Schifferle R E, Shostad S A, Bayers-Thering M T, Dyer D W, Neiders M E
Department of Oral Biology and Periodontology, State University of New York at Buffalo 14214-3092, USA.
J Endod. 1996 Jul;22(7):352-5. doi: 10.1016/S0099-2399(96)80216-0.
Porphyromonas gingivalis has been shown to require hemin or hemoglobin for in vitro growth. We have previously shown that protoporphyrin IX and inorganic iron can replace the hemin requirement, suggesting that the hemin requirement of this microorganism is actually a porphyrin requirement. We examined the effect of protoporphyrin IX limitation to P. gingivalis strain A7A1-28 in the presence of sufficient iron on growth characteristics, proteolytic enzyme production, virulence in a mouse abscess model, and expression of membrane proteins. Bacterial cells were grown in medium varying between 0 to 5 microM reduced growth by at least 50%. Protoporphyrin IX availability did not affect proteolytic enzyme production or virulence in a mouse abscess model. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane preparations demonstrated that protoporphyrin IX limitation induced the expression of new proteins at 42, 34, 30, 29, and 18 kDa and suppressed the production of proteins at 47, 27, 17, and 15 kDa. These studies suggest that in vivo protoporphyrin availability may modulate membrane protein expression and in turn affect host immune responses against P. gingivalis.
牙龈卟啉单胞菌已被证明在体外生长需要血红素或血红蛋白。我们之前已经表明，原卟啉IX和无机铁可以替代对血红素的需求，这表明这种微生物对血红素的需求实际上是对卟啉的需求。我们研究了在铁充足的情况下，原卟啉IX限制对牙龈卟啉单胞菌A7A1 - 28菌株生长特性、蛋白水解酶产生、在小鼠脓肿模型中的毒力以及膜蛋白表达的影响。细菌细胞在0至5微摩尔之间变化的培养基中生长，生长减少至少50%。原卟啉IX的可利用性不影响蛋白水解酶的产生或在小鼠脓肿模型中的毒力。膜制剂的十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳表明，原卟啉IX限制诱导了42、34、30、29和18 kDa新蛋白的表达，并抑制了47、27、17和15 kDa蛋白的产生。这些研究表明，体内原卟啉的可利用性可能调节膜蛋白表达，进而影响宿主针对牙龈卟啉单胞菌的免疫反应。
