アブストラクト（33巻4号：神奈川歯学）

神奈川歯学

Japanese

Title　： Porphyromonas gingivalisにおける線毛遺伝子(fimA381)による形質転換に伴う性状の変化
Subtitle　： 原著
Authors　： 加藤大輔, 高橋祐介, 吉本尚, 梅本俊夫
Authors（kana）　：
Organization　： 神奈川歯科大学口腔細菌学教室
Journal　： 神奈川歯学
Volume　： 33
Number　： 4
Page　： 149-162
Year/Month　： 1998 / 12
Article　： 原著
Publisher　： 神奈川歯科大学学会
Abstract　： 「緒言」 成人性歯周炎の原因菌と考えられているPorphyromonas gingivalis (P. gingivalis)の病原因子として, コラゲナーゼ, トリプシン様プロテアーゼ, およびリポ多糖(LPS)に加えて, 菌体表層に存在する線毛が挙げられている. 線毛の機能については, 細胞やハイドロキシアパタイトへの付着, 他菌種との共凝集といった細胞間作用に大きく関っていることを示唆する報告が多いことから, 菌体の歯周ポケット内への定着, およびそれに伴うプラークの形成に関する因子と考えられ, 同菌の病原性において大きな役割を果たしていると思われる. 従って, 同菌の線毛の機能を解明することは, 歯周病の病因を明らかにするうえで極めて重要であり, その目的のためには, 分子遺伝学的手法も有用な手段の一つとなり得ると考えられる. P. gingivalis線毛の分離と精製に初めて成功したYoshimuraらは, P. gingivalis 381株線毛の主要構成成分が, 分子量43-kDaのタンパク質(フィンブリリン)であることを明らかにしたことから, 線毛の基本構造は, フィンブリリンが重合することにより形成されるものと推定されるに至った.
Practice　： 歯科学
Keywords　： Porphyromonas gingivalis, 線毛遺伝子, 形質転換

English

Title　： Alteration of Biological Properties in Porphyromonas gingivalis Transformed with a Fimbrillin Gene, fimA381
Subtitle　：
Authors　： Daisuke KATO, Yusuke TAKAHASHI, Hisashi YOSHIMOTO, Toshio Umemoto
Authors（kana）　：
Organization　： Department of Oral Microbiology, Kanagawa Dental College
Journal　： Kanagawa Shigaku
Volume　： 33
Number　： 4
Page　： 149-162
Year/Month　： 1998 / 12
Article　： Original article
Publisher　： Kanagawa Odontological Society
Abstract　： [Abstract] Transformation of Porphyromonas gingivalis with foreign genes is difficult due to the presence of a restriction-modification system. In this study, a recombinant plasmid pYHF 1, containing a gene fimA381 encoding the main subunit of the fimbriae of P. gingivalis 381 was constructed by ligating a linear pUC 13 Bg 12.1 fragment into pYH 420, and was successfully electroporated into YH 522, a restriction-deficient P. gingivalis host strain constructed in our previous study. Several wild, restriction-positive P. gingivalis strains, including O-131, W 50, BLO-1, BH 18/10 and ATCC 33277, also accepted pYHF 1 when the plasmid DNA purified from P. gingivalis YH 522 was used as the donor, albeit at an extremely low frequency. Among these host strains, O-131, W 50 and BLO-1, exhibited a difference in the fimbrial antigenicity from strain 381 as well as YH 522, although the other 2 strains, BH 18/10 and ATCC 33277, exhibited the same antigenicity as 381. Production of a specific protein with a molecular weight of 41-kDa was observed by SDS-PAGE in all fimA transformants irrespective of the host strain. This product was considered to be the recombinant fimbrillin, because it reacted with a polyclonal antiserum raised against the fimbriae of ATCC 33277, a type strain of P. gingivalis containing the same fimbrial antigenicity as 381. In addition, all transformants except strain ATCC 33277 exhibited characteristic fimbrial structures (recombinant fimbriae), which were distinguishable by electron microscopy from their native fimbriae, although a marked difference was observed in the amount of gene expression as shown by the density of the protein bands. Moreover, an apparent relationship between the amounts of the recombinant fimbrillin and the recombinant fimbriae was also observed. We then compared various biological properties such as cell-surface hydrophobicity, ability of attachment to the epithelial cells, co-aggregation with other bacteria, and hemagglutination activity between the transformants containing the recombinant fimbriae and the host cells without fimbriae. In all cases where increased expression of the recombinant fimbriae was clearly observed, the transformants exhibited reduced attachment ability, co-aggregation and hydrophobicity. No difference in hemagglutination activity, however, was observed between any combination of the fimA-containing and non-containing cells. These results suggested that the recombinant fimbriae produced by the fimA gene have some unknown difference in their biological natures from the native fimbriae, possibly due to the lack of some minor components which are essential for co-aggregation with other bacteria and attachment to epithelial cells.
Practice　： Dentistry
Keywords　： Porphyromonas gingivalis