A 3.6 kb gene (ELF1) with homology to the ATP-binding cassette (ABC) gene family has been isolated from genomic libraries of Candida albicans. Members of this gene family include both membrane transport proteins which confer a drug-resistance phenotype, and proteins whose functions are associated with protein translation. ELF1 (Elongation Like Factor) showed greatest homology with a Saccharomyces cerevisiae ORF (YPL226W), whose function is unknown, and lower homology with fungal elongation factor 3 (EF-3) genes. In comparison, homology with a gene conferring a drug-resistant phenotype (CDR1) was low. To understand the function of ELF1 in C. albicans, gene-knockout experiments were conducted using the hisG-URA3-hisG disruption cassette. Both single-copy (heterozygote) and double-disrupted strains in ELF1 were isolated. Phenotypically, the disrupted strains grew more slowly than wild-type and produced a mixture of large, irregular cells and apparently normal cells.