Molecular analysis of pathogen in periodontopathic bacteria

成人牙周炎是一种感染性疾病，可导致牙齿脱落。它会引起咀嚼问题，最终导致牙周病患者的生活质量下降。由于许多试图澄清疾病的病原体，这些病原体发挥其作用的分子机制尚不清楚。为了阐明潜在牙周病细菌的致病机制，我们试图对来自放线菌行动杆菌、去forsydibacteriodesforsydius和密螺旋体denticola病原体的编码基因进行鉴定。我们测定了放线菌的菌毛基因（fap），以表征其在定植中的作用。这种微生物的毛状菌在传代到固体培养基上时失去了毛状菌。W发现fap基因的表达在非纤维化菌株（Microbiol）中降低。中华病理学杂志，1997,23:63-69)。已知蛋白酶对宿主组织具有细胞毒性作用。我们测定了一种难以在合成培养基中获得足够生长的酵母蛋白酶基因（prH）的序列。蛋白酶的分子质量为47,873，PrtH具有溶血活性（影响）。中国生物医学工程学报，2009,35(5):588 - 591。一些报道指出，全身化疗失败是由于幽门螺杆菌在口腔内定植引起的。研究口腔微生物对幽门螺旋杆菌的拮抗作用。H.pylon与P.gingivalis和F.nucreatum聚在一起。另一方面，几种口腔细菌抑制hpylon （FEMS）微生物的生长。生态学报，1997,15:355-361)。利用野生型菌株和单基因缺陷突变体进行致病性评价是评价病原菌致病性最有效的方法。我们构建了齿状霉脯氨酸-苯丙氨酸特异性蛋白酶（dentilisin）的基因敲除突变体，并对其进行了表征。该微生物的表面疏水性显著下降，脓肿形成能力下降。此外，我们还发现牙釉质蛋白与外鞘蛋白的组织有关。这些结果表明牙釉质素直接对宿主组织产生细胞毒作用（J.Bacteriol.）。[j] .农业工程学报，2009,29(3):387 - 398。少

Adult periodontitis was Infectious disease and it induce tooth loss. It cause a mastication problem and finally induce poor quality of life in patients with periodontal disease. As many attempts to clarify pathogen of the disease have been performed, the molecular mechanisms by which these pathogens exert their effects are poorly understood. To clarify the pathogenic mechanism of potential periodontopathic bacteria, we tried to characterize genes encoding pathogens from Actionbacillus actinomycetemcomitans, Bacteriodesforsydius and Treponema denticola.We determined the fimbriae gene (fap) of A.actinomycetemcomitans to characterize its role in colonization. The fimbriated strain of this microorganism lost fimbriae upon passaging onto solid medium. W found that expression of the fap gene was decreased in non-fimbriated strain (Microbiol. Pathog. 1997, 23 : 63-69).Proteases were known to exert a cytotoxic effects to host tissue. We detennined the sequence of a protease gene (prH) of B.for … More sythus which is difficult to get enough growth in synthetic medium for a characterization. A molecular mass of the protease is 47,873 and the PrtH possessed hemolytic activity (Imfect. Immun. 1997, 65 : 4888-4891).Several reports indicated the systemic chemotherapy failure was caused by colonization of Helicobcterpylori in oral cavity. We evaluated the antagonistic effects between oral microorganism and H.pylon. H.pylon was coaggregated with P.gingivalis and F.nucreatum. On the other hand, several oral bacteria inhibits growth of H.pylon (FEMS Microbial. Lett. 1997, 152 : 355-361).Evaluation of a pathogenicity using wild type strain and single gene deficient mutant is the most effective way to evaluate its pathogenicity. We constructed a knockout mutant of the prolyl-phenylalanine specific protease (dentilisin) in T denticola and characterized the mutant. Surface hydrophobicity of this microorganism decreased dramatically and ability of abscess formation decreased in the mutant. In addition, we found that dentilisin is associated with organization of outer sheath protein. These results indicated that dentilisin exert a cytotoxic effects to host tissue directly (J.Bacteriol. 1998, 180 : 3837-38449). Less