HK1
HK1 (hexokinase 1, also written HKI) is a ubiquitous hexokinase that phosphorylates glucose to glucose 6-phosphate, the first step of glycolysis. It localises to the outer mitochondrial membrane and also acts as a pattern recognition receptor for bacterial peptidoglycan. Browse Assay Genie's current range of HK1 research reagents below, or read on for the biology behind the target.
HK1 catalyses the phosphorylation of several hexoses, including D-glucose, D-glucosamine, D-fructose, D-mannose and 2-deoxy-D-glucose, to the corresponding hexose 6-phosphate. It does not phosphorylate N-acetyl-D-glucosamine. By converting D-glucose to D-glucose 6-phosphate, HK1 mediates the initial step of glycolysis, and hexokinases in general produce the glucose-6-phosphate that feeds most glucose metabolism pathways.
Beyond metabolism, HK1 is involved in innate immunity and inflammation. It acts as a pattern recognition receptor for bacterial peptidoglycan. When the N-acetyl-D-glucosamine component of peptidoglycan reaches the cytosol, it inhibits the hexokinase activity of HK1 and causes the enzyme to dissociate from the outer mitochondrial membrane. This release activates the NLRP3 inflammasome.
The HK1 gene encodes a ubiquitous form of hexokinase that localises to the outer membrane of mitochondria, and the protein is also found in the cytosol. Alternative splicing produces several transcript variants encoding different isoforms, some of which are tissue-specific. Mutations in the gene have been associated with haemolytic anaemia due to hexokinase deficiency. HK1 belongs to the hexokinase family, which also includes HK2 and HK3. Mouse and rat both carry an orthologous Hk1 gene, so the HK1 protein can be studied in common rodent models.
HK1 phosphorylates glucose to glucose 6-phosphate, the first step in most glucose metabolism pathways, making it a key enzyme for studying glycolytic flux.
HK1 senses bacterial peptidoglycan as a pattern recognition receptor, linking its release from mitochondria to NLRP3 inflammasome activation.
HK1 localises to the outer mitochondrial membrane and can dissociate into the cytosol, which makes its localisation a useful readout of enzyme state.
Mutations in the HK1 gene are associated with haemolytic anaemia due to hexokinase deficiency, a focus for red cell metabolism research.
HK1 phosphorylates hexoses such as D-glucose, D-fructose and D-mannose to their 6-phosphate forms, and catalyses the first step of glycolysis. It also acts as a pattern recognition receptor for bacterial peptidoglycan, which can lead to NLRP3 inflammasome activation.
HK1 is the HGNC symbol for hexokinase 1, with HKI as an alias; UniProt names the protein Hexokinase-1. Alternative splicing gives several transcript variants encoding different isoforms, and some of these isoforms are tissue-specific.
Mouse and rat both have an orthologous Hk1 gene. In humans, mutations in HK1 have been associated with haemolytic anaemia due to hexokinase deficiency. Check the datasheet of any product for its validated reactivity.
Other hexokinase family members that phosphorylate glucose at the start of glycolysis.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P19367; product specifications from Assay Genie datasheets.