title: Borrelia burgdorferi oxidative stress regulator BosR directly represses lipoproteins primarily expressed in the tick during mammalian infection.
abstract: Differential gene expression is a key strategy adopted by the Lyme disease spirochaete, Borrelia burgdorferi, for adaptation and survival in the mammalian host and the tick vector. Many B. burgdorferi surface lipoproteins fall into two distinct groups according to their expression patterns: one group primarily expressed in the tick and the other group primarily expressed in the mammal. Here, we show that the Fur homologue in this bacterium, also known as Borrelia oxidative stress regulator (BosR), is required for repression of outer surface protein A (OspA) and OspD in the mammal. Furthermore, BosR binds directly to sequences upstream of the ospAB operon and the ospD gene through recognition of palindromic motifs similar to those recognized by other Fur homologues but with a 1 bp variation in the spacer length. Putative BosR binding sites have been identified upstream of 156 B. burgdorferi genes. Some of these genes share the same expression pattern as ospA and ospD. Most notably, 12 (67%) of the 18 genes previously identified in a genome-wide microarray study to be most significantly repressed in the mammal are among the putative BosR regulon. These data indicate that BosR may directly repress transcription of many genes that are downregulated in the mammal.
authors.affiliation: Department of Veterinary Biosciences, The Ohio State University, 1900 Coffey Road, Columbus, OH, 43210, USA.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Poonam
authors.initials: P
authors.lastname: Dadhwal
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Cheng
authors.forename: Michael R
authors.initials: MR
authors.lastname: Zianni
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Rikihisa
authors.forename: Fang Ting
authors.initials: FT
authors.lastname: Liang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000096:biosynthesis*; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis*; D001428:Bacterial Vaccines / Q000096:biosynthesis*; D025065:Borrelia burgdorferi / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D008074:Lipoproteins / Q000096:biosynthesis*; D018384:Oxidative Stress; D051381:Rats; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000954:Antigens, Surface; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D008074:Lipoproteins; C072045:OspA protein; D012097:Repressor Proteins; C077524:outer surface protein D, Borrelia burgdorferi