微藻脂滴蛋白的生物信息学分析

Bioinformatics analysis of microalgal lipid droplet proteins

试验旨在探究微藻脂滴蛋白的结构特征。采用生物信息学方法对微藻脂滴蛋白的理化性质、亲/疏水性、信号肽、跨膜结构域、双亲性α螺旋、二级结构、结构域、三级结构、保守基序、磷酸化位点进行了研究。结果显示,微拟球藻LDSP蛋白是稳定碱性的疏水蛋白,无信号肽,2个跨膜结构域分别形成双亲性α螺旋和疏水α螺旋,二级结构由α螺旋、延伸链、β转角和无规则卷曲组成,具有焦磷酸硫胺素中间结构域,三级结构漏斗状,C端存在保守基序,具有9个磷酸化位点。与微拟球藻LDSP蛋白不同,巴夫杜氏藻MLDP蛋白和雨生红球藻HOGP蛋白是酸性亲水蛋白,无跨膜结构域,与膜相互作用的序列形成双亲性α螺旋,具有橡胶延伸因子结构域,三级结构哑铃状,分别具有33、24个磷酸化位点。莱茵衣藻MLDP蛋白的结构特征介于两类特征之间。研究表明,微藻脂滴蛋白的结构发生分化,可能导致功能的不同。

The experiment was to explore the structural features of microalgal lipid droplet proteins.Bioinformatics methods were used to investigate the physicochemical properties,hydrophilicity/hydrophobicity,signal peptide,transmembrane domain,amphipathicα-helix,secondary structure,domain,tertiary structure,conserved motif and phosphorylation sites of microalgal lipid droplet proteins.The results showed that LDSP protein of Nannochloropsis was a stable basic hydrophobin without signal peptide.The two transmembrane domains formed amphiphilicα-helix and hydrophobicα-helix,respectively.The secondary structure consisted ofα-helix,extended chain,β-turn and random coil.It had a middle domain of thiamine pyrophosphate,a funnel-shaped tertiary structure,a conserved motif at C-terminus,which has nine phosphorylation sites.Unlike LDSP protein of Nannochloropsis,MLDP protein of Dunaliella pavus and HOGP protein of Haematococcus pluvialis were acidic hydrophilic proteins without transmembrane domain,and the sequences interacting with membrane formed amphiphilicα-helices.They had the rubber elongation factor domain,a dumbbell-shaped tertiary structure,33 and 24 phosphorylation sites respectively.The structural features of MLDP protein of Chlamydomonas reinhardtii were between two types of features.The study indicates that the structures of microalgal lipid droplet proteins are differentiated,which might lead to differences in function.