人等所有后生动物体内微生物数量多、种类复杂,给人们的研究带来了很多的困难,建立无菌和悉菌的动物模型则是当前急迫之需,无菌果蝇模型日益受到重视.本实验优化无菌果蝇模型,发现威露士可以协助次氯酸和乙醇消毒,对大肠杆菌、金黄色葡萄球菌和白色念珠菌杀灭效率为99.999%,提高表面消毒能力,卵存活率从50%左右提高到67.3%.从而高效率地建立果蝇悉菌模型.在此基础上研究酵母对该模型的影响,结果发现酵母能显著地促进无菌果蝇的生长与发育.在营养条件匮乏(0.5%酵母)情况下,常规饲养果蝇蛹和成虫羽化时间分别为6.0 d和11.7 d;无菌果蝇蛹和成虫羽化时间分别为7.8 d和18.9 d,说明共生微生物可以促进果蝇的发育.本研究优化了无菌果蝇操作过程,为实验室建立悉生果蝇模型提供了便利,有利于研究宿主与微生物之间相互作用.
All metazoan including human inhabit a large number of microorganisms. The complexity and diversity of bacterial community restricts us to explore the underlying mechanism of the relationship of microbes and hosts. Therefore,it is necessary to use germ-free and/or gnotobiotic animal model in research,and fruit fly Drosophila acted as this excellent model, due to its amenability to genetic study, lower microbiota complexity,and the easiness in manipulating germ free flies. At first,we optimized the protocol of germ-free Drosophila model,and found that Walch solution cooperated with chloride and ethanol solution to remove the microbes on the surface of eggs,the eradication efficiency to Escherichia coli,Staphylococcus aureus and Candida albicans was 99. 999%,and efficiently generated germ-free Drosophila model,eggs survival rate increased from about 50% to 67. 3%. Based on this model,we investigated the potential roles of yeast on hosts,and found that yeasts were required to promote the development of fruit flies in a dose-dependent manner. In the condition of poor nutrition( 0. 5% yeast) cases,conventional breeding of Drosophila pupae and eclosion time were 6. 9 d and 11. 7 d. sterile Drosophila pupae and eclosion time were delayed to 7. 8 d and 18. 9 d. Indicated symbiotic microbes were required to promote the development of Drosophila. In conclusion,the optimized protocol of germ-free Drosophila model contributed to our knowledge of interaction of microbes and hosts.