Cloning and sequence analysis of the cDNA for a protein from Coccidioides immitis with immunogenic potential.

We have cloned and sequenced the cDNA encoding an immunoreactive protein from the pathogenic fungus Coccidioides immitis which stimulates human T cells and has been associated with protective vaccines in mice. The transcript contained an open reading frame encoding 194 amino acids with a calculated molecular weight of 19.5 kDa, a 151 base 5' untranslated region (UTR), and a 468 base 3'UTR. A four member repeat motif, usually thr-ala-glu-pro, exists for amino acids 98 through 141. Deduced amino acid sequence derived from the cDNA was identical with previously determined internal amino acid sequence from the native protein, and goat antiserum raised against the purified fungal protein reacted with an inducible fusion protein translated from this cDNA. Using this cDNA to produce recombinant protein will allow direct testing of its role in human immunity to coccidioidomycosis and may lead to new diagnostic tests.