Keeler C L, Hnatow L L, Whetzel P L, Dohms J E
Delaware Agricultural Experiment Station, Department of Animal and Food Sciences, College of Agricultural Sciences, University of Delaware, Newark 19717-1303, USA.
Infect Immun. 1996 May;64(5):1541-7. doi: 10.1128/iai.64.5.1541-1547.1996.
A 150-kDa cytadhesin-like protein from Mycoplasma gallisepticum has been identified. A previously described 583-bp fragment (J.E. Dohms, L.L. Hnatow, P. Whetzel, R. Morgan and C.L. Keeler, Jr., Avian Dis. 37:380-388, 1993) was used to probe a genomic library of M. gallisepticum DNA. An 8.0-kb SacI fragment was identified, cloned, and partially sequenced. Analysis of the resulting 3,750-bp sequence revealed the presence of a 3,366-nucleotide open reading frame, mgc1. The 1,122-amino-acid protein encoded by this open reading frame, MGC1, has characteristics of a class I membrane protein and has homology with the MgPa cytadhesin of Mycoplasma genitalium (26.3%) and the P1 cytadhesin of Mycoplasma pneumoniae (28.7%). A portion of MGC1 was expressed as a glutathione S-transferase fusion protein and used to produce antiserum in rabbits. The antiserum recognizes a 150-kDa protein from M. gallisepticum. The protein is sensitive to trypsin, confirming that it is surface exposed. Primer extension analysis indicates that the mgc1 RNA starts within an upstream open reading frame, suggesting complex control of its expression. This is the first description of a functional gene from M. gallisepticum showing homology to cytadhesin genes from human mycoplasmas.
已鉴定出鸡毒支原体的一种150 kDa细胞黏附素样蛋白。用先前描述的一个583 bp片段（J.E. 多姆斯、L.L. 纳托夫、P. 惠策尔、R. 摩根和小C.L. 基勒，《禽病学》37:380 - 388, 1993）探测鸡毒支原体DNA的基因组文库。鉴定出一个8.0 kb的SacI片段，将其克隆并进行部分测序。对所得3750 bp序列的分析揭示存在一个3366核苷酸的开放阅读框mgc1。由该开放阅读框编码的1122个氨基酸的蛋白MGC1具有I类膜蛋白的特征，并且与生殖支原体的MgPa细胞黏附素（26.3%）和肺炎支原体的P1细胞黏附素（28.7%）具有同源性。MGC1的一部分作为谷胱甘肽S - 转移酶融合蛋白表达，并用于在兔中制备抗血清。该抗血清识别鸡毒支原体的一种150 kDa蛋白。该蛋白对胰蛋白酶敏感，证实它暴露于表面。引物延伸分析表明mgc1 RNA起始于一个上游开放阅读框内，提示其表达受到复杂调控。这是首次描述鸡毒支原体中一个与人类支原体细胞黏附素基因具有同源性的功能基因。
