Smith D J, King W F, Wu C D, Shen B I, Taubman M A
Department of Immunology, Forsyth Dental Center, Boston, Massachusetts 02115, USA.
Infect Immun. 1998 Nov;66(11):5565-9. doi: 10.1128/IAI.66.11.5565-5569.1998.
Three purified glucan binding proteins (GBP-2, GBP-3, and GBP-5) from Streptococcus sobrinus 6715 were compared structurally by mass spectroscopy of tryptic fragments and antigenically by Western blot analysis with rat antisera to each GBP or to peptides containing putative glucan binding epitopes of mutans streptococcal glucosyltransferases. Structural and antigenic analyses indicated that GBP-3 and GBP-5 are very similar but that both are essentially unrelated to GBP-2. None of these S. sobrinus GBPs appeared to have a strong antigenic relationship with GBPs from Streptococcus mutans. Thus, S. sobrinus GBP-2 and GBP-3 appear to be distinct proteins with potentially different functions. S. sobrinus GBP-5 may be a proteolytic fragment of GBP-3, or, alternatively, the genes coding for these proteins may be closely related.
对来自远缘链球菌6715的三种纯化的葡聚糖结合蛋白（GBP-2、GBP-3和GBP-5）进行了结构比较，采用胰蛋白酶片段质谱分析法，并通过蛋白质印迹分析进行抗原性比较，使用大鼠抗血清分别针对每种GBP或含有变形链球菌葡糖基转移酶推定葡聚糖结合表位的肽段。结构和抗原性分析表明，GBP-3和GBP-5非常相似，但两者与GBP-2基本无关。这些远缘链球菌GBP中没有一种与变形链球菌的GBP表现出强烈的抗原关系。因此，远缘链球菌GBP-2和GBP-3似乎是具有潜在不同功能的不同蛋白质。远缘链球菌GBP-5可能是GBP-3的蛋白水解片段，或者，编码这些蛋白质的基因可能密切相关。
