RUI: Molecular Phylogenetic Analysis and Biogeography of Spiroplasmas

螺原体可能是地球上数量最多的微生物群之一，因为它们与各种各样的昆虫有关。传统的菌株分类根据血清学将螺原体属分为34个类群，最近对来自北美和欧洲的36株螺原体的分子分析表明，分子系统发育与血清学类群之间存在很强的相关性。目前的项目将在这一初步研究的基础上进行扩展，以包括更多地理上不同的螺原体分离物。结果将解决有关地理多样性，螺旋体-宿主特异性，以及血清学分类和分子系统发育之间的相关性的问题。具体地说，该研究将检查从虻蝇分离的新型螺旋体的地理和血清学不同样本集的分子系统发育关系。之所以选择tabania相关的螺旋体，是因为它们是迄今为止基于血清学研究最彻底的群体。本研究分离的螺原体来自北美、中美洲、南美洲和澳大利亚的虻；并被分为24个独立的血清组。每个血清组的分离株将进行分子分析，并确定分子系统发育关系。本研究的结果将使螺旋体领域进一步依赖DNA序列数据进行菌株分类，并有助于弥合传统血清学和分子系统发育之间的差距。这对螺旋体领域具有重要意义，因为血清学和系统发育之间的相关性将允许对数百种仅通过血清学分类的菌株进行试探性定位。此外，了解螺旋体的生物多样性和生物地理学在农业生产中具有重要的实际应用价值，因为致病物种是柑橘顽固病、玉米侏儒病和蜜蜂死亡的原因。确定螺旋体的地理范围和分布模式可能有助于制定疾病管理战略。最后，本研究为本科生、研究生和首席研究员的职业发展提供了许多机会。该项目将广泛影响代表性不足群体的参与，因为超过80%的首席研究员的本科研究学生来自代表性不足的群体。

AbstractLaura RegassaDEB 0451430Spiroplasmas may be one of the most abundant groups of microbes on earth due to their association with a wide variety of insects. Traditional strain classification divided the genus Spiroplasma into 34 groups based on serology, and recent molecular analysis of 36 strains from North America and Europe suggests a strong correlation between the molecular phylogeny and the serological groups. The current project will expand upon this initial study to include more geographically diverse spiroplasma isolates. The results will address questions concerning geographical diversification, spiroplasma-host specificity, and the correlation between serological classification and molecular phylogeny. Specifically, the research will examine the molecular phylogenetic relationships of a geographically and serologically diverse sample set of novel spiroplasma isolates from tabanid flies. Tabanid-associated spiroplasmas were chosen because they are the most thoroughly studied group to date based on serology. The spiroplasma isolates for this study were obtained from tabanid flies in North America, Meso-America, South America and Australia; and were placed into 24 independent serogroups. Isolates from each serogroup will be subjected to molecular analysis and molecular phylogenetic relationships will be determined. Results from this study will move the spiroplasma field forward to greater reliance on DNA sequence data for strain classification and help to bridge the gap between traditional serology and molecular phylogeny. This has important implications for the spiroplasma field, because a correlation between serology and phylogeny would allow for tentative placement of hundreds of strains that have only been classified serologically. In addition, understanding the biodiversity and biogeography of spiroplasmas has important practical applications in agricultural production, as pathogenic species are responsible for citrus stubborn disease, corn stunt disease and honeybee mortality. Assignment of geographical ranges and distribution patterns for spiroplasmas may help with disease management strategies. Finally, this research provides numerous opportunities for the career development of undergraduate students, graduate students (M.S.), and the Principal Investigator. This project will broadly impact participation of underrepresented groups as over 80% of the Principal Investigator's undergraduate research students have been from underrepresented groups.