Hexokinase-1 (hexokinase type I, HK I, brain form hexokinase, HK1)

Function

• carbohydrate metabolism, hexose metabolism
• allosteric enzyme inhibited by its product Glc-6-P

ATP + D-hexose <--> ADP + D-hexose 6-phosphate

Structure

• monomer
• N- & C-terminal halves show extensive sequence similarity to each other
• catalytic activity is associated with the C-terminus
• regulatory function is associated with the N-terminus hydrophobic N-terminal sequence may be involved in membrane binding
• belongs to the hexokinase family

Compartment

• mitochondrial outer membrane

Alternative splicing

named isoforms=4

Expression

• isoform 2 is erythrocyte specific
• isoform 3 & isoform 4 are testis-specific

Pathology

• defects in HK1 are the cause of hexokinase deficiency

Notes

• in vertebrates there are 4 major glucose-phosphorylating isoenzymes, designated hexokinase 1, 2, 3 & 4 (glucokinase)

More general terms

• hexokinase
• mitochondrial membrane protein

Database

• OMIM: https://mirror.omim.org/entry/142600
• OMIM: https://mirror.omim.org/entry/235700
• UniProt: http://www.uniprot.org/uniprot/P19367.html