Amino Acid Metabolism of the Brain. (VII) Transamination in the Growing Chick Embryo Brain

Using the chick-embryo brains in its various developmental stage and by means of paperchromatography. the author studied transamination of 15 different α-amino acids, 4 ω-amino acids, and α-ketoglutaric acid from embryo-chemical standpoint, and investigated the relationship between the germination, functional activity and amino acid metabolism in the growing chick embryo brains. The following are the resnlts. 1. In the early stage of chick embryo brain which begins to germinate and develope, only a minimal transaminase activity can be recognized, but on about 11th embryonic day the activity grown gradually and consistently. On the day of hatching the transaminase activity is almost the same as in a chick. 2, Aspartic acid, alanine, isolecine, leucine, valine, norvalin, tyrosine, ornithine and β-oxy-γ-amino acid, alanine, isoleuciue, leucine, valine, norvaline and cysteic acid immediately before hatching reaches about the same as found in other maturede animals such as mous (8) and dog (10).