一株具有纤维素酶活性细菌菌株的鉴定及其生物学活性  

Identification of bacteria strain with cellulase activity and its biological activity

作　　者：丁泽力 周挺[2] 顾钢[2] 季梦婷 李春英[2] 蔡学清[1] DING Zeli;ZHOU Ting;GU Gang;JI Mengting;LI Chunying;CAI Xueqing(College of Plant Protection,Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China;Institute of Tobacco Science,Fujian Provincial Tobacco Company,Fuzhou,Fujian 350003,China)

机构地区：[1]福建农林大学植物保护学院,福建福州350002 [2]福建省烟草公司烟草科学研究所,福建福州350003

出　　处：《亚热带农业研究》2023年第3期202-208,共7页Subtropical Agriculture Research

基　　金：福建省引导性项目“防控作物青枯病的新型微生物制剂的研发及应用关键技术研究”(2022N0004);中国烟草总公司科技计划项目“基于稻烟轮作的武夷丘陵生态区绿色防控综合治理技术研究与应用”[110202201028(LS-12)];中国烟草总公司福建省公司科技计划项目“烟田生境植物浸提液对烟草土传病害的防控效应研究”(2022350000240061)。

摘　　要：[目的]筛选具有纤维素酶活性的菌株,探究其对杂草的腐解和青枯菌的抑菌作用,为作物青枯病防治和杂草防除提供新思路。[方法]采用点滴法从162株叶际细菌中筛选具有纤维素酶活性的细菌,测定其对作物青枯菌(Ralstonia pseudosolanacearum)的拮抗作用及对空心莲子草(Alternanthera philoxeroides)和辣蓼草(Polygonum hydropiper)的腐解作用。进一步通过形态学特征、生理生化测定和16S rDNA基因序列分析等明确其分类地位。[结果]从162株叶际细菌中筛选出15株具有纤维素酶活性的菌株,占比9.26%,其中H16菌株的纤维素酶活性最强,水解圈半径为3 mm,且该菌株的菌体和代谢产物都具有纤维素酶活性。在NA培养基平板上,H16菌株菌落为圆形、红色;菌体短杆状,端圆,侧生鞭毛4~8根。H16菌株可利用海藻糖、麦芽糖、蔗糖、山梨醇和甘露醇等;硝酸钾还原反应、淀粉水解、过氧化氢酶反应、氧化酶反应等为阳性。16S rDNA序列分析结果显示,H16菌株与嗜线虫沙雷氏菌(Serratia nematodiphila)聚为一支,将其鉴定为嗜线虫沙雷氏菌(S.nematodiphila)。H16菌株对烟草青枯菌和辣椒青枯菌具有较好的抑菌作用,抑菌圈半径为1.5~4.0 mm;该菌株可快速腐解空心莲子草和辣蓼草,用菌悬液浸泡3 d,2种杂草约腐解40%~80%,浸泡4~5 d全部腐解,而无菌水处理则需10 d才全部腐解。[结论]筛选获得的沙雷氏菌H16菌株具有纤维素酶活性,能快速腐解空心莲子草和辣蓼草,对青枯病菌有拮抗作用,具有潜在应用前景。[Purpose]Bacteria with cellulase activity was screened and analyzed for its decomposed effect on weed and bacteriostasis on Ralstonia pseudosolanacearum,so as to provide a new perspective for effective control of crop bacterial wilt and weed.[Method]A total of 162 strains of phyllosphere bacteria were screened for cellulase activity by hanging drop culture method,and the strains with the highest cellulase activity were determined for antagonism against R.pseudosolanacearum and biodegradation capacity on Alternanthera philoxeroides and Polygonum hydropiper.Furthermore,its taxonomic status was determined based on morphological characteristics,physiological and biochemical properties,and 16S rDNA sequence analysis.[Result]Up to 15 strains with cellulose activity were screened,accounting for 9.26%of the 162 phyllosphere bacterial strains tested.Strain H16 had the greatest cellulose activity with a hydrolysis circle radius of 3 mm,whose metabolites and bacterial cells both showed cellulase activity.Its bacterial colony was round and red on NA medium,and its bacterial cells were rod-shaped and had 4-8 lateral flagella.Strain H16 could utilize trehalose,maltose,sucrose,sorbitol and mannitol;it was capable of reducing nitrate and hydrolyzing starch,and had catalase and oxidase activities.16S rDNA sequence analysis further revealed its cluster with Serratia nematodiphila,and thus was identified as S.nematodiphila.Strain H16 showed better antagonistic effect on R.pseudosolanacearum of tobacco and pepper with the radius of bacteriostatic zone being 1.5-4.0 mm.Moreover,the strain could accelerate the decomposition of Alternanthera philoxeroides and Polygonum hydropiper,which was degraded to 40%-80%of the original within 3 d,and completely decomposed within 4-5 d by bacterial suspension treatment.Nevertheless,it took 10 d for the complete degradation by water.[Conclusion]Serratia strain H16 demonstrated good cellulase activity and antibacterial effect on R.pseudosolanacearum,and accelerated the degradation of A.philoxeroides

关 键 词：纤维素酶 青枯病菌 空心莲子草 辣蓼草 嗜线虫沙雷氏菌 

分 类 号：Q939[生物学—微生物学]