昆虫病原斯氏线虫SY-5对重组Cip晶体蛋白的营养利用（英文稿）

【目的】初生型Photorhabdus luminescens细菌产生两种胞内晶体蛋白CipA和CipB,为其共生的昆虫病原异小杆线虫提供营养。探索非共生的斯氏线虫对Cip蛋白的营养利用情况。【方法】在已构建重组Cip蛋白大肠杆菌表达体系的基础上,建立重组菌细胞与无菌斯氏SY-5线虫共培养系统,检测线虫的生长发育情况。【结果】Cip蛋白对目标线虫生长有显著支持作用:发育为成虫的比例达到65%-82%,雌虫的怀卵率为80%-95%,平均怀卵量为30-50粒,并显著降低各虫态的死亡率。【结论】Cip蛋白不仅为共生的异小杆线虫提供营养,亦能为斯氏线虫所利用。

Nutrition utilization of entomopathogenic nematode Steinernema sp. SY-5 on recombinant crystalline inclusion proteins

[Objective] Phase I cells of Photorhabdus luminescens bacteria, symbiotically associated with entomopathogenic Heterorhabditis nematode, produce two types of intracellular crystalline inclusions, CipA and CipB, to support the symbiont. This study aimed to investigate the possible influence of Cip proteins on non-symbiotic Steinernema nematode. [Methods] Based on constructed Escherichia coli expression system of Cip proteins, co-culture system of recombinant E. coli bacteria and Steinernema sp. SY-5 nematode was set up. [Results] The Cip proteins significantly promoted the development of SY-5 nematode to make high adult rate of 65%?82%, gravid rate of 80%?95%, 30?50 eggs per nematode, and low mortalities. [Conclusion] As the nutrient reserves for Heterorhabditis nematode, Cip proteins can be accepted and utilized by Steinernema nematode. The progress on these proteins will provide insights into the mechanisms governing bacteria-nematode symbiosis.