L-2-Hydroxyglutarate production arises from noncanonical enzyme function at acidic pH

• Published in: Nature chemical biology Vol. 13; no. 5; pp. 494 - 500
• Main Authors: Intlekofer, Andrew M, Wang, Bo, Liu, Hui, Shah, Hardik, Carmona-Fontaine, Carlos, Rustenburg, Ariën S, Salah, Salah, Gunner, M R, Chodera, John D, Cross, Justin R, Thompson, Craig B
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.05.2017; Nature Publishing Group
• Subjects: 631/1647/296; 631/67; 631/92/1643; 631/92/607; Acidity; Biocatalysis; Biochemical Engineering; Biochemistry; Bioorganic Chemistry; Cell Biology; Cell differentiation; Chemistry; Chemistry/Food Science; Dehydrogenase; Enzymes; Gas Chromatography-Mass Spectrometry; Glutarates - metabolism; Humans; Hydrogen-Ion Concentration; Hypoxia; Ketoglutaric Acids - chemistry; Ketoglutaric Acids - metabolism; L-Lactate Dehydrogenase - metabolism; Malate Dehydrogenase - metabolism; Metabolites; Molecular Structure; Mutation; Stereoisomerism; Substrates; Temperature effects
• ISSN: 1552-4450; 1552-4469
• DOI: 10.1038/nchembio.2307

Acidification enhances lactate dehydrogenase– and malate dehydrogenase–mediated promiscuous production of L -2-hydroxyglutarate ( L -2HG) from α-ketoglutarate and stabilizes HIF-1α levels. The metabolite 2-hydroxyglutarate (2HG) can be produced as either a D- R - or L- S - enantiomer, each of which inhibits α-ketoglutarate (αKG)-dependent enzymes involved in diverse biologic processes. Oncogenic mutations in isocitrate dehydrogenase (IDH) produce D -2HG, which causes a pathologic blockade in cell differentiation. On the other hand, oxygen limitation leads to accumulation of L -2HG, which can facilitate physiologic adaptation to hypoxic stress in both normal and malignant cells. Here we demonstrate that purified lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) catalyze stereospecific production of L -2HG via 'promiscuous' reduction of the alternative substrate αKG. Acidic pH enhances production of L -2HG by promoting a protonated form of αKG that binds to a key residue in the substrate-binding pocket of LDHA. Acid-enhanced production of L -2HG leads to stabilization of hypoxia-inducible factor 1 alpha (HIF-1α) in normoxia. These findings offer insights into mechanisms whereby microenvironmental factors influence production of metabolites that alter cell fate and function.