Layh-Schmitt G
ZMBH, Universität Heidelberg, Germany.
Zentralbl Bakteriol. 1993 Apr;278(2-3):287-95. doi: 10.1016/s0934-8840(11)80845-5.
The P1 attachment protein gene of Mycoplasma pneumoniae is flanked by two open reading frames with a coding capacity for two proteins of 28 kDa (ORF4) and 130 kDa (ORF6), respectively. An operon-like organization in the order ORF4-P1-ORF6 was proposed by Inamine et al. (11). Instead of an expected 130 kDa protein, two proteins of 40 and 90 kDa were identified as the gene product of ORF6 which might arise from cotranslational cleavage (18). After purification of both proteins, the N-terminal amino acid of the 90 kDa protein was determined. Thus, we identified the putative cotranslational cleavage site before amino acid position 455 (R) (15). Biochemical and immunological studies indicate that both proteins are membrane-associated, exhibiting surface-exposed regions (15). Since a wild-type-derived mutant lacking the 40 as well as the 90 kDa protein shows reduced attachment to host cells we suggest that the ORF6 encodes for two proteins which contribute to proper adherence of M. pneumoniae to host cells.
肺炎支原体的P1附着蛋白基因两侧分别有两个开放阅读框，其编码能力分别为两种蛋白质，即28 kDa（ORF4）和130 kDa（ORF6）。稻岭等人（11）提出了一种类似操纵子的组织形式，顺序为ORF4 - P1 - ORF6。ORF6的基因产物不是预期的130 kDa蛋白质，而是鉴定出两种蛋白质，分别为40 kDa和90 kDa，这可能是共翻译切割产生的（18）。纯化这两种蛋白质后，测定了90 kDa蛋白质的N端氨基酸。因此，我们确定了在氨基酸位置455（R）之前的假定共翻译切割位点（15）。生化和免疫学研究表明，这两种蛋白质都与膜相关，具有表面暴露区域（15）。由于一个缺失40 kDa和90 kDa蛋白质的野生型衍生突变体对宿主细胞的附着减少，我们认为ORF6编码两种有助于肺炎支原体正确黏附于宿主细胞的蛋白质。
