Department of Immunobiology of Bacteria, University of Lodz, Lodz, Poland.
Adv Clin Exp Med. 2013 Mar-Apr;22(2):165-75.
Proteus sp. strains isolated from patients with urinary tract infection (UTI) are often insensitive to the bactericidal action of normal human serum (NHS) which poses a clinical problem. The swarming phenomenon is an especially important factor in cases of UTIs gained through the ascending route. Both these virulence factors are connected with the cell surface components of bacteria, including lipopolysaccharide (LPS).
The resistance of Proteus bacilli to the bactericidal activity of NHS and the swarming phenomenon were investigated as well as the possible relationships between these virulence factors and the chemical structure of LPS.
The research was carried out on P. penneri and P. vulgaris species. Two preparations of sera were tested with respect to the bactericidal action of NHS. The ability of bacteria to swarm was checked on broth agar plates. The length of the O-specific part of LPS was estimated after poliacrylamide gel electrophoresis (PAGE) and staining with silver nitrate.
Among the 62 tested Proteus strains, over 62% of Proteus vulgaris and 50% of Proteus penneri strains were sensitive to the bactericidal action of NHS. However, the number of resistant strains grew dramatically when serum with blocked complement activation via the alternative pathway was used. From 102 of the Proteus sp. Strains, only few were unable to swarm over the solid surface of the media. The remaining showed diverse ability to translocate.
There was no definite correlation between the chemical structure of the O-specific chains of lipopolysaccharides and sensitivity or resistance of the Proteus sp. strains to NHS. Also, no significant relationships were found between the length or the chemical structure of the O-specific chains of the bacterial LPSs and the swarming phenomenon.
从尿路感染（UTI）患者中分离出的变形杆菌属菌株通常对正常人体血清（NHS）的杀菌作用不敏感，这构成了临床问题。 群集现象是通过上行途径获得尿路感染的一个特别重要的因素。 这些毒力因子都与细菌的细胞表面成分有关，包括脂多糖（LPS）。
研究变形杆菌对 NHS 的杀菌活性的抗性和群集现象，并探讨这些毒力因子与 LPS 化学结构之间的可能关系。
该研究在 P. penneri 和 P. vulgaris 种上进行。 用两种血清制剂检测 NHS 的杀菌作用。 在肉汤琼脂平板上检查细菌的群集能力。 用硝酸银染色后通过聚丙烯酰胺凝胶电泳（PAGE）估计 LPS 的 O-特异性部分的长度。
在 62 株测试的变形杆菌属菌株中，超过 62%的 P. vulgaris 和 50%的 P. penneri 菌株对 NHS 的杀菌作用敏感。 然而，当使用阻断补体通过替代途径激活的血清时，耐药菌株的数量急剧增加。 在 102 株变形杆菌属菌株中，只有少数不能在固体培养基表面群集。 其余的表现出不同程度的迁移能力。
LPS 的 O-特异性链的化学结构与变形杆菌属菌株对 NHS 的敏感性或抗性之间没有明确的相关性。 此外，在 LPS 的 O-特异性链的长度或化学结构与群集现象之间也没有发现显著关系。
