Partial Nucleotide Sequences of Cysteine Proteinase Genes of Trichomonas tenax

Abstract

We cloned DNA fragments of cysteine proteinases (CPs) genes of Trichomonas tenax (T. tenax) and analyzed their nucleotide sequences in order to develope DNA probes. Initially, we constructed a pair primers (a and b) to amplify the CP genes of T. tenax, and obtained approximately 550-bp fragments by PCR. We then cloned the PCR fragments into pGEM-T vector and then isolated 150 clones. The inserts were sequenced and they were 498 to 513 by long. From the DNA sequences, amino acid sequences were deduced and 26 out of 150 DNA fragments were suggested to be CP gene. The 26 clones were divided into three groups, based on the amino acid sequences, and were designated CP-6, CP-8 and CP-25. By comparing the amino acid sequences with those of CPs, papain, cathepsin B and L, CPs of other protozoa, it was suggested that CPs of T tenax are more closely related to those of T. vaginalis (75-79%).