Mergenhagen S E, Sandberg A L, Chassy B M, Brennan M J, Yeung M K, Donkersloot J A, Cisar J O
Laboratory of Microbiology and Immunology, National Institute of Dental Research, Bethesda, Maryland 20892.
Rev Infect Dis. 1987 Sep-Oct;9 Suppl 5:S467-74. doi: 10.1093/clinids/9.supplement_5.s467.
The two varieties of fimbriae identified on oral strains of actinomyces have distinct functional properties. The type 1 fimbriae of Actinomyces viscosus T14V mediate attachment to saliva-treated hydroxyapatite. Type 2 fimbriae--on A. viscosus and the only fimbriae detected on A. naeslundii WVU45--are associated with lectin activity. Interaction of these fimbriae with complementary receptors initiates bacterial attachment to Streptococcus sanguis 34 and sialidase-treated epithelial cells and the killing of actinomyces by polymorphonuclear leukocytes (PMNs). Galactose, N-acetylgalactosamine (GalNAc), and related oligosaccharides inhibit these processes, and mutants lacking type 2 fimbriae do not participate in them. The actinomyces lectin is similar to lectins from Ricinus communis and Bauhinia purpurea that agglutinate certain strains of oral streptococci, block attachment of actinomyces to epithelial cells, and inhibit killing of actinomyces by PMNs. The S. sanguis receptor for the actinomyces lectin comprises repeating hexasaccharide units with GalNAc termini. Used as probes, the peanut agglutinin, with specificity for Gal(beta-3)GalNAc, and the lectin from B. purpurea detect a 160-kilodalton (kdal) band in SDS-PAGE-separated epithelial cell extracts and a 100-kdal band in PMN extracts. These may be receptors for type 2 fimbriae. A. viscosus genes encoding subunits of types 1 and 2 fimbriae have been cloned in Escherichia coli; the type 1 subunit is 65 kdal and the type 2 subunit is 59 kdal. Submandibular immunization of mice with a mixture of type 1 and type 2 fimbriae evokes the production of IgA and IgG antibodies in serum and saliva that inhibit in vitro adsorption of A. viscosus to SHA. These antibodies may modulate colonization of teeth by this organism.
在放线菌口腔菌株中鉴定出的两种菌毛具有不同的功能特性。粘性放线菌T14V的1型菌毛介导与经唾液处理的羟基磷灰石的附着。2型菌毛——存在于粘性放线菌以及在内氏放线菌WVU45中检测到的唯一菌毛——与凝集素活性相关。这些菌毛与互补受体的相互作用引发细菌对血链球菌34和经唾液酸酶处理的上皮细胞的附着，以及多形核白细胞（PMN）对放线菌的杀伤。半乳糖、N - 乙酰半乳糖胺（GalNAc）及相关寡糖可抑制这些过程，缺乏2型菌毛的突变体不参与其中。放线菌凝集素类似于蓖麻和紫羊蹄甲的凝集素，可凝集某些口腔链球菌菌株、阻止放线菌附着于上皮细胞并抑制PMN对放线菌的杀伤。放线菌凝集素的血链球菌受体由带有GalNAc末端的重复六糖单元组成。具有对Gal(β - 3)GalNAc特异性的花生凝集素以及紫羊蹄甲的凝集素用作探针时，可在SDS - PAGE分离的上皮细胞提取物中检测到一条160千道尔顿（kdal）的条带，在PMN提取物中检测到一条100 kdal的条带。这些可能是2型菌毛的受体。编码1型和2型菌毛亚基的粘性放线菌基因已在大肠杆菌中克隆；1型亚基为65 kdal，2型亚基为59 kdal。用1型和2型菌毛的混合物对小鼠进行下颌下免疫可在血清和唾液中诱生IgA和IgG抗体，这些抗体可在体外抑制粘性放线菌对唾液处理的羟基磷灰石（SHA）的吸附。这些抗体可能调节该生物体在牙齿上的定植。
