【摘要】 利用已报道的α-淀粉酶基因序列的保守区域设计引物,通过聚合酶链式反应(PCR)获得了高温球菌Thermococcus sp. HJ21的耐高温酸性α-淀粉酶基因的部分序列。通过对该序列的同源性比较分析发现,高温球菌Thermococcus sp. HJ21与热水高温球菌Thermococcus hydrothermalis和Thermococcus sp. OGL-20P的亲缘关系最近,序列相似度达到95%以上;利用Swiss Model预测该基因产物的3级结构,显示其具有典型的(β/α)8桶状结构;通过分析密码子的使用情况得知,该α-淀粉酶存在着密码子的兼并性和使用的偏向性问题。更多还原

【Abstract】 A fragment of α-amylase gene(1164bp) was cloned,sequenced and analyzed from a hyperthermophilic archae Thermococcus sp.HJ21 by PCR method,where the primers were designed via analysis of the known α-amylase on the website.The results of phylogenetic analysis showed that the similarities of α-amylase gene with homologous gene in Thermococcus hydrothermalis and Thermococcus sp.OGL-20P were over 95%.There were problems of degenerate and preference of codon usage in α-amylase through analysing the sequence of amimo acid.And the deduced protein three-tier structure of α-amylase with Swiss Model displayed that there was a typical(β/α)8 structure on the protein three-tier structure.更多还原