Knobloch J, Schreiber M
Bernhard-Nocht-Institut für Tropenmedizin, Hamburg, Federal Republic of Germany.
Am J Trop Med Hyg. 1990 Oct;43(4):373-9. doi: 10.4269/ajtmh.1990.43.373.
A 65 kDa protein (Bb65) has been identified as one of the major specific antigens of Bartonella bacilliformis, the causative agent of bartonellosis which is a bacterial infectious disease of inhabitants of the Andes. The gene encoding this antigen (7B2) was isolated from an expression library made directly from randomly generated fragments of B. bacilliformis genomic DNA using Bartonella antibodies raised in rabbits and sera of bartonellosis patients. The Bartonella 7B2 gene was expressed in Escherichia coli and the recombinant Bb65 protein was purified by column chromatography. Using polyclonal antibodies raised in rabbits, the antigen was shown to be present in all of 13 B. bacilliformis isolates from different Peruvian regions. Immune electron microscopy demonstrated the probable cytoplasmatic localization of Bb65. When applied to enzyme immunoassays, Bb65 sensitively and specifically bound to IgG antibody of sera of bartonellosis patients, convalescents, and immunes from various Peruvian regions. IgM antibody was not recognized by Bb65, neither was IgG antibody circulating during the first 2 weeks of illness. The amino-terminal amino acid sequence of Bb65 was 53% homologous to the 65 kDa heat shock protein of Mycobacterium tuberculosis.
一种65千道尔顿的蛋白质（Bb65）已被确定为杆菌状巴尔通体的主要特异性抗原之一，杆菌状巴尔通体是巴尔通体病的病原体，巴尔通体病是一种安第斯地区居民的细菌性传染病。编码该抗原的基因（7B2）是从一个表达文库中分离出来的，该文库直接由杆菌状巴尔通体基因组DNA的随机片段构建而成，使用的是兔源巴尔通体抗体和巴尔通体病患者的血清。杆菌状巴尔通体7B2基因在大肠杆菌中表达，重组Bb65蛋白通过柱层析法纯化。使用兔源多克隆抗体，该抗原在来自秘鲁不同地区的13株杆菌状巴尔通体分离株中均有发现。免疫电子显微镜显示Bb65可能定位于细胞质中。当应用于酶免疫测定时，Bb65能敏感且特异地与来自秘鲁不同地区的巴尔通体病患者、康复者和免疫者血清中的IgG抗体结合。Bb65不能识别IgM抗体，在疾病的前两周循环的IgG抗体也不能被识别。Bb65的氨基末端氨基酸序列与结核分枝杆菌的65千道尔顿热休克蛋白有53%的同源性。
