The genome-scale DNA-binding profile of BarR. The genome-scale DNA-binding profile of BarR

The Leucine-responsive Regulatory Protein (Lrp) family is a widespread family of regulatory transcription factors in prokaryotes. BarR is an Lrp-like transcription factor in the model archaeon Sulfolobus acidocaldarius that activates the expression of a β-alanine aminotransferase gene, which is involved in β-alanine degradation. In contrast to classical Lrp-like transcription factors, BarR is not responsive to any of the α-amino acids but interacts specifically with β-alanine. Besides the juxtaposed β-alanine aminotransferase gene, other regulatory targets of BarR have not yet been identified although β-alanine is the precursor of coenzyme A and thus an important central metabolite. The aim of this study is to extend the knowledge of the DNA-binding characteristics of BarR and of its corresponding regulon from a local to a genome-wide perspective.

亮氨酸响应调控蛋白（Leucine-responsive Regulatory Protein，Lrp）家族是原核生物中广泛分布的一类调控型转录因子。BarR是模式古菌嗜酸硫化叶菌（Sulfolobus acidocaldarius）中的一种类Lrp转录因子，可激活参与β-丙氨酸降解的β-丙氨酸转氨酶（β-alanine aminotransferase）基因的表达。与经典类Lrp转录因子不同，BarR不会对任何α-氨基酸（α-amino acids）产生应答，而是仅与β-丙氨酸特异性结合。尽管β-丙氨酸作为辅酶A（coenzyme A）的前体，属于重要的中心代谢物，但除该毗邻的β-丙氨酸转氨酶基因外，目前尚未鉴定出BarR的其他调控靶点。本研究旨在从全基因组视角，拓展对BarR DNA结合特性及其对应调控子（regulon）的认知，将研究范畴从局部延伸至全基因组范围。