SEQUENCE-ANALYSIS AND EXPRESSION OF THE 2 GENES FOR ELONGATION FACTOR-1-ALPHA FROM THE DIMORPHIC YEAST CANDIDA-ALBICANS

Two Candida albicans genes that encode the protein synthesis factor elongation factor 1α (EF-1α) were cloned by using a heterologous TEF1 probe from Mucor racemosus to screen libraries of C. albicans genomic, DNA. Sequence analysis of the clones showed that regions of DNA flanking the coding regions of the two genes were not homologous, verifying the presence of two genes, called TEF1 and TEF2, for EF-1α in C. albicans. The coding regions of TEF1 and TEF2 differed by only five nucleotides and encoded identical EF-1α proteins of 458 amino acids. Both genes were transcribed into mRNA in vivo, as shown by hybridization of oligonucleotide probes, which found specifically to the 3' nontranslated regions of TEF1 and TEF2, respectively, to C. albicans total RNA in Northern (RNA) blot analysis. The predicted EF-1α protein of C. albicans was more similar to Saccharomyces cerevisiae EF-1α than to M. racemosus EF-1α. Furthermore, codon bias and the promoter and termination signals of the C. albicans EF-1α proteins were remarkably similar to those of S. cerevisiae EF-1α. Taken together, these results suggest that C. albicans is more closely related to the ascomycete S. cerevisiae than to the zygomycete M. racemosus.