Influence of oxalysine (i-677) on the incorporation of lysine and its subcellular distribution

Oxalysine (I-677) was found to be an antitumor antibiotic with a simple chemical structure very similar to lysine. In this paper, we investigated the effect of I-677 0n protein biosynthesis, in particu- lar the synthesis of histone. When [14C]lysine or [3H]lysine was used as a precursor, a 17% inhibition of protein synthesis in vitro and a 59% inhibition on biosynthesis of histone in vivo were noted. But such an inhibitory effect of I-677 was not seen in the experiments using [3H]leu_cine as a precursor. The subcellular distribution of I-677 in liver and tumor of mice bearing sarcoma was determined by a microbiological as-say. The drug content was highest in the soluble cytoplasmic fraction.