德国小蠊肠道菌BGI-17的鉴定及抗真菌研究  

Identification and anti-fungal activity of intestinal bacterium BGI-17 from Blattella germanica

作　　者：张凡[1] 

机构地区：[1]山东师范大学生命科学学院,山东济南250014

出　　处：《中国媒介生物学及控制杂志》2012年第1期39-41,共3页Chinese Journal of Vector Biology and Control

基　　金：山东省教育厅科技发展计划项目(J11LC13;J07YG02);山东省中青年科学家科研奖励基金资助项目(2007BS02014)~~

摘　　要：目的对分离自德国小蠊肠道的细菌BGI-17进行鉴定,并研究其对昆虫致病真菌的抑制效果,为探明德国小蠊肠道菌群的组成及其与虫体间的关系打下基础。方法利用PCR扩增该菌16S rDNA序列,根据测序结果构建系统发育树,结合形态及生理生化特征对BGI-17进行鉴定;利用平板抑制法测定该菌对白僵菌的抑菌效果,并观察该菌对真菌菌丝生长的影响。结果该菌短杆状,周生鞭毛,革兰染色、芽孢染色、接触酶为阳性,初步鉴定为芽孢杆菌属,基于16S rDNA基因序列构建的进化树显示,该菌与萎缩芽孢杆菌相似度达到99%,两者所构建的系统发育树处于同一个分支;该菌对白僵菌生长有明显抑制效果,真菌菌丝出现病态的空泡状膨大,导致原生质外泄和菌丝断裂。结论德国小蠊肠道菌BGI-17属萎缩芽孢杆菌,可拮抗昆虫致病真菌,可能有助于德国小蠊抵御病原真菌的侵染。Objective To identify an intestinal bacterium BGI-17 isolated from German cockroaches（Blattella germanica） and to study its activity of anti-pathogenic fungi so as to clarify the composition and relationship of the intestinal flora in B.germanica.Methods The strain BGI-17 was identified according to the morphology and physiological and biochemical characteristics,and the phylogenetic tree was generated based on the sequence of 16S rDNA for molecular identification.The test for anti-Beauveria bassiana was conducted using the plate inhibition method and the growth of fungi was observed.Results The short,rod-shaped BGI-17 was positive for flagellum,Gram stain,spore stain and catalase.The 16S rDNA sequencing of BGI-17 showed that it shared 99% similarity with the published sequence of Bacillus atrophaeus strain,and both sequences constituted a branch in phylogenetic tree.The BGI-17 inhibited the growth of B.bassiana obviously and the fungal mycelium showed sick vacuolar enlargement,leading to leakage and mycelia protoplast rupture.Conclusion The BGI-17 was B.atrophaeus and it showed strong anti-insect pathogenic fungal activity that might contribute to withstanding the infection of pathogenic fungi.

关 键 词：德国小蠊 肠道细菌 16S RDNA 鉴定 萎缩芽孢杆菌 抗真菌 

分 类 号：R384[医药卫生—医学寄生虫学]