Lépine G, Progulske-Fox A
Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, USA.
Oral Microbiol Immunol. 1996 Apr;11(2):65-78. doi: 10.1111/j.1399-302x.1996.tb00339.x.
A third hemagglutinin gene, defined as hagC, was cloned from Porphyromonas gingivalis 381 and sequenced. This gene was found to encode a protein highly homologous (98.6%) to the previously reported HagB hemagglutinin protein. The upstream and downstream regions of hagB and hagC were found to share less than 40% homology compared with 99% for their open reading frames. The antigenic relationship between the two hemagglutinins was demonstrated by Western blot analysis. When expressed in an in vitro transcription-translation system, both genes encoded a protein with a molecular mass of 49 kDa. As determined by reverse transcription polymerase chain reaction, the steady-state levels of hagB and hagC mRNAs were found to vary according to the growth phase and hemin concentration. The amount of transcripts decreased in hemin-limited conditions or in the absence of hemin. Furthermore, hagB mRNAs were detected in the early logarithmic growth phase compared with the hagC transcripts, which were detected only in the mid-exponential phase of growth.
从牙龈卟啉单胞菌381中克隆出第三个血凝素基因，定义为hagC，并进行了测序。发现该基因编码一种与先前报道的HagB血凝素蛋白高度同源（98.6%）的蛋白质。发现hagB和hagC的上游和下游区域的同源性低于40%，而它们的开放阅读框的同源性为99%。通过蛋白质免疫印迹分析证实了两种血凝素之间的抗原关系。当在体外转录-翻译系统中表达时，这两个基因都编码一种分子量为49 kDa的蛋白质。通过逆转录聚合酶链反应确定，发现hagB和hagC mRNA的稳态水平根据生长阶段和血红素浓度而变化。在血红素限制条件下或无血红素时，转录本数量减少。此外，与仅在生长指数中期检测到的hagC转录本相比，在对数生长早期检测到了hagB mRNA。
