Cloning and identification of the CDS region of the p55-v0 and p55-v3 gene in Pneumocystis carinii / 中国人兽共患病学报

ABSTRACT

This study sought to amplify the CDS region of p55-v0 and p55-v3 gene in Pneumocystis carinii (PC) and to analyze their sequences.The total RNA extracted from PC- infected lungs of rats were used as the template to amplify these genes by RT-PCR.The amplified products were connected to T-vector and transformed into E.coli DH5α.The recombinant T-vectors were selected in LB culture medium containing ampicillin.Then the positive clones of recombinants were identified by PCR and digested by restrictive endonuclease.After that the recombinant were sequenced and analyzed.It was found that the CDS region of p55-v0 gene contained 1245 bps,encoding 414 amino acids.The homology between this sequence and the one reported previously in nucleotide and amino acid were 99.8% and 100% respectively.Meanwhile,the CDS region of p55-v3 contained 1053 bps,encoding 350 amino acids.As compared with GenBank,the homology in nucleotide and amino acid was 99.9% and 100% respectively.However,the similarity in nucleotide between p55-v3 and p55-v0 was just 20.9%.In this study,the CDS regions of p55-v0 and p55-v3 gene were cloned successfully,and the high homology was found between p55-v0,p55-v3 and the one reported previously by sequence analysis,p55-v3 was different from p55-v0 in nucleotides and amino acids.This result would provide a basis for comparison of immunologic functions so as to explore the mechanism of action of the p55-v3 gene.