Streptococcus-Candida Communication in Oral Biofilms

描述（由申请人提供）：牙菌斑生物膜是在口腔表面发现的多微生物群落，嵌入宿主唾液成分和微生物胞外产物的基质中。这些生物膜为口腔硬组织和软组织疾病提供了感染源。微生物之间的交流反应调节生物膜的结构、组成和致病潜力。口腔链球菌在这方面尤其重要，因为它们是口腔表面的主要定植者。它们的沉积提供了一个附着基质，供潜在致病性生物体（如真菌白色念珠菌）定植，这是人类大多数酵母感染的原因。口腔链球菌与C.建议使用白色念珠菌，以促进口腔携带和持久性的C。白色念珠菌，导致疾病状况，如假牙引起的口腔炎。研究表明，戈登链球菌和C。白色念珠菌涉及互补的和协同的粘附素受体分子。链球菌细胞表面相关抗原I/II家族粘附素，命名为SspA和SspB，靶向酵母细胞表面受体，导致配偶体细胞类型上的其他表面分子的紧密接合。这些粘附过程驱动在形态学、生理学和病理学上独特的混合物种生物膜的发展和积累。本申请的目的是：确定C。白念珠菌SspB蛋白受体。gordonii;确定抗原l/ll家族蛋白识别酵母受体的分子基础，研究基质组成、环境因素和链球菌粘附素表达对链球菌生长发育的影响。戈登氏C.白念珠菌混合生物膜;确定S. gordonii和C.白色念珠菌在生物膜和诱导细胞-细胞接触。这些实验将提供详细的分子信息的主要成分介导的相互作用的S。gordonii和C.白念珠菌和更好地理解的信号和途径，共粘附导致生物膜成熟。这些信息将有助于开发更有效的生物学策略，用于控制多微生物生物膜和治疗性预防C。白色念珠菌过度生长。念珠菌感染是对公共卫生的严重威胁。这项研究设计了控制或预防口腔念珠菌生长的新方法。

DESCRIPTION (provided by applicant): Dental plaque biofilms are polymicrobial communities found on oral surfaces embedded in a matrix of host salivary components and microbial extracellular products. These biofilms provide an infection source for diseases of the oral hard and soft tissues. Communication reactions between the micro-organisms modulate the structure, composition and pathogenic potential of the biofilms. The oral streptococci are especially important in this respect because they are primary colonizers of oral cavity surfaces. Their deposition provides an attachment substrate for colonization by potentially pathogenic organisms such as the fungus Candida albicans, which is the cause of most yeast infections in humans. Co-adhesion between oral streptococci and C. albicans is proposed to facilitate oral carriage and persistence of C. albicans, leading to disease conditions such as denture-induced stomatitis. Studies have demonstrated that inter-microbial binding of Streptococcus gordonii and C. albicans involves complementary and co-operative adhesin- receptor molecules. Streptococcal cell surface-associated antigen I/II family adhesins, designated SspA and SspB, target yeast cell surface receptors, resulting in close engagement of other surface molecules on the partner cell types. These adhesion processes drive the development and accumulation of mixed species biofilms that are morphologically, physiologically and pathogenically unique. The objectives of this application are to: identify the C. albicans receptor for the SspB protein of S. gordonii; define the molecular basis of yeast receptor recognition by antigen l/ll family proteins; investigate the effects of substratum composition, environmental factors and the role of Streptococcal adhesin expression on the development of S. gordonii-C. albicans mixed biofilms; determine patterns of differential gene expression in S. gordonii and C. albicans in biofilms and induced by cell-cell contact. These experiments will provide detailed molecular information on the major components mediating interactions of S. gordonii and C. albicans and better understanding of the signals and pathways by which co-adhesion leads to biofilm maturation. Such information will assist in the development of more effective biologically based strategies for control of polymicrobial biofilms, and for therapeutic prevention of C. albicans overgrowth. Candida yeast infections are a serious threat to public health. This research devises new methods for controlling or preventing growth of Candida in the mouth.