Cloning and expression of a gene encoding a T-cell reactive protein from coccidioides immitis: homology to 4-hydroxyphenylpyruvate dioxygenase and the mammalian F antigen

Abstract

The gene which encodes a previously described T-cell reactive protein (TCRP) of the human fungal pathogen Coccidioides immitis (Ci) was cloned and sequenced. Both the genomic and cDNA sequences were determined. The transcription start point was confirmed. The tcrP gene has three introns and a 1197-bp ORF which translates to a 399-amino-acid (aa) protein (45.2 kDa). The predicted protein has approx. 50% aa sequence identity and 70% similarity to mammalian 4-hydroxyphenylpyruvate dioxygenase (HPPD) proteins and mammalian F-antigens. Expression of the Ci tcrP in Escherichia coli resulted in production of a deep brown pigment, consistent with E. coli expression of the bacterial HPPD homolog from Shewanella colwelliana. The TCRP is likely the Ci form of HPPD.