一株海洋细菌铁吸收调节蛋白(Fur)基因的克隆和表达

对海洋细菌来说铁是一种必需元素,对铁吸收与利用的调控在细菌生长和防止铁毒性中起重要作用,在革兰氏阴性细菌中,铁的代谢由铁吸收调节蛋白(Fur) 来调控.橙色交替单胞菌是1种具有广泛抑菌谱的有益菌,本研究克隆表达了橙色交替单胞菌的fur基因,并分析了其相关特征.该基因序列中包含447bp的开放阅读框,编码148个氨基酸残基的蛋白,推导的相对分子量为16.637 kD,与GenBank报道的革兰氏阴性菌的相应序列同源性很高,其中氨基酸序列的中段从G47位至D104位,为高度保守区域.在限铁和富铁培养条件下铁载体分泌量的结果分析表明,fur基因可在大肠杆菌中大量表达,为进一步研究Fur蛋白的结构与功能打下基础.

CLONING, EXPRESSION AND CHARACTERIZATION ANALYSIS OF THE FUR GENE IN ALTEROMONAS AURANTIA

Iron is an essential element for marine bacteria. Regulation of iron uptake and utilization is critical for bacterial growth and prevention of iron toxicity. Iron metabolism is regulated by the ferric uptake regulator (Fur) protein in Gram-negative bacteria. Alteromonas aurantia, a Gram-negative bacterium, has broad spectrum antibacterial activity as one of the probiotic. In present research, the fur gene of Alteromonas aurantia was cloned, sequenced and characterized. It contained an open reading frame of 447 bp encoding a 148 amino acids protein. Highly conserved sequence from G47 to D104 existed in the middle of the translated amino acid sequence. The secretion of siderophores indicated that the fur gene could over-express in E. coli QC1732 under iron-rich or iron-deficient medium, which can provide a base for further research on the structure and functions of fur protein.