MICROBIAL EVOLUTION--PATTERN OF GENETIC/PHENOTYPIC VARIATION IN CATOPHILIC YEAST

酵母菌既是重要的病原菌，又是自然界中的非致病性微生物， 社区.有效控制致病性酵母菌依赖于我们的 自然界作为病原体来源的知识， 病原微生物种群内遗传变异的来源。一个 妨碍对病原体/自然种群的理解 相互作用是我们所知道的致病性 酵母和酵母的自然种群。这笔赠款将增加 我们对自然酵母菌群进化史的了解 它既是天然酵母群落的模型，又含有 几种酵母菌是人类的病原体 为了实现这一点，我将使用遗传变异（在整个 RAPD（随机扩增多态性DNA）或AFLP （匿名片段长度多态性）变异或两者）来构建 相关和不相关嗜恶菌菌株的致病性。的 遗传学将与生理特征的模式相关联， 菌株的地理来源、宿主植物类型和杀伤/敏感性 表型，以追踪社区的进化历史。我 将能够确定社区是否作为一个单位进化， 代表了几个独立的群落， 在不同的时间和地点栖息。另外，我会评估 错误的来源是特定于基因数据的种类， 收集的能力标准分支技术，准确地 揭示菌株之间的真实系统发育关系。我既这样行 通过旨在评估数据误差水平的实验， 各种误差水平和误差来源对 找到真正进化树的可能性 参与该项目的学生将学习如何识别酵母菌; 遗传和系统发育分析;并组织，分析，并提出 他们的数据.该项目的跨学科方面将整合 概念在不同的课程，并将扩大学生的 生物学的观点，因此，鼓励他们扩大他们的 选择生物学职业时的观点。

Yeasts are both important pathogens and members of natural, non-pathogenic communities. Effective control of pathogenic yeasts is dependent on our knowledge of the natural communities as a source of the pathogen and as a source of genetic variation within pathogenic microbial populations. An impediment to the understanding of pathogen/natural population interactions is the large gap between what is known about pathogenic yeasts and about natural populations of yeast. This grant will increase our knowledge of the evolutionary history of a natural yeast community which both serves a model for natural yeast communities and contains several species of yeast that are human pathogens. To accomplish this, I will use genetic variation (measured across the genome either as RAPD (randomly amplified polymorphic DNA) or AFLP (anonymous fragment length polymorphic) variation or both) to construct phylogenies of both related and unrelated cactophilic strains. The phylogenies will be correlated with patterns in physiological profile, geographic origins of the strains, host plant type, and killer/sensitive phenotype in order to trace the evolutionary history of the community. I will be able to determine if the community has evolved as a unit or represents several separate communities assembled within the cactophilic habitat at different times and places. In addition, I will assess effect of sources of error that are specific to the kinds of genetic data being collected on the ability of standard cladistic techniques to accurately uncover the true phylogenetic relationships among strains. I will do this through experiments designed to assess the level of error in the data and a simulation model of the effect of various levels and sources of error on the likelihood of finding the true cladogram. Students involved in the project will learn to identify yeasts; to do genetic and phylogenetic analyses; and to organize, analyze, and present their data. The interdisciplinary aspects of the project will integrate concepts presented in different courses and will widen the students' perspectives in biology and, consequently, encourage them to widen their perspectives when choosing a career in biology.