lIDH

lIDH is an acronym that appears in scientific literature with more than one possible meaning, depending on the context. It is not a single, universally standardized term in biochemistry, so the intended reference should be inferred from surrounding text or explicitly defined in the source.

One common interpretation is L-iditol dehydrogenase, abbreviated as lIDH in some bacterial and fungal studies. This enzyme oxidizes L-iditol, a sugar alcohol, as part of carbohydrate metabolism. Enzymes in this family typically rely on NAD+ or NADP+ as cofactors and are involved in pathways that process sugar alcohols and related intermediates. The gene encoding this activity is often named l-idh in genomic annotations. lIDH is usually discussed in the context of microbial metabolism rather than higher eukaryotic central metabolism.

In other contexts, lIDH may be a typographical or interpretive variant of IDH, the widely used abbreviation for isocitrate dehydrogenase. IDH refers to a family of enzymes that catalyze the oxidative decarboxylation of isocitrate to alpha-ketoglutarate in the citric acid cycle and related metabolic pathways. In humans and many organisms, IDH exists as multiple isoforms, including NADP+-dependent IDH1 (cytosolic), IDH2 (mitochondrial), and NAD+-dependent IDH3 (mitochondrial). These enzymes contribute to cellular energy production and biosynthetic processes, and certain mutations in IDH isoforms are associated with cancer.

Because lIDH can denote more than one enzyme, readers should verify the exact meaning from the source. When in doubt, consult the primary text for a definition of lIDH and the context in which it is used. See also IDH (isocitrate dehydrogenase) and L-iditol dehydrogenase for related enzymes.