Reviewed, UniProtKB/Swiss-Prot O64390 (HXK1_SOLTU)

Names and origin

Protein names

Recommended name:
    Hexokinase-1
    EC=2.7.1.1
Alternative name(s):
    StHK1

Gene names

Name:	HXK1
Synonyms:	HXK

Organism

Solanum tuberosum (Potato)

Taxonomic identifier

4113 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › lamiids › Solanales › Solanaceae › Solanoideae › Solaneae › Solanum

Protein attributes

Sequence length	498 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Fructose and glucose phosphorylating enzyme. May be involved in the phosphorylation of glucose during the export from plastids to cytosol. Seems neither to be involved in cell sugar sensing nor in carbohydrate metabolism in tuber. Ref.2
Catalytic activity	ATP + D-hexose = ADP + D-hexose 6-phosphate.
Subcellular location	Plastid › chloroplast outer membrane; Single-pass membrane protein By similarity.
Tissue specificity	Expressed in young and mature leaves, stems, roots, stolons, and developing and mature tubers. Ref.2
Sequence similarities	Belongs to the hexokinase family.
Biophysicochemical properties	Kinetic parameters: Measured in yeast lacking glucose and hexose kinase activity. KM=0.033 mM for glucose KM=1.470 mM for fructose KM=0.029 mM for mannose Vmax=349 nmol/min/mg enzyme with glucose as substrate Vmax=523 nmol/min/mg enzyme with fructose as substrate Vmax=221 nmol/min/mg enzyme with mannose as substrate

Ontologies

Keywords
Biological process	Glycolysis
Cellular component	Chloroplast Membrane Plastid Plastid outer membrane
Domain	Transmembrane
Ligand	ATP-binding Nucleotide-binding
Molecular function	Kinase Transferase
Gene Ontology (GO)
Biological process	glycolysis Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	chloroplast Inferred from electronic annotation. Source: UniProtKB-KW integral to membrane Inferred from electronic annotation. Source: UniProtKB-SubCell plastid outer membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	ATP binding Inferred from electronic annotation. Source: UniProtKB-KW hexokinase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 498	498	Hexokinase-1		PRO_0000197615
Regions
	Transmembrane	4 – 24	21	Potential
	Nucleotide binding	101 – 106	6	ATP Potential
	Region	171 – 197	27	Glucose-binding Potential

Sequences

	Sequence		Length	Mass (Da)
	O64390-1 [UniParc]. Last modified August 1, 1998. Version 1. Checksum: D7F598CBB12762E4	FASTA	498	54,130
	10 20 30 40 50 60 MKKVTVGAAV VGAAAVCAVA ALIVNHRMRK SSKWGRAMAI LREFEEKCKT QDAKLKQVAD 70 80 90 100 110 120 AMTVEMHAGL ASEGGQSSRC LSPMSIISQL VMKLGVFYAL DLGGTNFRVL RVQLGGKDGG 130 140 150 160 170 180 IIHQEFAEAS IPPSLMVGTS DALFDYIAAE LAKFVAAEEE KFHQPPGKQR ELGFHLLIPS 190 200 210 220 230 240 NADFNNSGTI MRWTKGFSID DAVGQDVVGE LTKAMKEKVL DMRVSALVND TVGTLAGGKY 250 260 270 280 290 300 TQKDVAVAVI LGTGTNAAYV ERVQAIPKWH GPVPKSGEMV INMEWGNFRS SHLPLTEYDH 310 320 330 340 350 360 ALDNESLNPA EQIFEKMTSG MYLGEILRRV LTRVAEEVLA FLAMRSLQSL KDSFVLRTPD 370 380 390 400 410 420 MSAMHHDTSP DLKVVGEKLK DILEISNTSL KTRKLVLSLC NIVATRGARL DAAGVLGILK 430 440 450 460 470 480 KMGRDTPKQG GSERTVIAMD GGLYEHYTEY RMCLENSLKD LLGEELATSI VFVHSNDGSG 490 IGAALLRASH SMYLEDQA

References

[1]	Clericus M., Heins L., Schmitz U.K. Submitted (DEC-1995) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Desiree. Tissue: Leaf.
[2]	"Antisense repression of hexokinase 1 leads to an overaccumulation of starch in leaves of transgenic potato plants but not to significant changes in tuber carbohydrate metabolism." Veramendi J., Roessner U., Renz A., Willmitzer L., Trethewey R.N. Plant Physiol. 121:123-134(1999) [PubMed: 10482667] [Abstract] Cited for: FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, TISSUE SPECIFICITY.

Cross-references

Sequence databases
EMBLGenBankDDBJ	X94302 mRNA. Translation: CAA63966.1.
PIR	T07384.
3D structure databases
HSSP	HSSP built from PDB template 1IG8 based on UniProtKB P04807.
ModBase	Search...
Enzyme and pathway databases
BRENDA	2.7.1.1. 296.
Family and domain databases
InterPro	IPR001312. Hexokinase. IPR019807. Hexokinase_CS. [Graphical view]
PANTHER	PTHR19443. Hexokinase. 1 hit.
Pfam	PF00349. Hexokinase_1. 1 hit. PF03727. Hexokinase_2. 1 hit. [Graphical view]
PRINTS	PR00475. HEXOKINASE.
ProDom	PD001109. Hexokinase. 1 hit. [Graphical view] [Entries sharing at least one domain]
PROSITE	PS00378. HEXOKINASES. False negative. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

HXK1_SOLTU

Accession

Primary (citable) accession number: O64390

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 1, 2000
Last sequence update:	August 1, 1998
Last modified:	October 13, 2009
This is version 56 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)