KYAT1
KYAT1 (kynurenine aminotransferase 1, also known as KATI, GTK and CCBL1) is a cytosolic pyridoxal-phosphate-dependent enzyme. It converts L-kynurenine to kynurenic acid in tryptophan catabolism and metabolises cysteine S-conjugates of certain halogenated compounds. Browse Assay Genie's current range of KYAT1 research reagents below, or read on for the biology behind the target.
KYAT1 catalyses the irreversible transamination of L-kynurenine, a metabolite of L-tryptophan, to form kynurenic acid (KA). KA is an intermediate in the tryptophan catabolic pathway and is also a broad-spectrum antagonist of the three ionotropic excitatory amino acid receptors, among other targets. The enzyme therefore links tryptophan metabolism to the control of excitatory neurotransmission.
The enzyme has a second major activity. It metabolises the cysteine conjugates of certain halogenated alkenes and alkanes to form reactive metabolites, and it catalyses the beta-elimination of S-conjugates and Se-conjugates of L-(seleno)cysteine, cleaving the C-S or C-Se bond. According to the NCBI Gene summary, this metabolism can produce reactive metabolites that lead to nephrotoxicity and neurotoxicity. The KYAT1 gene encodes a cytosolic protein, and multiple transcript variants encoding different isoforms have been identified.
KYAT1 belongs to the class-I pyridoxal-phosphate-dependent aminotransferase family and sits in the HGNC transaminases gene group. Its names reflect its history: it was previously called cysteine conjugate-beta lyase 1 (CCBL1), glutamine transaminase K (GTK) and kynurenine aminotransferase I (KATI). Increased levels of the enzyme have been linked to schizophrenia. Mouse and rat both carry a Kyat1 ortholog, which supports comparative work on the pathway.
KYAT1 converts L-kynurenine to kynurenic acid, so it is a point of study in the tryptophan catabolic pathway.
Kynurenic acid antagonises ionotropic excitatory amino acid receptors, and increased KYAT1 levels have been linked to schizophrenia.
KYAT1 processes cysteine conjugates of halogenated alkenes and alkanes into reactive metabolites associated with nephrotoxicity and neurotoxicity.
As a class-I pyridoxal-phosphate-dependent enzyme, KYAT1 also cleaves S- and Se-conjugates of L-(seleno)cysteine by beta-elimination.
KYAT1 catalyses the irreversible transamination of L-kynurenine to kynurenic acid in tryptophan catabolism. It also metabolises cysteine conjugates of certain halogenated alkenes and alkanes into reactive metabolites, and cleaves C-S or C-Se bonds in S- and Se-conjugates of L-(seleno)cysteine by beta-elimination.
The enzyme was characterised through different activities. KATI reflects kynurenine aminotransferase activity, GTK is glutamine transaminase K, and CCBL1 is cysteine conjugate beta lyase 1. UniProt names it kynurenine--oxoglutarate transaminase 1. Multiple transcript variants encoding different isoforms have also been reported.
Mouse and rat each have a Kyat1 ortholog, so rodent models can be used to study the enzyme. NCBI Gene reports that increased KYAT1 levels have been linked to schizophrenia. Check the datasheet of any product for its validated reactivity.
Other kynurenine pathway enzymes, transaminases and tryptophan metabolism targets with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q16773; product specifications from Assay Genie datasheets.