蛇苔细胞色素C（Cyt C）的序列分析及功能预测

通过核酸序列比对，在蛇苔cDNA文库中获得细胞色素C（Cyt C）基因序列，并对其编码的蛋白质产物从同源性、氨基酸组成、理化性质、亚细胞位点、结构和功能等进行生物信息学分析和预测。结果表明，该cDNA序列具有完整的开放阅读框（ORF，104—442bp），推测编码蛋白为112个氨基酸，与向日葵、荞麦、玉米等Cyt C存在着较高的保守性（相似性分别为84％、85％和84％），同属于细胞色素C超家族；蛇苔CytC蛋白的分子量为11998．7Da，不含信号肽，成熟的CytC起始于Ala2，其活性位点为Cys23、Cys26、His27和Met89；对蛋白质的翻译后修饰预测表明Ala2存在乙酰化修饰，Lys81和Lys95分别进行三甲基赖氨酸修饰。这些特点与其他植物CytC保持一致，表明该基因为蛇苔cyt c基因，在进化上相对保守。

Sequence Analysis and Function Predication of Cyt C from Conocephalum conicum (L.) Dum.

Through nucleotide blast the cyt c gene was gained from the cDNA library of Conocephalum conicum, and its produce was analyzed in the following aspects：the homology, composition of amino acids, physico-chemical characters, subcellular location, tertiary structure, function and so on by bioinformational tools. The result indicates the sequence has a complete open read frame （104 -442 bp）, and it encodes 112 amino acids which has a high homology with Helianthus annuus, Fagopyrum esculentum, Zea mays and other plants Cyt Cs. They all belong to Cytochrome C superfamily. With molecular weight 11998.7 Da and no signal peptide, the sequence of Conocephalum conicum Cyt C starts Ala2 and takes Cys23 ,Cys26,His27 and Met89 as its active sites. What is more Ala2 is acetylized and the sites Lys81/ Lys95 are modified to be trimethyllysine. All these characteristics keep in line with other plant Cyt Cs, which illuminates the sequence we got is cyt c gene which is conserved in the course of evolution.