Glycolytic enzymes of Candida albicans are nonubiquitous immunogens during candidiasis

A cDNA library was made with mRNA from Candida albicans grown under conditions favoring the hyphal form. The library was screened for sequences that encode immunogenic proteins by using pooled sera from five patients with oral candidiasis and five uninfected patients. Most of these patients were human immunodeficiency virus positive. From 40,000 cDNA clones screened, 83 positive clones were identified. Of these, 10 clones were chosen at random for further analysis. None of these 10 cDNAs were derived from a multigene family. The 5' and 3' ends of all 10 clones were analyzed by DNA sequencing. Two cDNAs were separate isolates of a sequence with strong homology to pyruvate kinase genes from other fungi (59 to 73%) and humans (60%). A third cDNA had strong sequence homology to the Saccharomyces cerevisiae and Kluyveromyces lactis alcohol dehydrogenase genes (68 to 73%). A fourth cDNA was homologous (81%) to an S. cerevisiae protein of unknown function. The functions of the remaining six C. albicans cDNAs are not known. A more detailed analysis of the clones encoding glycolytic enzymes revealed that sera from few patients recognized them as antigens. Therefore, although glycolytic enzymes constitute a group of C. albicans proteins that are immunogenic during oral and esophageal infections, their detection cannot be exploited as an accurate marker of infection.