Regulation of Aromatic Compound Degradation in Acinetobacter

这些研究主要集中在土壤细菌不动杆菌降解芳香族化合物方面。菌株ADP1。分解代谢途径是理解生物学许多方面的模型系统，可以被操纵用于生物修复和产生有用的化学物质。这类项目的成功取决于对微生物代谢和基因调控的透彻了解。该项目的第一个目标是确定最近发现的一种新型转录激活的分子基础。BENM是一种参与菌株ADP1降解苯甲酸的转录调节因子，被发现对两种不同的代谢物有协同反应。多种诱导剂对转录调控的协同调控可以显著改变基因的表达，这可能是一种常见的生物调控特征。这些研究将确定特定的核苷酸和氨基酸序列，这些序列控制BenM如何与不同的效应物和DNA区域相互作用，以调节参与芳香化合物分解代谢的多个基因和操纵子的表达。第二个目标是研究当多种生长底物可用时不动杆菌对碳源的优先消耗。许多土壤细菌以连续的方式降解芳香化合物混合物的成分。然而，芳香族化合物降解菌控制碳源优先消耗的方法尚不清楚。在ADP1中，调节可能发生在转录水平、转录后水平和/或底物摄取到细胞的水平。这项研究项目将解决CATM和BenM如何抑制4-羟基苯甲酸分解代谢所需的基因。

These studies focus on aromatic compound degradation by the soil bacterium Acinetobacter sp. strain ADP1. Catabolic pathways, which serve as model systems for understanding many aspects of biology, can be manipulated for bioremediation and for the generation of useful chemicals. The success of such ventures rests on a thorough understanding of microbial metabolic and genetic regulation. The first objective of this project is to determine the molecular basis for a recently discovered novel type of transcriptional activation. BenM, a transcriptional regulator involved in the degradation of benzoate by strain ADP1, was found to respond synergistically to two different metabolites. The synergistic modulation of transcriptional regulation in response to more than one inducer can significantly alter gene expression and may be a common biological regulatory feature. These studies will determine the specific nucleotide and amino acid sequences that control how BenM interacts with different effectors and DNA regions to regulate the expression of multiple genes and operons involved in aromatic compound catabolism. The second objective is to investigate preferential carbon source consumption by Acinetobacter strains when multiple growth substrates are available. Many soil bacteria degrade the components of a mixture of aromatic compounds in a sequential fashion. However, the method by which aromatic-compound degrading bacteria control the preferential consumption of carbon sources is unclear. In ADP1, regulation may occur at the transcriptional level, the post-transcriptional level, and/or at the level of substrate uptake into the cell. This research project will address how CatM and BenM repress genes needed for 4-hydroxybenzoate catabolism.