Antibiotic Resistance Transfer in Oral Anaerobes

描述（由申请人提供）：细菌物种之间的DNA转移被认为在抗生素耐药性的传播中起重要作用。不幸的是，关于自然细菌种群中发生的遗传转移程度的信息很少。斑块生物膜提供了一个很好的机会来研究一个容易接近的多物种群体的遗传转移机制。种间遗传交换可能涉及抗生素抗性基因和其他毒力因子的横向转移，这可能导致牙周感染对治疗产生耐药性。此外，口腔菌群的成员有可能将抗生素耐药性转移到口腔中短暂定植的其他病原体。口腔细菌水平基因转移的基础分子研究是非常必要的。该提案将概述实验，以启动存在于口腔厌氧菌卟啉单胞菌和普氏菌成员中的tetq编码共轭转座子的分子研究。该提案的具体目标是：1)从临床分离物中“捕获”共轭元件，并通过RFLP分析和共轭分析比较其结构和行为；2)提交具有代表性的元件进行DNA测序，并利用所得信息开发基于基因含量和功能行为的这些元件的分类系统。这些研究将为水平转移元素在人类口腔菌群中的分布和功能提供重要的见解。

DESCRIPTION (provided by applicant): The transfer of DNA between bacterial species is assumed to play an important role in the dissemination of antibiotic resistance. Unfortunately, little information is available on the extent of genetic transfer occurring in natural bacterial populations. Plaque biofilms offer an excellent opportunity to study genetic transfer mechanisms in an easily accessed multi-species population. Interspecies genetic exchange can involve the conjugal horizontal transfer of antibiotic resistance genes and other virulence factors, which may contribute to the development of periodontal infections resistant to therapy. Additionally, members of the oral flora have the potential to transfer antibiotic resistance to other pathogens that are transient colonizers of the mouth. There is a significant need for basic molecular studies into horizontal gene transfer in oral bacteria. This proposal will outline experiments to initiate molecular studies of the tetQ-encoding conjugal transposons present in members of the oral anaerobes Porphyromonas and Prevotella. The Specific Aims of this proposal are 1) to "capture" conjugative elements from clinical isolates and compare their structure and behavior through RFLP analysis and conjugation assays, and 2) to submit a representative element for DNA sequencing, and use the resulting information to develop a classification system for these elements, based on gene content and functional behavior. These studies will provide important insights into the distribution and functionality of horizontally transferred elements in the human oral flora.