EVOLUTION OF DNA UPTAKE IN HAEMOPHILUS AND NEISSERIA

描述（改编自申请人的摘要）：该项目的中心是 流感嗜血杆菌的DNA摄取序列（USS）。它包括一种混合物， 建模实验、基因组分析和实验工作。模型将 试图回答这样一个问题： 从其他细菌中获得核苷酸足以证明 细菌DNA转化能力的进化。在一个单独 通过这种方法，将开发一种模型来测试DNA受体是否 具有序列偏差的转化将导致USS的积累 基因组序列。建模还将检查USS的分布 并试图确定它是否是随机的。基因组 将用放线杆菌的基因组序列进行分析， 伴放线菌、淋病奈瑟菌和脑膜炎奈瑟菌 确定是否相同的组织模式的美国海军适用于这些 有机体H.流感。这些分析将区分单个 和USS的重复拷贝及其在ORF内和ORF之间的分布。的 基因组也将被扫描，以确定它们是否包含基因， 在物种间异常同源实验工作将测试 DNA转化的杀伤是否仅限于H.流感病毒Rd株 以确定致命性是否是一种普遍现象。粘液含有 DNA，因此分析将确定DNA是否可以从 是否有粘液以及H.流感病毒通常生活在 是否抑制转化。USS的特异性将由以下人员进行测试： 合成50聚体USS，所述USS在27个位置中的每一个处与所述50聚体USS相差一个bp。 共有序列，并测试它们的摄取和抑制DNA的能力， 摄取。也将通过以下方法获得序列不同的较大DNA片段： PCR扩增和测试。一艘USS对DNA摄取的绝对必要性 将使用比以前使用的更长的孵育时间进行测试。尝试将 鉴定细菌细胞表面上的USS结合蛋白， 细胞内。如果一个蛋白质可以被识别，它将被测序。尝试 还将确定是否在类核武器中保护USS。

DESCRIPTION (Adapted from the Applicant's Abstract): This project centers on DNA uptake sequences (USS) in Haemophilus influenzae. It includes a mixture of modeling experiments, genomic analyses and experimental work. Modeling will attempt to answer the question whether the benefits expected from the acquisition of nucleotides from other bacteria are sufficient to justify the evolution of bacterial competence for DNA transformation. In a separate approach, a model will be developed to test whether a receptor for DNA transformation with a sequence bias will result in the accumulation of USS sequences in the genome. Modeling will also examine the distribution of USS around the genome and attempt to determine whether it is random or not. Genomic analyses will be performed with genome sequences of Actinobacillus actinomycetemcomitans, Neisseria gonorrhoeae and Neisseria meningitidis to determine whether the same patterns of organization of USS apply to these organisms as to H. influenzae. These analyses will distinguish between single and repeated copies of USS and their distribution within and between ORFs. The genomes will also be scanned to determine whether they contain genes that are unusually homologous across species barriers. Experimental work will test whether killing by DNA transformation is restricted to H. influenzae strain Rd in order to determine whether lethality is a common phenomenon. Mucus contains DNA and therefore analyses will determine whether DNA can be taken up from mucus or not and whether the mucus that H. influenzae normally lives in inhibits transformation or not. The specificity of the USS will be tested by synthesizing 50mer USS that differ by one bp at each of 27 positions from the consensus sequence and testing them for uptake and ability to inhibit DNA uptake. Larger DNA fragments that differ in sequence will also be obtained by PCR amplification and tested. The absolute necessity of an USS for DNA uptake will be tested using longer incubation times than formerly used. Attempts will be made to identify a USS-binding protein on the bacterial cell surface and intracellularly. If a protein can be identified, it will be sequenced. Attempts will also be made to determine whether the USS are protected in nucleoids.