Characterization of variants of the gene encoding the p55 antigen in Pneumocystis from rats and mice.
Variants of the p55 gene in rat-derived Pneumocystis carinii have been identified and its counterpart in mouse-derived P. carinii f. sp. muris has been cloned. By PCR amplification of P. carinii genomic DNA, five variants were identified that differed from each other in size and sequence, primarily in the number and size of encoded amino acid repeats. For P. carinii f. sp. muris, a single PCR fragment (471 bp) was obtained, which contained an incomplete ORF encoding a 157 aa protein that was most similar to a p55 variant in P. carinii, with nucleotide and amino acid sequence identity of 79 and 68 %, respectively. Southern blot analysis revealed the presence of more than one copy of the p55 gene in both Pneumocystis species. Thus, like other Pneumocystis antigens, p55 exhibits polymorphism that could potentially benefit the organism in host interactions.
Ma
Liang
L
Critical Care Medicine Department, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
Kutty
Geetha
G
Critical Care Medicine Department, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
Jia
Qiuyao
Q
Critical Care Medicine Department, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
Kovacs
Joseph A
JA
Critical Care Medicine Department, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
D000595:Amino Acid Sequence; D000818:Animals; D000946:Antigens, Fungal / Q000235:genetics*; D001483:Base Sequence; D005800:Genes, Fungal; D014644:Genetic Variation; D051379:Mice; D016513:Mice, SCID; D008969:Molecular Sequence Data; D045363:Pneumocystis carinii / Q000235:genetics* / Q000276:immunology; D051381:Rats
D000946:Antigens, Fungal