Kung'u M W, Dalrymple B P, Wright I G, Peters J M
CSIRO, Long Pocket Laboratories, Indooroopilly, Australia.
Mol Biochem Parasitol. 1992 Oct;55(1-2):29-38. doi: 10.1016/0166-6851(92)90124-3.
Bovine polyclonal antisera to Babesia bigemina antigens separated by phenyl-Sepharose chromatography were used to screen a B. bigemina lambda gt11 cDNA expression library. Eleven B. bigemina-specific cDNA clones were studied in detail. DNA sequencing of 2 representative clones identified open reading frames encoding polypeptides representing the carboxy-termini of 2 different proteins. Both polypeptides contained a related central motif of tandem repeats flanked by a highly conserved carboxy-terminal region, but the sequences preceding the repeats were not related. Hybridisation and restriction enzyme analysis of the cDNA clones indicated that they were derived from a family of at least nine related, but not identical genes. Four different members of the gene family have been isolated from a B. bigemina lambda EMBL3 genomic library. The genes are not closely linked and they occur on the largest and smallest B. bigemina chromosomes resolved by pulsed field gel electrophoresis (PFGE). Antibodies raised against the native antigens and purified on recombinant fusion proteins bound to multiple proteins (50-70 kDa) in the original B. bigemina antigenic fractions.
用经苯基 - 琼脂糖层析分离的牛巴贝斯虫双芽变种抗原的多克隆抗血清筛选双芽巴贝斯虫λgt11 cDNA表达文库。对11个双芽巴贝斯虫特异性cDNA克隆进行了详细研究。对2个代表性克隆的DNA测序确定了编码代表2种不同蛋白质羧基末端多肽的开放阅读框。两种多肽均含有一个由高度保守的羧基末端区域侧翼的串联重复相关中央基序，但重复序列之前的序列不相关。cDNA克隆的杂交和限制性酶切分析表明它们来自一个至少有9个相关但不相同基因的家族。该基因家族的4个不同成员已从双芽巴贝斯虫λEMBL3基因组文库中分离出来。这些基因没有紧密连锁，它们出现在通过脉冲场凝胶电泳（PFGE）解析的双芽巴贝斯虫最大和最小染色体上。针对天然抗原产生并在与原始双芽巴贝斯虫抗原组分中多种蛋白质（50 - 70 kDa）结合的重组融合蛋白上纯化的抗体。
