ywbB基因对枯草芽胞杆菌NCD-2菌株菌落形态和芽胞形成的调控  

The colony phenotype and sporulation of Bacillus subtilis strain NCD-2 regulated by ywbB gene

作　　者：郭庆港[1,2] 王培培[1,2] 李社增[1,2] 鹿秀云[1,2] 赵卫松[1,2] 张晓云[1,2] 马平[1,2] 

机构地区：[1]河北省农林科学院植物保护研究所河北省农业有害生物综合防治工程技术研究中心,保定071000 [2]农业部华北北部作物有害生物综合治理重点实验室,保定071000

出　　处：《植物病理学报》2017年第3期340-347,共8页Acta Phytopathologica Sinica

基　　金：公益性行业科研专项(201503109);国家自然科学基金项目(31272085;31572051);河北省自然科学基金项目(C2016301069)

摘　　要：枯草芽胞杆菌NCD-2菌株能有效防治作物土传病害,前期研究证实,ywbB基因正调控NCD-2菌株生物膜形成和根际定殖能力。本研究进一步分析了ywbB基因对NCD-2菌株的生长、菌落形态和芽胞产生等性状的影响。结果表明,同NCD-2野生型菌株相比,突变子ΔywbB降低了在LB和2×SG培养基中的生长速率;在LB或2×SG培养基上,NCD-2菌株可以形成褶皱的菌落形态,而ΔywbB突变子菌落形态平坦,没有褶皱。在2×SG培养基中培养60 h后,NCD-2菌株的芽胞形成率达到68.6%,而ΔywbB突变子的芽胞形成率仅为18.5%。通过RT-qPCR技术分析了ywbB突变后对其上游基因ywbA、下游基因ywbC、芽胞形成相关基因spoIIAA表达量的影响,结果表明,突变ywbB后对ywbA、ywbC基因的表达量没有明显的影响,而ΔywbB突变子中spoIIAA的表达量较NCD-2野生型菌株相比显著降低。Bacillus subtilis strain NCD-2 is an excellent biocontrol agent for suppressing against plant soil-borne diseases. Previous study indicated that the ywbB positively regulated the biofilm formation and root colonization of strain NCD-2. In this study, the bacteria growth curve, the colony phenotype, and the sporulation were compared between strain NCD-2 wild type and the mutant strain ΔywbB. Results revealed that the growth of the mutant strain ΔywbB was decreased both in LB medium and 2×SG medium. The NCD-2 wild type strain could form wrinkled colonies in LB or 2×SG medium, but the mutant strain ΔywbB only formed flat colonies in LB or 2×SG medium. After cultured 60 h in 2×SG medium, the NCD-2 wild type strain could produce 68.8% heat-resistant spores, but the mutant strain ΔywbB only produced 18.5% heat-resistant spores. RT-qPCR analysis revealed that knockout of ywbB did not alter the expression level of ywbB upstream gene ywbA and downstream gene ywbC, but significantly decreased the expression level of sporulation related gene spoIIAA.

关 键 词：枯草芽胞杆菌 生物膜 菌落形态 芽胞 

分 类 号：S476[农业科学—农业昆虫与害虫防治]