观赏凤梨烯醇酶基因的克隆及分析

Cloning and Sequence Analysis of Enolase Gene from Ornamental Bromeliads

烯醇酶催化着糖酵解途径中的唯一一步脱水反应,与植物的抗逆性有着密切的联系.基于前期从擎天凤梨全长cDNA文库中获得的烯醇酶基因的EST单克隆,进行引物步移测序,获得其全长cDNA序列.序列长1 703bp,编码445个氨基酸残基,命名为GoEnolase1(GenBank登录号JN896863),蛋白质理论分子质量为47.9kD,等电点为5.7,包含1个TIM磷酸结合超家族保守区,二级结构主要由α螺旋(44.49%)、随机卷曲(33.71%)、延伸链(13.71%)和β转角(8.09%)组成.系统进化树分析表明,GoEnolase1蛋白与水稻、玉米、油棕等的烯醇酶蛋白聚为一类,它们的亲缘关系最近.

Enolase catalyze only one-step dehydration reaction in glycolytic pathway,and relate closely to plant stress resistance. Based on EST monoclones of enolase gene obtained from bromeliads full length cD- NA library of ornamental bromeliads,its full length cDNA sequence was obtained by Primer Walking se- quencing. The gene,named for GoEnolasel （GenBank accession No. JN896863） ,consisted of 1 703 bp cD- NA sequence,1 335 bp ORF（open reading frame） which encoded a protein with 445 amino acids residues, and a putative protein which was 47.9 kD at estimated molecular weight,5.7 at isoelectric point and had a ＇TIM-phosphate-binding superfamily＇ conservative domain. The secondary structure of the protein was composedof alpha helix （44. 49%）,random coil （33. 71%）,extend strand （13. 71%） and beta turn （8.09%） by SPOMA analysis. Furthermore, its tertiary structure was also build based on A chain of 2PSN. Through phylogenetic tree analysis,GoEnolasel was gather to a same group with enolase protein in Oryza sativa ,Zea rnays and Elaeis guineensis. The research was beneficial to breeding for stress resistance in ornamental bromeliads.