天祝白牦牛与黄牛NGB蛋白三级结构比较分析

通过比较天祝白牦牛(Bos grunniens)与黄牛(Bos taurus)NGB蛋白三级结构,分析天祝白牦牛NGB蛋白氨基酸位点突变对其三级结构的影响.利用生物信息学在线分析网站及软件对天祝白牦牛和黄牛NGB蛋白的同源性、系统发育进化、三级结构进行比较分析.结果显示,天祝白牦牛NGB蛋白进化趋于保守,83号位点为未...

Comparative analysis of three-dimensional structure of neuroglobin protein in Tianzhu white yak and cattle

The study compared the three-dimensional structures of neuroglobin(NGB)protein in Tianzhu white yak(Bos grunniens)and cattle(Bos taurus),and analyzed the effect of amino acid site mutation of NGB protein in Tianzhu white yak on its three-dimensional structure.The bioinformatics online analysis website and software were used to compare and analyze the homology,phylogenetic evolution,and three-dimensional structure of NGB protein in Tianzhu white yak and yellow cattle.Results showed that the evolution of Tianzhu white yak NGB protein tended to be conservative,where the 83 rd site of Tianzhu white yak NGB protein was an unknown mutation and the 97 rd site was a conservative substitution.Three-dimensional structure analysis revealed that the mutation of the 83 rd site caused the mutation of the NGB protein Ser to Pro.The main reason was that the R side chain was mutated from alcohol hydroxy group to four carbon ring,and the overall side chain structure changed,so the 83 rd site changed from α-helices to random coil.The mutation located between E and F chains,and the spacing between the E and F chains changed from 11.79? to 8.21?,resulting in the distance from the center of the porphyrin ring to the distal His 64 changed from 2.17? to 2.10?.The mutation of the 97 th site caused the NGB protein Arg to be mutated to Gln.It was mainly because the R side chain was mutated from nitrogen atom to oxygen atom and was linked to the carbon atom through a double bond,and the overall side chain structure was not changed.Therefore,the 97th site after mutation remained to beα-helices,the mutated group pointed to the hydrophilic phase,and the carboxy terminus was linked to the proximal His 96 site,resulting in the distance between the His 96 and the porphyrin ring center changed from 1.98? to 2.00?.After comparison,the two mutations in Tianzhu white yak did not occur in the core functional region of NGB protein,which had no effect on the function of NGB protein.The mutations caused the change of R side chain group,which may have effects on the stability,flexibility,and solubility of NGB protein.The distance between core His 64,His 96,and porphyrin ring center changed,indicating that the mutation is likely to affect the heme exogenous ligand binding.