L.paracasei W2芳香族氨基酸转氨酶基因克隆与序列分析

Clone and Sequence Analysis of Aromatic Aminotransferase Gene from Lactobacillus paracasei

分析和预测副干酪乳杆菌(L.paracasei W2)芳香族氨基酸转氨酶基因及其编码蛋白的结构和特性,以指导其生物学功能的试验研究。以L.paracasei W2基因组为模板扩增1 164 bp的转氨酶基因序列,对其编码的蛋白进行疏水性分析、磷酸化位点预测、二级、三级结构预测并构建分子进化树。结果表明该基因编码387个氨基酸,理论相对分子质量是41961.2 Da,等电点为6.03,具有完整的保守结构域和保守功能位点,该蛋白有两个跨膜螺旋区,与干酪乳杆菌的转氨酶进化关系最近。

The structure and characteristics of Aromatic Aminotransferase from L. paracasei W2 were analyzed and predicted, in order to guide the experimental research for its biological function and application. The genomic DNA of L.paracasei W2 was used as the template to amplify the Aromatic Aminotransferase Gene, the fragment was about 1 164 bp.The hydrohobicity analysis, phospholyration sites prediction, secondary and tertiary structure prediction, multiple sequences alignments and the phylogenetic tree were carried out to the sequence by bioinformatics sofeware package. The results showed that the gene coding for 387 amino acids, molecular weight of Aromatic Aminotransferase was predicted to be 41 961.2 Da and its isoelectric point was 6.03.The coding protein was demonstrated to have a complete conserved domain, conserved functional sites and two trans-membrane regions in the deduced amino acid sequence. Aromatic Aminotransferase Gene from Lactobacillus paracasei has high homology with Aromatic Aminotransferase Gene from Lactobacillus casei.