Self Defence Mechanism of Porphyromonas gingivalis and Its Periodontopathogenicity

牙龈卟啉单胞菌（P.G.）通常在无代谢BHI-肉汤中消费arginine，建议这种氨基酸可能是主要的能量来源。精氨酸carboxyptide酶，是一种可以参与释放肽中的精氨酸、从P. g的细胞系中分离和纯化的酶的酶。cells。SDS-PAGE的酶与2-巯基乙醇揭示了42、33和32 kDa的三大波段的存在，其中30个氨基酸序列在NHYD 22-终端是明显的，YEWNAYPTYEAYISMMEEFQT-KYPSLXTXXS。开放阅读框架（ORF），从含有未完成的数据库上的N末端氨基酸的核苷酸序列中被怀疑为对应的N末端氨基酸。W83基因组，显示包括锌结合区域签名，建议锌碳蛋白酶。如果要从肽的内部释放精氨酸，则可以确定为碳基蛋白酶的外型，可以将精氨酸与类似于酶（半胱氨酸蛋白酶）的酶结合起来，则可以确定为该细菌的主要期间。在与精氨酸消费和能源生产的关系中，P.G.细胞提取物。用于精氨酸脱氨酶途径和腺苷三磷酸盐生产的明显的诱导酶活性。Besides arginine catabolism，P.g.以热休克蛋白为例，并在热休克后增加合成，建议物理学的作用来保护他们自己的细胞。这些结果显示了P.G.。通过在深层模拟口袋中消费的周期性问题，并为其环境的变化生产热休克蛋白，从而使其能够自我防御系统成为可能。

Porphyromonas gingivalis (P.g.) predominantly consumes arginine in the anaerobic BHI-broth, suggesting that this amino acid could be the primary energy source. Arginine carboxypeptidase, which is one of enzymes to participate in releasing arginine from peptides, was isolated and purified from cytoplasm of P.g. cells. SDS-PAGE of the enzyme with 2-mercaptoethanol revealed the presence of three major bands of 42, 33 and 32kDa, of which 30 amino acid sequences at NHィイD22ィエD2-terminal were identical, YEWNAYPTYEAYISMMEEFQT-KYPSLXTXS. The open reading frame (ORF), suspected from the nucleotide sequences corresponding to the N-terminal amino acids on the data bases containing unfinished P.g. W83 genome, showed to include zinc-binding regions signature, suggesting a zinc carboxypeptidase. In order to release arginine from the inside of the peptides, this enzyme, which was determined as a exo-type of carboxypeptidase, could work in combination with the trypsin like enzyme (cystein protease), which is considered as the main periodontopathogen of this bacterium. In relation to the arginine consumption and energy production, cell extracts of P. g. clearly demonstrated enzyme activities for the arginine deminase pathway and the adenosine triphosphate production. Besides arginine catabolism, P. g. conserved the heat-shock protein and increased the synthesis after a thermal shock, suggesting the physiologic role to protect their own cells. These results show that P. g. possesses self-defense systems by consuming periodontal tissues in the deep anaerobic pockets and producing heat-shock proteins for the changes of their environments.