The metabolism of (R)-3-hydroxybutyrate is regulated by the enhancer-binding protein PA2005 and the alternative sigma factor RpoN in Pseudomonas aeruginosa PAO1
Year: 2015
Type: article
Abstract: A variety of soil-dwelling bacteria produce polyhydroxybutyrate (PHB), which serves as a source of energy and carbon under nutrient deprivation. Bacteria belonging to the genus Pseudomonas do not generally produce PHB but are capable of using the PHB degradation product (R)-3-hydroxybutyrate [(R)-3-HB] as a growth substrate. Essential to this utilization is the NAD+-dependent dehydrogenase BdhA that converts (R)-3-HB into acetoacetate, a molecule that readily enters central metabolism. Apart from the numerous studies that had focused on the biochemical characterization of BdhA, there was nothing known about the assimilation of (R)-3-HB in Pseudomonas, including the genetic regulation of bdhA expression. This study aimed to define the regulatory factors that govern or dictate the expression of the bdhA gene and (R)-3-HB assimilation in Pseudomonas aeruginosa PAO1. Importantly, expression of the bdhA gene was found to be specifically induced by (R)-3-HB in a manner dependent on the alternative sigma factor RpoN and the enhancer-binding protein PA2005.This mode of regulation was essential for the utilization of (R)-3-HB as a sole source of energy and carbon. However, non-induced levels of bdhA expression were sufficient for P. aeruginosa PAO1 to grow on ( ± )-1,3-butanediol, which is catabolized through an (R)-3-HB intermediate. Because this is, we believe, the first report of an enhancer-binding protein that responds to (R)-3-HB, PA2005 was named HbcR for (R)-3-hydroxybutyrate catabolism regulator.
Source: Microbiology
DOI: 10.1099/mic.0.000163
Institution: SUNY College of Environmental Science and Forestry
Language: English
Subfield: Biomaterials
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, Edna Bailey Sussman Foundation, State University of New York, National Institutes of Health, National Institute of General Medical Sciences, National Institute of Diabetes and Digestive and Kidney Diseases, Division of Chemical, Bioengineering, Environmental, and Transport Systems, European Social Fund
Awards: G5760201950, SusChEM: Engineering E. coli for improved production of polyhydroxyalkanoate (PHA)-based biodegradable plastics, Defining the inputs and outputs of enhancer-binding protein regulation in Pseudomonas aeruginosa, G9000098002, G9000268964, Center for Cystic Fibrosis Translational Research in the Post-CFTR modulator Era, G906614111
OpenAlex ID: W1955755371