Cerebral monoamine neurotransmitters in progeny of pyridoxine-deficient rats: H. Choi and S. A. Kang, Department of Food and Nutrition, Seoul National University, Seoul 151, Korea

Abstract

Prothymosin α has been purified from human thymus and its amino acid sequence determined, except for a 15 amino acid segment including 10 glutamyl residues near the middle of the molecule. Like prothymosin α from rat thymus [A. A. Haritos, R. Blacher, S. Stein, J. Caldarella, and B. L. Horecker (1985) Proc. Natl. Acad. Sci. USA82, 343–346], human prothymosin contains the thymosin α1 sequence at its NH2-terminus. It contains a total of 109–110 residues compared to 111–112 for rat prothymosin α, with deletions corresponding to positions Gln39 and Lys108 of the rat polypeptide. Human prothymosin α also differs from rat prothymosin α at positions corresponding to residues 87, 92, and 102 of the latter, with substitutions of alanine for proline, alanine for valine, and aspartic acid for glutamic acid, respectively. Human prothymosin is significantly less active than rat prothymosin in protecting mice against infection with Candida albicans and in stimulating release in vivo of migration inhibitory factor. Thus, the differences in amino acid sequences, present mainly the COOH-terminal half of the polypeptides, may determine species specificity in boilogical properties.