Wyszyńska Agnieszka, Tomczyk Karolina, Jagusztyn-Krynicka Elzbieta K
Department of Bacterial Genetics, Institute of Microbiology, Warsaw University, Warszawa, Poland.
Acta Biochim Pol. 2007;54(1):143-50. Epub 2007 Mar 9.
Campylobacter is an asaccharolytic microorganism which uses amino acids as a source of carbon and energy. CjaC/HisJ is a ligand-binding protein, a component of the ABC transport system. Campylobacter CjaC/HisJ is post-translationally modified by glycosylation. The number of glycosylation motifs present in the CjaC protein is species-specific. C. coli CjaC has two and C. jejuni one motif (E/DXNYS/T) which serves as a glycan acceptor. Although the two C. coli CjaC motifs have identical amino-acid sequences they are not glycosylated with the same efficiency. The efficacy of CjaC glycosylation in Escherichia coli containing the Campylobacter pgl locus is also rather low compared to that observed in the native host. The CjaC localization is host-dependent. Despite being a lipoprotein, CjaC is recovered in E. coli from the periplasmic space whereas in Campylobacter it is anchored to the inner membrane.
弯曲杆菌是一种不分解糖类的微生物，它利用氨基酸作为碳源和能源。CjaC/HisJ是一种配体结合蛋白，是ABC转运系统的一个组成部分。弯曲杆菌CjaC/HisJ在翻译后会发生糖基化修饰。CjaC蛋白中存在的糖基化基序数量具有物种特异性。大肠杆菌CjaC有两个基序，空肠弯曲杆菌有一个基序（E/DXNYS/T），该基序作为聚糖受体。尽管大肠杆菌的两个CjaC基序具有相同的氨基酸序列，但它们的糖基化效率并不相同。与在天然宿主中观察到的情况相比，在含有弯曲杆菌pgl基因座的大肠杆菌中，CjaC糖基化的效率也相当低。CjaC的定位取决于宿主。尽管CjaC是一种脂蛋白，但在大肠杆菌中它是从周质空间回收的，而在弯曲杆菌中它锚定在内膜上。
