动物溶菌酶基因的研究进展

ttttt目的ttttt溶菌酶是一种由动物产生的抗微生物酶，构成动物体先天免疫系统的一部分，在反刍动物的皱胃中还具有消化功能。迄今，普通牛溶菌酶C基因家族的分子遗传特征已被深入解析，但有关水牛溶菌酶C的研究报道较少。ttttttttttttt方法ttttt采用PCR产物直接测序技术，对槟榔江水牛胃型溶菌酶C基因编码区进行了分段扩增测序、序列组装和开放阅读框的确定，并结合已发表的其他牛科物种同源序列进行了生物信息学分析。ttttttttttttt结果ttttt序列分析表明：水牛胃型溶菌酶C基因编码区长444 bp，编码1个由147个氨基酸残基组成的多肽，包含1个N端信号肽和1段由129个氨基酸组成的成熟肽。水牛胃型溶菌酶C成熟肽分子量为14.41 ku，等电点为6.32，含有1个alpha-lactalbumin/lysozyme C保守结构域(19~145AA)，不含有跨膜结构域，为亲水蛋白，在胞外发挥生物功能；在三维结构上与普通牛的溶菌酶模板(2z2f.1.A)有99.22%的一致性；在基于氨基酸序列构建的系统树上，水牛与普通牛、瘤牛、野牦牛和野牛聚在一起，且有较高的支持率(88%)。ttttttttttttt结论ttttt槟榔江水牛与其他牛科物种的胃型溶菌酶具有相似的功能。tttt

Evolution of the bovine lysozyme gene family: changes in gene expression and reversion of function

tttttPurposetttttLysozyme is an antibacterial enzyme produced by animals that forms part of the innate immune system. It also has digestive function in the abomasum of ruminants. Up to now, the lysozyme C gene family of cattle has been characterized at the molecular level deeply, but the studies on the lysozyme C gene in water buffalo are few.tttttttttttttMethodstttttIn this study, the sequences of Binglangjiang buffalo gastric lysozyme C gene were amplified and sequenced by using PCR product direct sequencing, then the sequences were assembled and the open reading frame was determined. Combined with published homologous sequences of other bovine species together, the data obtained was analyzed using bioinformatics method.tttttttttttttResultstttttSequence analysis revealed that the CDS of Binglangjiang buffalo gastric lysozyme C gene encodes a peptide of 147 amino acid residues which was presumed to have a 18 AA signal peptide at N-terminus signal peptide and a 129 AA mature peptide. The mature peptide with a deduced molecular weight of 14.41 ku and a PI of 6.32 is a hydrophilic protein without transmembrane domains and exert its function in the outside plasma membrane with high reliability. In addition, the mature peptide has a conserved domain of Alpha-lactalbumin/lysozyme C (19-145AA) which belongs to lysozyme-like superfamily, and its 3-D structure has 99.22% identical to the lysozyme template of cattle (2z2f.1.A). Phylogeny analysis based on the sequence of lysozyme C showed that water buffalo gather together with Bos taurus, Bos indicus, Bos mutus, Bison bison bison.ttttttttttttttttttConclusiontttttThe results of this study reveal that the stomach lysozyme of Binglangjiang buffalo has similar function to that of other bovine species.tttt