Spierings G, Ockhuijsen C, Hofstra H, Tommassen J
Department of Molecular Cell Biology, University of Utrecht, Netherlands.
FEMS Microbiol Lett. 1992 Dec 1;78(2-3):199-204. doi: 10.1016/0378-1097(92)90025-j.
The phoE gene of Citrobacter freundii, encoding a pore-forming outer membrane protein, was cloned and its nucleotide sequence was determined. The homologies in terms of identical amino acids between the C. freundii PhoE protein and those of Escherichia coli, E. cloacae and Klebsiella pneumoniae were 90%, 86% and 84%, respectively. Two synthetic oligonucleotides, corresponding to hypervariable, cell surface-exposed regions of the protein, were tested for their specificity in polymerase chain reactions. They were specific for the species C. freundii, i.e., no reaction was detected with 35 non-C. freundii strains tested, including 17 Salmonella, two C. amalonaticus and three C. diversus strains, whereas all five C. freundii strains tested were correctly recognized.
弗氏柠檬酸杆菌的phoE基因编码一种形成孔道的外膜蛋白，该基因被克隆并测定了其核苷酸序列。弗氏柠檬酸杆菌PhoE蛋白与大肠杆菌、阴沟肠杆菌和肺炎克雷伯菌的PhoE蛋白在相同氨基酸方面的同源性分别为90%、86%和84%。针对该蛋白高变的、暴露于细胞表面的区域设计了两条合成寡核苷酸，并在聚合酶链反应中测试了它们的特异性。它们对弗氏柠檬酸杆菌具有特异性，即在所测试的35株非弗氏柠檬酸杆菌菌株中未检测到反应，这些菌株包括17株沙门氏菌、2株无丙二酸柠檬酸杆菌和3株差异柠檬酸杆菌，而所测试的5株弗氏柠檬酸杆菌菌株均被正确识别。
