Biochemical and structural characterization of a ureidoglycine aminotransferase in the Klebsiella pneumoniae uric acid catabolic pathway.

@article{French2010BiochemicalAS,
  title={Biochemical and structural characterization of a ureidoglycine aminotransferase in the Klebsiella pneumoniae uric acid catabolic pathway.},
  author={Jarrod B. French and Steven E. Ealick},
  journal={Biochemistry},
  year={2010},
  volume={49 29},
  pages={
          5975-7
        }
}
Many plants, fungi, and bacteria catabolize allantoin as a mechanism for nitrogen assimilation. Recent reports have shown that in plants and some bacteria the product of hydrolysis of allantoin by allantoinase is the unstable intermediate ureidoglycine. While this molecule can spontaneously decay, genetic analysis of some bacterial genomes indicates that an aminotransferase may be present in the pathway. Here we present evidence that Klebsiella pneumoniae HpxJ is an aminotransferase that… 
An aminotransferase branch point connects purine catabolism to amino acid recycling.
TLDR
Structural comparison and mutational analysis suggest a molecular rationale for the functional divergence between UGXT and peroxisomal alanine-glyoxylate aminotransferase, a fundamental enzyme for glyoxylates detoxification in humans.
Structural and kinetic insights into the mechanism of 5-hydroxyisourate hydrolase from Klebsiella pneumoniae.
  • J. FrenchS. Ealick
  • Chemistry, Biology
    Acta crystallographica. Section D, Biological crystallography
  • 2011
TLDR
The high-resolution crystal structure of HIUH from the opportunistic pathogen Klebsiella pneumoniae and a mechanism is proposed for the KpHIUH-catalyzed reaction, providing valuable insight into the functional roles of the active-site residues.
Alternative conformation induced by substrate binding for Arabidopsis thalianaN6-methyl-AMP deaminase
TLDR
Structural studies provide the first look of this important metabolic enzyme and shed lights on its catalytic pathway, which holds promise for the structure-based drug design for MAPDA-related diseases.
Ureide metabolism in plant-associated bacteria: purine plant-bacteria interactive scenarios under nitrogen deficiency
TLDR
Given widespread concerns for crop losses due to the drastically changing climate and prevailing agricultural practices, the understanding of the interactive signaling for the purine metabolisms between PAB and plants takes on a major importance, as it may support management decisions necessary to maintain PAB biodiversity and the agricultural services provided by PAB to crops.
Identifying reaction modules in metabolic pathways: bioinformatic deduction and experimental validation of a new putative route in purine catabolism
TLDR
Using the reaction module concept to define at least two successive steps catalyzed by homologous enzymes in pathways alignable by similar chemical reactions will help to trace how the primordial promiscuous enzymes were assembled progressively in functional modules, as the present pathways diverged from ancestral pathways to give birth to the present-day mechanistically diversified superfamilies.
The Multidrug Efflux System AcrABZ-TolC Is Essential for Infection of Salmonella Typhimurium by the Flagellum-Dependent Bacteriophage Chi
TLDR
The importance of a multidrug efflux pump for the infection of Salmonella enterica by a flagellotropic phage is discovered and coadministering antibiotics and flagella-dependent phage may be a particularly potent antibacterial therapy.
Caracterización molecular del metabolismo del alantoato en judía (Phaseolus Vulgaris)
TLDR
Los resultados obtenidos tras bloquear mediante RNAi the expresion of esta proteina sugieren that the AAH es the enzima responsable of la degradacion del alantoato en judia.
Characterization of the gene cluster involved in allantoate catabolism and its transcriptional regulation by the RpiR-type repressor HpxU in Klebsiella pneumoniae.
TLDR
Allantoate released the HpxU repressor from its target operators whereas other purine intermediate metabolites, such as allantoin and oxamate, failed to induce complex dissociation.
Biochemical and structural characterization of Klebsiella pneumoniae oxamate amidohydrolase in the uric acid degradation pathway.
  • K. HicksS. Ealick
  • Biology, Chemistry
    Acta crystallographica. Section D, Structural biology
  • 2016
TLDR
The structure of HpxW is presented and the substrate complex is modeled and a mechanism for catalysis consistent with other members of the Ntn-hydrolase superfamily to be proposed is proposed.
The purinosome, a multi-protein complex involved in the de novo biosynthesis of purines in humans.
TLDR
The most recent discoveries relating to purine biosynthesis are discussed, with particular emphasis upon the dynamic multi-protein complex called the purinosome and the attempts made to exploit this knowledge for drug discovery.
...
...

References

SHOWING 1-10 OF 13 REFERENCES
Ureide catabolism in Arabidopsis thaliana and Escherichia coli.
TLDR
Two enzymes are identified that catalyze the final reactions of purine degradation in the model plant Arabidopsis thaliana and an alternative metabolic route via ureidoglycine transaminase can be predicted for other organisms.
Chemical basis of nitrogen recovery through the ureide pathway: formation and hydrolysis of S-ureidoglycine in plants and bacteria.
TLDR
NMR evidence is reported that the true product of the AAH reaction is S-ureidoglycine, a nonstandard alpha-amino acid that spontaneously releases ammonia in vitro, strengthening the basis for the known sensitivity of the ureide pathway to Mn availability and suggesting a further rationale for the active transport of Mn in the endoplasmic reticulum of plant cells.
Purine Utilization by Klebsiella oxytoca M5al: Genes for Ring-Oxidizing and -Opening Enzymes
TLDR
A 23-gene cluster is identified that encodes the enzymes for utilizing purines as the sole nitrogen source in the enterobacterium Klebsiella oxytoca, and functions for the products of these genes are revealed.
Pyrimidine and purine biosynthesis and degradation in plants.
TLDR
Progress in molecular aspects and recent studies on the regulation and manipulation of nucleotide metabolism in plants are reviewed.
The hpx Genetic System for Hypoxanthine Assimilation as a Nitrogen Source in Klebsiella pneumoniae: Gene Organization and Transcriptional Regulation
TLDR
The proteins involved in the oxidation of hypoxanthine to allantoin or uric acid did not display any similarity to other reported enzymes known to catalyze these reactions but instead are similar to oxygenases acting on aromatic compounds.
Pyridoxal phosphate enzymes: mechanistic, structural, and evolutionary considerations.
TLDR
The combination of new sequences and structures enables better reconstruction of their evolutionary heritage and illuminates unrecognized similarities within this diverse group of enzymes.
Genetic Analysis of a Chromosomal Region Containing Genes Required for Assimilation of Allantoin Nitrogen and Linked Glyoxylate Metabolism in Escherichia coli
TLDR
A systematic analysis of the gene cluster was undertaken to identify genes involved in allantoin utilization, and the products of these genes were overexpressed and shown to have the predicted corresponding enzyme activities.
Completing the uric acid degradation pathway through phylogenetic comparison of whole genomes
TLDR
Through phylogenetic genome comparison, this work identifies here two genes that share with urate oxidase a common history of loss or gain events and shows that the two proteins encoded by mouse genes catalyze two consecutive steps following urate oxidation to 5-hydroxyisourate (HIU): hydrolysis of HIU and decarboxylation of OHCU to give S-allantoin.
Allantoate hydrolysis by allantoate amidohydrolase.
Reaction of aspartate aminotransferase with C5-dicarboxylic acids: comparison with the reaction with C4-dicarboxylic acids.
TLDR
AspAT recognizes the two types of dicarboxylates with different chain lengths by changing the gross conformation of the enzyme protein, which can be explained only when all the protonation states of the Michaelis complex are considered.
...
...