Candida species-C.albicans, C.zeylanoides, C.lusitaniae, codon is translated as serine. However, in most cases, C.tropicalis, C.melbiosica, C.parapsilosis, C.guilliermonthe serine tRNAs responsible for this non-universal dii and C.rugosa-were found to utilize the codon CUG decoding (tRNA Ser CAG) accept in vitro not only serine, for serine instead of leucine, all having tRNA Ser CAG as but also, to some extent, leucine. Nucleotide replacethe mediator in the unusual decoding (Ohama et al., 1993 ; ment experiments indicated that m 1 G37 is critical for Ueda et al., 1994) . Several other investigators have also leucylation activity. This finding was supported by the shown that the codon CUG is actually translated as serine fact that the tRNA Ser CAGs possessing the leucylation in vivo in C.albicans and C.maltosa (Santos and Tuite, activity always have m 1 G37, whereas that of Candida 1995a; Sugiyama et al., 1995; Zimmer and Schunck, 1995) .