BQP35 is a novel member of the intrinsically unstructured protein (IUP) family which is a potential antigen for the sero-diagnosis of Babesia sp. BQ1 (Lintan) infection.
A new gene of Babesia sp. BQ1 (Lintan) (BQP35) was cloned by screening a merozoite cDNA expression library with infected sheep serum and using rapid amplification of cDNA ends (RACE). The nucleotide sequence of the cDNA was 1140bp with an open reading frame (ORF) of 936bp encoding a 35-kDa predicted polypeptide with 311 amino acid residues. Comparison of BQP35 cDNA and genomic DNA sequences showed that BQP35 does not possess an intron. Recombinant BQP35 (rBQP35), expressed in a prokaryotic expression system, showed abnormally slow migration on SDS-PAGE. Gel shifting, amino acid sequence and in silico disorder region prediction indicated that BQP35 protein has characteristics of intrinsically unstructured proteins (IUPs). This is the first description of such proteins in the Babesia genus. BQP35 induced antibodies production as early as one week after Babesia sp. BQ1 (Lintan) infection in sheep. No cross-reaction was observed with sera from sheep infected with other ovine piroplasms dominant in China, except with Babesia sp. Tianzhu. The interest of BQP35 as a diagnostic antigen is discussed.
State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu 730046, PR China.
Guiquan
G
Guan
Emmanuelle
E
Moreau
Junlong
J
Liu
Miling
M
Ma
Hélène
H
Rogniaux
Aihong
A
Liu
Qingli
Q
Niu
Youquan
Y
Li
Qiaoyun
Q
Ren
Jianxun
J
Luo
Alain
A
Chauvin
Hong
H
Yin
D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001403:Babesia / Q000145:classification / Q000378:metabolism*; D001404:Babesiosis / Q000175:diagnosis / Q000469:parasitology*; D001483:Base Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005786:Gene Expression Regulation; D015723:Gene Library; D008969:Molecular Sequence Data; D015800:Protozoan Proteins; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000175:diagnosis / Q000469:parasitology*
D000953:Antigens, Protozoan; D015800:Protozoan Proteins