Banas J A, Vickerman M M
Center for Immunology and Microbial Disease, Albany Medical College, NY 12208, USA.
Crit Rev Oral Biol Med. 2003;14(2):89-99. doi: 10.1177/154411130301400203.
The synthesis of extracellular glucan is an integral component of the sucrose-dependent colonization of tooth surfaces by species of the mutans streptococci. In investigators' attempts to understand the mechanisms of plaque biofilm development, several glucan-binding proteins (GBPs) have been discovered. Some of these, the glucosyltransferases, catalyze the synthesis of glucan, whereas others, designated only as glucan-binding proteins, have affinities for different forms of glucan and contribute to aspects of the biology of their host organisms. The functions of these latter glucan-binding proteins include dextran-dependent aggregation, dextranase inhibition, plaque cohesion, and perhaps cell wall synthesis. In some instances, their glucan-binding domains share common features, whereas in others the mechanism for glucan binding remains unknown. Recent studies indicate that at least some of the glucan-binding proteins modulate virulence and some can act as protective immunogens within animal models. Overall, the multiplicity of GBPs and their aforementioned properties are testimonies to their importance. Future studies will greatly advance the understanding of the distribution, function, and regulation of the GBPs and place into perspective the facets of their contributions to the biology of the oral streptococci.
胞外葡聚糖的合成是变形链球菌对牙齿表面进行蔗糖依赖性定植的一个重要组成部分。在研究人员试图了解菌斑生物膜形成机制的过程中，发现了几种葡聚糖结合蛋白（GBP）。其中一些，即葡糖基转移酶，催化葡聚糖的合成，而其他一些，仅被称为葡聚糖结合蛋白，对不同形式的葡聚糖具有亲和力，并对其宿主生物体的生物学特性有所贡献。这些后一类葡聚糖结合蛋白的功能包括葡聚糖依赖性聚集、葡聚糖酶抑制、菌斑黏附，或许还包括细胞壁合成。在某些情况下，它们的葡聚糖结合结构域具有共同特征，而在其他情况下，葡聚糖结合机制仍不清楚。最近的研究表明，至少一些葡聚糖结合蛋白可调节毒力，并且有些在动物模型中可作为保护性免疫原。总体而言，GBP的多样性及其上述特性证明了它们的重要性。未来的研究将极大地推动对GBP的分布、功能和调控的理解，并正确认识它们对口腔链球菌生物学特性贡献的各个方面。
