Members of the RidA (YjgF/YER057c/UK114) protein family are broadly conserved across the domains of life. In vitro, these proteins deaminate 3- or 4-carbon enamines that are generated as mechanistic intermediates of pyridoxal 5'-phosphate (PLP)-dependent serine/threonine dehydratases. The three-carbon enamine 2-aminoacrylate can inactivate some enzymes by forming a covalent adduct via a mechanism that has been well characterized in vitro. The biochemical activity of RidA suggested that the phenotypes of ridA mutant strains were caused by the accumulation of reactive enamine metabolites. The data herein show that in ridA mutant strains of Salmonella enterica, a stable 2-aminoacrylate (2-AA)/PLP adduct forms on the biosynthetic alanine racemase, Alr, indicating the presence of 2-aminoacrylate in vivo. This study confirms the deleterious effect of 2-aminoacrylate generated by metabolic enzymes and emphasizes the need for RidA to quench this reactive metabolite.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3754577PMC
http://dx.doi.org/10.1128/JB.00463-13DOI Listing

Publication Analysis

Top Keywords

pyridoxal 5'-phosphate
8
rida mutant
8
mutant strains
8
2-aminoacrylate
5
rida
5
absence rida
4
rida endogenous
4
endogenous 2-aminoacrylate
4
2-aminoacrylate inactivates
4
inactivates alanine
4

Similar Publications

This work presents the development of an amperometric biosensor for detecting aspartate aminotransferase (AST) activity in biological fluids using a platinum disk electrode as the working transducer. Optimal concentrations of substrates (aspartate, α-ketoglutarate) and the coenzyme (pyridoxal phosphate) were determined to ensure efficient biosensor operation. A semi-permeable poly-m-phenylenediamine membrane was applied to enhance selectivity against electroactive interferents.

View Article and Find Full Text PDF

Mutations in the SLC25A38 gene are responsible for the second most common form of congenital sideroblastic anemia (CSA), a severe condition for which no effective treatment exists. We developed and characterized a K562 erythroleukemia cell line with markedly reduced expression of the SLC25A38 protein (A38-low cells). This model successfully recapitulated the main features of CSA, including reduced heme content and mitochondrial respiration, increase in mitochondrial iron, ROS levels and sensitivity to oxidative stress.

View Article and Find Full Text PDF

The first monomeric pyridoxal-5'-phosphate (PLP)-dependent transaminase from a marine, aromatic-compound-degrading, sulfate-reducing bacterium Tol2, has been studied using structural, kinetic, and spectral methods. The monomeric organization of the transaminase was confirmed by both gel filtration and crystallography. The PLP-dependent transaminase is of the fold type IV and deaminates D-alanine and ()-phenylethylamine in half-reactions.

View Article and Find Full Text PDF

Pyridoxal-5-phosphate (PLP) enhances the synthesis of endogenous hydrogen sulfide, a potent regulator of cell metabolism. We used 24-month-old rats to investigate the PLP mitoprotective function in the aging heart. We demonstrated improvement of mitochondrial bioenergetic functions, inhibition of mPTP opening after PLP administration.

View Article and Find Full Text PDF

Bacterial methionine biosynthesis is an attractive target for research due to its central role in cellular metabolism, as most steps of this pathway are missing in mammals. Up to now little is known about sulfur metabolism in pathogenic Clostridia species, making the study of the enzymes of Cys/Met metabolism in Clostridium tetani particularly relevant. Analysis of the C.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!