Dusek D M, Progulske-Fox A, Whitlock J, Brown T A
Department of Oral Biology, University of Florida, Gainesville 32610.
Infect Immun. 1993 Mar;61(3):940-6. doi: 10.1128/iai.61.3.940-946.1993.
Identification of surface macromolecules of Porphyromonas gingivalis that act as virulence factors in periodontal disease has important implications for studying host-parasite interactions as well as for potential vaccine development. The objective of this study was to determine whether a cloned, P. gingivalis hemagglutinin gene could be expressed in an intact form in an avirulent Salmonella typhimurium vaccine construct and to characterize the recombinant protein. The recombinant protein was purified from the vaccine strain, characterized, and tested for biological activity as a competitive inhibitor of hemagglutination. Cells of S. typhimurium SL3261/pST7 grown in Luria broth were broken by sonic disruption and fractionated. The purified recombinant protein was found to inhibit hemagglutination of erythrocytes by whole P. gingivalis cells. The same purified protein was analyzed for its N-terminal amino acid sequence and amino acid composition and found to match that predicted from the nucleotide sequence of the cloned gene. These results indicate that a surface macromolecule of P. gingivalis can be expressed in an intact and biologically active form in a Salmonella carrier strain.
鉴定牙龈卟啉单胞菌中作为牙周病致病因子的表面大分子，对于研究宿主与寄生虫的相互作用以及潜在疫苗的开发具有重要意义。本研究的目的是确定克隆的牙龈卟啉单胞菌血凝素基因能否在无毒力的鼠伤寒沙门氏菌疫苗构建体中完整表达，并对重组蛋白进行表征。从疫苗菌株中纯化重组蛋白，对其进行表征，并作为血凝抑制竞争剂测试其生物活性。在Luria肉汤中生长的鼠伤寒沙门氏菌SL3261/pST7细胞经超声破碎和分级分离。发现纯化的重组蛋白可抑制牙龈卟啉单胞菌全细胞对红细胞的血凝作用。对同一纯化蛋白的N端氨基酸序列和氨基酸组成进行分析，发现与克隆基因的核苷酸序列预测结果相符。这些结果表明，牙龈卟啉单胞菌的一种表面大分子能够在沙门氏菌载体菌株中完整且具有生物活性地表达。
