and other reasons to be elaborated later, the subject of biological methylation was for long mainly confined to the study of methyl groups attached to nitrogen or sulphur and was only quite recently extended to include methyl - carbon compounds. The phenomena of synthesis, transport and degradation of the methyl group have occupied the attention of physiologists and biochemists during the greater part of the twentieth century. Although these problems have not been settled, the groundwork has been laid to open the way to a fuller elucidation of the role of the methyl radical in biochemical processes.