D-Glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic eubacterium, Thermotoga maritima, is extremely thermostable showing a thermal transition beyond 105 degrees C. At low temperature, 'cold denaturation' becomes detectable only in the presence of destabilizing agents. Reconstitution after preceding denaturation depends on temperature. At 0 degree C, no significant recovery of activity is detectable, whereas between 30 and 100 degrees C reactivation reaches up to 85%. Shifting the temperature from low values to the range of optimum reconstitution releases the trapped intermediate in a fast reaction. Evidence from ultra-centrifugal analysis and far-UV circular dichroism proves the intermediate to be partially assembled to the tetramer, with most of its native secondary structure restored in a fast reaction. Fluorescence emission exhibits at least biphasic kinetics with the rate-limiting step(s) reflecting local adjustments of aromatic residues involved in tertiary contacts in the native state of the enzyme.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/0014-5793(91)81268-d | DOI Listing |
J Neurochem
September 2024
Department of Chemistry, University of Oslo, Norway.
D-Glyceraldehyde, a reactive aldehyde metabolite of fructose and glucose, is neurotoxic in vitro by forming advanced glycation end products (AGEs) with neuronal proteins. In Alzheimer's disease brains, glyceraldehyde-containing AGEs have been detected intracellularly and in extracellular plaques. However, little information exists on how the brain handles D-glyceraldehyde metabolically or if glyceraldehyde crosses the blood-brain barrier from the circulation into the brain.
View Article and Find Full Text PDFBiochemistry
March 2024
Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States.
The bacterial metabolic enzyme 1-deoxy-d-xylulose-5-phosphate synthase (DXPS) catalyzes the thiamin diphosphate (ThDP)-dependent formation of DXP from pyruvate and d-glyceraldehyde-3-phosphate (d-GAP). DXP is an essential bacteria-specific metabolite that feeds into the biosynthesis of isoprenoids, pyridoxal phosphate (PLP), and ThDP. DXPS catalyzes the activation of pyruvate to give the C2α-lactylThDP (LThDP) adduct that is long-lived on DXPS in a closed state in the absence of the cosubstrate.
View Article and Find Full Text PDFBiomolecules
October 2021
State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200438, China.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a highly conserved enzyme involved in the ubiquitous process of glycolysis and presents a loop (residues 208-215 of GAPDH) in two alternative conformations (I and II). It is uncertain what triggers this loop rearrangement, as well as which is the precise site from which phosphate attacks the thioacyl intermediate precursor of 1,3-bisphosphoglycerate (BPG). To clarify these uncertainties, we determined the crystal structures of complexes of wild-type GAPDH (WT) with NAD and phosphate or G3P, and of essentially inactive GAPDH mutants (C150S, H177A), trapping crystal structures for the thioacyl intermediate or for ternary complexes with NAD and either phosphate, BPG, or G3P.
View Article and Find Full Text PDFActa Pharmacol Sin
February 2022
Drug Discovery and Design Center, the Center for Chemical Biology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
Aerobic glycolysis, also known as the Warburg effect, is a hallmark of cancer cell glucose metabolism and plays a crucial role in the activation of various types of immune cells. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) catalyzes the conversion of D-glyceraldehyde 3-phosphate to D-glycerate 1,3-bisphosphate in the 6th critical step in glycolysis. GAPDH exerts metabolic flux control during aerobic glycolysis and therefore is an attractive therapeutic target for cancer and autoimmune diseases.
View Article and Find Full Text PDFActa Crystallogr F Struct Biol Commun
September 2020
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai 200438, People's Republic of China.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key enzyme in the glycolytic pathway that catalyzes the conversion of D-glyceraldehyde 3-phosphate to 1,3-diphosphoglycerate. Here, the full-length GAPDH type 1 from Escherichia coli (EcGAPDH1) was cloned and overexpressed, and the protein was purified. Biochemical analyses found that the optimum reaction temperature and pH of EcGAPDH1 were 55°C and 10.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!