New culture-difficult oral bacterial species, Eubacterium saphenum and its periodontitis-pathogenic characteristics.

自专性厌氧菌系统建立以来，人们认识到口腔菌群中培养困难菌占绝大多数。最近成功分离的许多细菌为厌氧、无糖解革兰氏阳性杆状菌，根据目前的标准可归为真细菌属。其中一种是隐隐梭菌，是在成人牙周炎患者的牙周袋中分离到的优势菌，在患者中普遍存在。为了明确细菌的特征，从口腔各部位分离出了几种新的培养困难菌，并与隐球菌的特征进行了比较，发现它们可归为几种新的未报道菌株，应作为新属或新种提出。成人牙周炎患者血清中隐隐梭菌抗体的高滴度提示该细菌与成人牙周炎的免疫学关联。

It has been recognized since system for obligate anaerobic bacteria was established recently that culture-difficult bacteria were overwhelming in oral bacterial florae. Many of them recently isolated successfully were anaerobic, asaccharolytic gram-positive rods which would be classified to Genus Eubacterium according to the present criteria. One of them was E.saphenum which has been isolated as predominant bacteria from periodontal pockets with adult periodontitis and distributed commonly among the patients.In order to clarify the bacterial characteristics, several kinds of new culture-difficult bacteria were isolated from various oral sites to compare their characteristics with that of E.saphenum, and found that they could be grouped as several new unreported strains which should be proposed for the new genera or species. Immunological association of this bacterial species with adult periodontites was suggested by high titers of serum antibody against E.saphenum in the patients with adult periodontitis.