| Purification and Quality Control | The His-tag recombinant protein is purified by affinity chromatography in combination with FPLC columns. The purified L-GLK (isoform 3) is greater than 95% homogeneous based on SDS-PAGE analysis. |
| Unit Definition (Activity) | 1 unit equals 1 nanogram of purified protein. |
| Applications | Can be used for the phosphorylation of Glucose, assay development. |
| Formulation and Storage | The protein is in 20mM Tris-HCl pH7.9,100mM NaCl, 0.2mM EDTA, 1mM DTT and 20% glycerol. Stored at -70°C before use. Avoid repeated freeze thaw cycles. |
| Synonym | Homo sapiens glucokinase (hexokinase 4) (GCK), transcript variant 3; FGQTL3; GK; GLK; HHF3; HK4; HKIV; HXKP; LGLK and MODY2. |
| Protein Sequence | MPRPRSQLPQ PNSQVEQILA EFQLQEEDLK KVMRRMQKEM DRGLRLETHE EASVKMLPTY
VRSTPEGSEV GDFLSLDLGG TNFRVMLVKV GEGEEGQWSV KTKHQMYSIP EDAMTGTAEM
LFDYISECIS DFLDKHQMKH KKLPLGFTFS FPVRHEDIDK GILLNWTKGF KASGAEGNNV
VGLLRDAIKR RGDFEMDVVA MVNDTVATMI SCYYEDHQCE VGMIVGTGCN ACYMEEMQNV
ELVEGDEGRM CVNTEWGAFG DSGELDEFLL EYDRLVDESS ANPGQQLYEK LIGGKYMGEL
VRLVLLRLVD ENLLFHGEAS EQLRTRGAFE TRFVSQVESD TGDRKQIYNI LSTLGLRPST
TDCDIVRRAC ESVSTRAAHM CSAGLAGVIN RMRESRSEDV MRITVGVDGS VYKLHPSFKE
RFHASVRRLT PSCEITFIES EEGSGRGAAL VSAVACKKAC MLGQ |
| Background | The phosphorylation of glucose at the sixth carbon position is the first step in glycolysis. Glucokinase is a structurally and functionally unique member of the hexokinase family. Glucokinase is expressed only in mammalian liver and pancreatic islet beta cells. Because of its unique functional characteristics, the enzyme plays an important regulatory role in glucose metabolism. Defects in the glucokinase gene have long been suspected contributors to the genetic susceptibility to noninsulin-dependent diabetes mellitus.(1) It is suggested that mutant GCK leads to chronic hyperglycemia by raising the threshold of circulating glucose levels which induces insulin secretion. (2) Given the central role of glucokinase in the regulation of insulin release, it is understandable that mutations in the GCK gene can cause both hyper- and hypoglycemia. (3)Recently, a novel class of drugs that stimulate the GK molecule directly have been discovered, which offer a new principle for drug therapy of diabetes. (4) |
| References | 1. Matsutani, A. et al, Genomics 12: 319-325, 1992.
2. Velho, G. et al, Lancet 340: 444-448, 1992.
3. Gloyn, A. L., et al. Hum. Mutat. 22: 353-362, 2003.
4. Grimsby, J. et al., Diabetes 50 (Suppl.2), A115, 2001. |
