title: Rv3134c/devR/devS operon of Mycobacterium bovis BCG is differentially transcribed under "in vitro" stress conditions.
abstract: DevR is a transcriptional regulator that mediates the genetic response of Mycobacterium tuberculosis and Mycobacterium bovis to oxygen limitation and nitric oxide exposure. devR is part of an operon that includes the genes devS and Rv3134c, which encode an oxygen sensor protein and a protein that contains a universal stress protein domain, respectively. Here, we report the transcriptional analysis and quantitative expression of Rv3134c/devR/devS under in vitro stress conditions including oxygen limitation, low nutrients and ex vivo macrophage infection. At least three different promoters were found to control Rv3134c/devR/devS expression under the stresses tested. Two promoters were identified upstream of devR, one was active under hypoxia and the other under nutrient starvation. A single promoter was identified upstream of Rv3134c, and transcripts from this promoter were detected only under hypoxia. Rv3134c to devR were found to be co-transcribed only under hypoxia, whereas devR/devS were co-transcribed both in aerobiosis and starvation. RT-qPCR showed an increase in the ratio hypoxia/aerobiosis and in starvation/nutrients in all genes. devR/devS showed transient expression in the first days of macrophage infection. Our results indicate that Rv3134c/devR/devS of M. bovis BCG constitutes an operon with complex regulation that participates in bacterial response against a wide range of stresses.
authors.affiliation: Corporación Corpogen, Carrera 5 No. 66A-34, Bogotá, Colombia.
authors.forename: Juan Germán
authors.initials: JG
authors.lastname: Rodriguez
authors.forename: Claudia Sofía
authors.initials: CS
authors.lastname: Burbano
authors.forename: Carmen
authors.initials: C
authors.lastname: Nuñez
authors.forename: Clara Eugenia
authors.initials: CE
authors.lastname: González
authors.forename: María Mercedes
authors.initials: MM
authors.lastname: Zambrano
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: García
authors.forename: Patricia
authors.initials: P
authors.lastname: Del Portillo
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D009163:Mycobacterium bovis / Q000235:genetics* / Q000378:metabolism; D009569:Nitric Oxide; D009876:Operon / Q000235:genetics*; D010100:Oxygen; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D006656:Protamine Kinase / Q000235:genetics* / Q000378:metabolism; D013312:Stress, Physiological / Q000502:physiology*; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D009569:Nitric Oxide; C506260:DevS protein, Mycobacterium tuberculosis; D006656:Protamine Kinase; D010100:Oxygen