基于全基因组序列的尖孢镰刀菌分泌蛋白预测及其特征分析

尖孢镰刀菌是一种以土壤习居为主要特征的植物病原菌,广泛分布于世界各地,且寄主广泛,能引起豆科、茄科、葫芦科等科100多种植物根腐、茎腐、茎基腐等病害,严重时造成植株萎蔫死亡,严重影响着植物的产量和品质.同时,目前生产上对于该菌的防治多使用甲霜灵·锰锌、多菌灵、百菌清等化学药剂,然而,防治效果不佳,急需开发针对该菌新的作用靶标的药剂.前人已经明确植物病原真菌分泌蛋白在侵染、操控植物等过程中发挥着重要功能,然而,学术界尚未见有关该菌中分泌蛋白的报道.本研究以尖孢镰刀菌菌株(Fusarium oxysporumf.sp.lycopersici 4287)的蛋白序列为基础数据,以分泌蛋白所具有的N-端含有信号肽、不含有跨膜结构域、没有GPI锚定位点、将蛋白分泌在胞外4大特征为依据,利用生物信息学在线分析程序明确该菌中含有778个分泌蛋白,并对上述蛋白开展特征分析,明确上述蛋白的氨基酸长度主要集中在101～400aa、氨基酸组成中以G,T,S,A较多,信号肽长度主要集中在16～21aa、信号肽氨基酸组成中以P,S,A,T,G较多,信号肽切割位点为T-X-T类型.为今后进一步开展尖孢镰刀菌的分泌蛋白功能解析和开发新型药剂靶标提供了重要的理论基础.

Prediction of secreted proteins of Fusarium oxysporum based on whole genome sequence

Fusarium oxysporumis a plant pathogen with soil habits as the main feature.It is widely distributed all over the world and has a wide range of hosts.It can cause more than 100 kinds of root rot and stem rot of legumes,Solanaceae and Cucurbitaceae.In some cases,even the plants will die,seriously affecting the yield and quality of the plants.At the same time,at present,chemical agents such as metalaxyl,manganese zinc,carbendazim,and chlorothalonil are often used for the prevention and treatment of the fungus.However,the control effect is not good,and it is urgent to develop a drug for the new target of the fungus.Predecessors have already made clear that the secret proteins of plant pathogenic fungi play important roles in the process of infecting and manipulating plants.However,there has been no report on secreted proteins in this bacterium.In this study,based on the protein sequence of Fusarium oxysporumf.sp.lycopersici 4287,the secreted protein has a N-terminal signal peptide,no transmembrane domain,and no GPI anchor site.Based on the four major characteristics of protein secretion in the extracellular,the bioinformatics online analysis program was used to identify 778 secreted proteins in the fungus,and the characteristics of the above proteins were analyzed.The amino acid length of the above proteins was mainly concentrated in 101.-400 aa,amino acid composition with G,T,S,A,signal peptide length is mainly concentrated in 16～21 aa,signal peptide amino acid composition,especially P,S,A,T,G,signal The peptide cleavage site is of the TXT type.This study provides an important theoretical basis for the further analysis of the secreted protein function of F.oxysporumand the development of new pharmaceutical targets.