Abstract
1. An unidentified diazo-positive substance of the fruit-fly, D. melanogaster, was compared with synthetic xanthurenic acid in regard to the Rf value in paper chromatography, color reactions, paper electro-phoretic behaviors, and ultraviolet absorption. It was found that both substances were identical.
2. The wild strain and various eye-color mutant strains (including five recessive and six double recessive strains) were examined for the presence of xanthurenic acid. The wild, st, bw, se, and se st strains were positive for it, while the v, cn, v bw, cn, bw, bw st, v se, and cn se strains were negative. These results are discussed from the point of view of tryptophan metabolism.
The authors wish to express their gratitude to Professor Yahito Kotake of the Wakayama Medical College for the generous gift of synthetic xanthurenic acid, and to the Mizuno Laboratory, Faculty of Pharmacy, Kanazawa University, for the measurements of ultraviolet absorption. Thanks are also due to Dr. G. Tomita of the Tohoku University for his kindness in reviewing this manuscript.
This work was supported by a Grant in Aid for Miscellaneous Scientific Research from the Ministry of Education.
