Investigation of the secretion system of pathogenic proteinases in Porphyromonas gingivalis and study of the way to control the system

我们研究了牙周病病原体牙龈卟啉单胞菌致病蛋白酶/粘附素的分泌系统。这种分泌依赖于蛋白质分泌系统，即Por分泌系统（PorSS）。我们分离了几个牙龈菌蛋白酶分泌缺陷型突变体，发现其中两个是在一个双组分系统，这是一个原核细胞的信号转导系统的缺陷。PorY是一种传感器组氨酸激酶，PorX充当反应调节剂。重组PorY被自磷酸化，并将PorY上的磷酰基转移到PorX上。表面等离子体共振分析也揭示了PorY和PorX之间的相互作用。PorSS组分蛋白的基因表达也受ECF sigma因子之一PGN 0274的调节，而不依赖于PorY-PorX系统，这表明该分泌系统受多种调节机制的调节。

We investigated the secretion system of pathogenic proteinases/ adhesins in periodontopathogen Porphyromonas gingivalis. The secretion depends on a protein secretion system, Por secretion system(PorSS). We isolated several gingipain secretion-deficient mutants and found that two of them were deficient in a two-component system, which is a prokaryotic signal transduction system. PorY is a sensor histidine kinase and PorX acts as a response regulator. The recombinant PorY was autophosphorylated and the phosphoryl group on PorY was transferred to PorX. The interaction between PorY and PorX was also revealed by Surface plasmon resonance analysis. Gene expression of component proteins of the PorSS was also regulated by one of ECF sigma factors, PGN0274, independently of PorY-PorX system, suggesting that the secretion system is regulated by multiple regulatory mechanisms.