He Jian-yu, Chi Chang-feng, Liu Hui-hui
National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China.
National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China.
Dev Comp Immunol. 2014 Nov;47(1):1-5. doi: 10.1016/j.dci.2014.06.010. Epub 2014 Jun 27.
Superoxide dismutases (SODs) are ubiquitous family of metalloenzymes involved in protecting organisms from excess reactive oxygen species damage. In this paper, a novel intracellular Cu/ZnSOD from Sepiella maindroni (designated as SmSOD) was identified and characterized. The full-length cDNA sequence of SmSOD (GenBank accession No. KF908850) was 709 bp containing an open reading frame (ORF) of 459 bp, encoding 153 amino acid residues peptide with predicted pI/MW (6.02/15.75 kDa), a 131 bp-5'- and 116 bp-3'- untranslated region (UTR). BLASTn analysis and phylogenetic relationship strongly suggested that the sequence shared high similarity with known Cu/Zn SODs. Several highly conserved motifs, including two typical Cu/Zn SOD family domains, two conserved Cu-/Zn-binding sites (H-47, H-49, H-64, H-120 for Cu binding, and H-64, H-72, H-81, D-84 for Zn binding) and intracellular disulfide bond (C-58 and C-146), were also identified in SmSOD. Time-dependent mRNA expression of SmSOD in hepatopancreas was recorded by quantitative real-time RT-PCR after Vibrio harveyi injection and Cd(2+) exposure. The results indicated that SmSOD was an acute-phase protein involved in the immune responses against pathogens and biological indicator for metal contaminants in aquatic environment.
超氧化物歧化酶（SODs）是一类广泛存在的金属酶家族，参与保护生物体免受过量活性氧物种的损伤。本文鉴定并表征了一种来自曼氏无针乌贼的新型细胞内铜锌超氧化物歧化酶（命名为SmSOD）。SmSOD的全长cDNA序列（GenBank登录号：KF908850）为709 bp，包含一个459 bp的开放阅读框（ORF），编码一个153个氨基酸残基的肽段，预测的pI/MW为（6.02/15.75 kDa），5'端有131 bp和3'端有116 bp的非翻译区（UTR）。BLASTn分析和系统发育关系强烈表明该序列与已知的铜锌超氧化物歧化酶具有高度相似性。在SmSOD中还鉴定出了几个高度保守的基序，包括两个典型的铜锌超氧化物歧化酶家族结构域、两个保守的铜/锌结合位点（用于结合铜的H-47、H-49、H-64、H-120，以及用于结合锌的H-64、H-72、H-81、D-84）和细胞内二硫键（C-58和C-146）。在注射哈维氏弧菌和暴露于Cd(2+)后，通过定量实时RT-PCR记录了SmSOD在肝胰腺中的时间依赖性mRNA表达。结果表明，SmSOD是一种参与针对病原体免疫反应的急性期蛋白，也是水环境中金属污染物的生物指标。
