细胞壁降解酶在球刺盘孢侵染过程中的作用  

The role of cell wall-degrading enzymes of Colletotrichum coccodes during its infection

作　　者：金梦军 杨成德 李统华 OSEI Richard 蔡锋锋 马婷 JIN Mengjun;YANG Chengde;LI Tonghua;OSEI Richard;CAI Fengfeng;MA Ting(Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province,College of Plant Protection,Gansu Agricultural University,Lanzhou 730070,China)

机构地区：[1]甘肃省农作物病虫害生物防治工程实验室,甘肃农业大学植物保护学院,兰州730070

出　　处：《植物保护》2024年第3期88-98,110,共12页Plant Protection

基　　金：国家自然科学基金(32360657);国家现代农业产业技术体系(CARS-09-P10);2021年度甘肃省优秀研究生“创新之星”项目(2021CXZX-380)。

摘　　要：为明确球刺盘孢Colletotrichum coccodes产生的细胞壁降解酶(CWDEs)在其侵染马铃薯过程中的作用,本文对球刺盘孢离体和活体条件下产生的CWDEs种类及活性进行检测,并通过RT-qPCR测定了球刺盘孢侵染过程中多聚半乳糖醛酸酶(PG)基因的表达情况。通过定性测定发现,球刺盘孢能够产生果胶酶、纤维素酶和蛋白酶;定量测定发现,球刺盘孢可产生羧甲基纤维素酶(Cx)、β-葡萄糖苷酶(β-Glu)、PG和聚甲基半乳糖醛酸酶(PMG)。在活体条件下,球刺盘孢可在马铃薯茎秆内产生PG、PMG和多聚半乳糖醛酸反式消除酶(PGTE),且酶活分别于接种后48、72 h和144 h达到最大值,分别为26.50、77.61 U/mL和0.16 U/mg。分别将羧甲基纤维素钠和果胶诱导后的酶液接种至马铃薯茎秆可引起植物组织浸腐,与球刺盘孢引起的典型症状相似。除此之外,球刺盘孢的4个PGs基因均在其侵染后24 h和48 h显著共上调表达。综上所述,该研究结果表明,果胶酶在球刺盘孢致病过程中发挥重要作用。To determine the function of cell wall-degrading enzymes(CWDEs)secreted by Colletotrichum coccodes during infecting potato stems,the types and activities of CWDEs secreted by C.coccodes both in vivo and in vitro were investigated,the gene expression levels of four polygalacturonases(PG)of C.coccodes were also assessed using RT-qPCR.The qualitative measurement results indicated that C.coccodes secretes pectinase,cellulase,and protease on detection plates in vitro,and the qualitative determination results demonstrated that it secretes carboxymethyl cellulase(Cx),β-glucosidase(β-Glu),polygalacturonase(PG),and polymethyl-galacturonase(PMG)on detection medium in vitro.In addition,C.coccodes produces PG,PMG and polygalacturonic acid trans-eliminase(PGTE)during its infection to potato stems in vivo,with peak activities of 26.50,77.61 U/mL and 0.16 U/mg 48 h,72 h and 144 h post-inoculation,respectively.Inoculating crude enzymes induced by sodium carboxymethylcellulose and pectin onto potato stems could cause potato stem rotting similar to the typical symptoms caused by C.coccodes on potato stems.Moreover,four PGs of C.coccodes showed significantly upregulated co-expression 24 h and 48 h post-inoculation.Collectively,these data demonstrated the important role of pectinase in the pathogenic process of C.coccodes.

关 键 词：球刺盘孢 马铃薯 细胞壁降解酶 多聚半乳糖醛酸酶 

分 类 号：Q939.9[生物学—微生物学]