嗜水气单胞菌中类组蛋白HupB生理功能的研究

【目的】DNA结合蛋白HU蛋白是一类组蛋白样蛋白,其参与细菌DNA的重组与修复,在细菌的转录调控中发挥重要作用,但目前该蛋白对细菌生理功能的影响尚不完全清楚。为了更好地理解HU蛋白,本研究探讨HupB的生理功能。【方法】以嗜水气单胞菌(Aeromonas hydrophila)ATCC7966为研究材料,利用同源重组技术构建编码HU蛋白β亚基的hupB基因缺失菌株,并对其常见生理表型进行测定。【结果】hupB基因缺失菌株的溶血性、胞外蛋白酶活性和运动性均显著增强,而生物被膜形成能力显著下降,并且ΔhupB::hupB菌株中生物被膜形成能力恢复。进一步利用基于label-free的定量蛋白质组学技术比较了野生株和ΔhupB突变株的差异表达蛋白,发现235个蛋白表达上升,224个蛋白表达下降。生物信息学分析显示hupB敲除后导致蛋白质翻译、生物被膜生成以及信号转导等多个生物过程相关蛋白表达发生变化。【结论】研究结果表明嗜水气单胞菌HupB蛋白能显著影响细菌生物被膜形成能力,以上研究为更好地探究嗜水气单胞菌HupB蛋白对细菌生理功能的调控机制提供理论基础。

Mycobacterium tuberculosis in the aorta of a patient with takayasu’s arteritis. extra pulmonary tuberculosis

Takayasu’s arteritis (TA), of unknown etiology, has been related with Mycobacterium tuberculosis infection. The published cases are controversial. A 29- year-old man died, prolapse of the aortic valve and unspecific arteritis were demonstrated at necropsy. Our objective was to search in the fresh aortic tissues, the infectious agent of tuberculosis through culture, as well as by performing histopathology and searching by the molecular study, sequences of genes associated to micobacteria and Ziehl’s stain. Results. The bacillus of tuberculosis was observed by the Ziehl’s stain and the sequences of insertion IS6110 gene were identified. Our findings support the relation of TA with possible tuberculosis infection.Conclusion. The possibility that Takayasu’s arteritis is an extra pulmonary tu-berculosis must be explored.