Cariogenicity of Denture Plaque

值得注意的是，龋齿的发生不仅取决于末端的pH值，还取决于其他几个因素，包括细菌粘附或定植牙齿表面的能力。在这个项目中，我们发现白色念珠菌对完整的和变性的I型胶原蛋白的粘附力明显大于口腔细菌和其他种类的念珠菌。我们还发现白色念珠菌在有牛血清白蛋白的培养基中培养时，能降解完整的海绵胶原蛋白。细胞溶胶原的活动相关联的C.albicans量化通过测量合成溶胶原的肽的降解2-furanacryloyl-Leu-Gly-Pro-Ala (FALGPA),这是一个特定的胶原酶的底物。与变形链球菌和放线菌相比，白色念珠菌细胞相关的胶原溶解活性相对较低。虽然与乳酸菌的含量几乎相同。在有牛血清白蛋白的培养基中培养的细胞具有增强的胶原溶解活性，在有EDTA的培养基中培养的细胞具有抑制的活性，而丝氨酸蛋白酶抑制剂（APMSF）和天冬氨酸蛋白酶抑制剂（Pepstatin A）没有抑制这种活性。明胶酶谱法对白色念珠菌条件培养基进行分析，发现116k和150kDa条带。这些条带在煮沸后消失，但EDTA处理后没有影响。这些结果表明，白色念珠菌产生多种胶原溶解酶，可能是牙根龋发病的一个因素。

It is noteworthy that the cariogenicity depends not only on the terminal pH, but also on several other factors, including the ability of the organism to adhere or colonize the tooth surface. At this project, we found that the adhesion of C.albicans to intact and denatured type I collagen was significantly greater than those of oral bacteria and other species of Candida.Also we found that C.albicans degrade intact collagen sponge when C.albicans cultured in the presence of bovine serum albumin in culture medium.Cell associated collagenolytic activity of C.albicans was quantitated by measuring the degradation of synthetic collagenolytic peptide 2-furanacryloyl-Leu-Gly-Pro-Ala (FALGPA), which is a specific substrate for collagenase. Cell associated collagenolytic activity of Candida albicans was relatively lower than that produced by Streptococcus mutans or Actinomyces. Although it was almost same level as that of lactobacillus.. This collagenolytic activity was enhanced by the cells cultured in the presence of bovine serum albumin in culture medium and this activity was inhibited in the presence of EDTA, but not by the serine proteinase inhibitor (APMSF) and the aspartyl proteinase inhibitor (Pepstatin A).Analyze of conditioned medium of C.albicans by gelatin zymography shows 116k and 150kDa bands. These bands were disappear by boiling of the sample, though no effect by the treatment with EDTA.These results indicate that C.albicans produces several collagenolytic enzymes and which may be a factor involved in pathogenesis of root caries.