副溶血性弧菌K抗原检测实验条件优化

目的优化副溶血性弧菌K抗原检测的实验条件。方法通过调整菌悬液的浓度、选择基础实验材料和控制反应的温度3个方面的因素,对已知血清型的副溶血性弧菌进行血清学实验。结果当反应温度为37℃时,以90 mm无菌培养皿为基础耗材、20 mg/300μL浓度的菌悬液更容易快捷地观察到凝集现象,并且凝集颗粒较多,较大。结论基于本研究优化后的实验条件,使得凝集结果判读更加容易,实验操作更为简便、安全,且提高了血清学实验的效率。     

Bacterial Molecular Signals in the Sinorhizobium fredii-Soybean Symbiosis

Sinorhizobium (Ensifer) fredii (S. fredii) is a rhizobial species exhibiting a remarkably broad nodulation host-range. Thus, S. fredii is able to effectively nodulate dozens of different legumes, including plants forming determinate nodules, such as the important crops soybean and cowpea, and plants forming indeterminate nodules, such as Glycyrrhiza uralensis and pigeon-pea. This capacity of adaptation to different symbioses makes the study of the molecular signals produced by S. fredii strains of increasing interest since it allows the analysis of their symbiotic role in different types of nodule. In this review, we analyze in depth different S. fredii molecules that act as signals in symbiosis, including nodulation factors, different surface polysaccharides (exopolysaccharides, lipopolysaccharides, cyclic glucans, and K-antigen capsular polysaccharides), and effectors delivered to the interior of the host cells through a symbiotic type 3 secretion system.