Raphael Brian H, Joens Lynn A
Department of Veterinary Science and Microbiology, The University of Arizona, Tucson 85721, USA.
Can J Microbiol. 2003 Nov;49(11):727-31. doi: 10.1139/w03-086.
Among strains of Campylobacter jejuni, levels of ferrous iron (Fe2+) uptake was comparable. However, C. jejuni showed a lower level of ferrous iron uptake than Escherichia coli. Consistent with studies of E. coli, Fe2+ uptake in C. jejuni was significantly enhanced by low Mg2+ concentration. The C. jejuni genome sequence contains a single known ferrous iron uptake gene, feoB, whose product shares 50% amino acid identity to Helicobacter pylori FeoB and 29% identity to E. coli FeoB. However, Fe2+ uptake could not be attributed to FeoB for several reasons. Site-directed mutations in feoB caused no defect in 55Fe2+ uptake. Among C. jejuni strains, various nucleotide alterations were found in feoB, indicating that some C. jejuni feoB genes are defective. In addition, uptake could not be attributed to the magnesium transporter CorA, since no reduction in 55Fe2+ uptake was observed in the presence of a CorA-specific inhibitor.
在空肠弯曲菌菌株中，亚铁（Fe2+）摄取水平相当。然而，空肠弯曲菌的亚铁摄取水平低于大肠杆菌。与对大肠杆菌的研究一致，低镁离子浓度显著增强了空肠弯曲菌对Fe2+的摄取。空肠弯曲菌基因组序列包含一个已知的亚铁摄取基因feoB，其产物与幽门螺杆菌FeoB的氨基酸同一性为50%，与大肠杆菌FeoB的同一性为29%。然而，由于几个原因，Fe2+摄取不能归因于FeoB。feoB中的定点突变未导致55Fe2+摄取缺陷。在空肠弯曲菌菌株中，feoB中发现了各种核苷酸改变，表明一些空肠弯曲菌feoB基因存在缺陷。此外，摄取不能归因于镁转运蛋白CorA，因为在存在CorA特异性抑制剂的情况下未观察到55Fe2+摄取减少。
