P00547 (KHSE_ECOLI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Homoserine kinase
Short name=HK
Short name=HSK
EC=2.7.1.39

Gene names

Name:	thrB
Ordered Locus Names:	b0003, JW0002

Organism

Escherichia coli (strain K12) [Reference proteome] [HAMAP]

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia › Escherichia coli

Protein attributes

Sequence length	310 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Catalyzes the ATP-dependent phosphorylation of L-homoserine to L-homoserine phosphate. Is also able to phosphorylate the hydroxy group on gamma-carbon of L-homoserine analogs when the functional group at the alpha-position is a carboxyl, an ester, or even a hydroxymethyl group. Neither L-threonine nor L-serine are substrates of the enzyme. Ref.7
Catalytic activity	ATP + L-homoserine = ADP + O-phospho-L-homoserine. Ref.7
Pathway	Amino-acid biosynthesis; L-threonine biosynthesis; L-threonine from L-aspartate: step 4/5. HAMAP-Rule MF_00384
Subcellular location	Cytoplasm Probable HAMAP-Rule MF_00384.
Sequence similarities	Belongs to the GHMP kinase family. Homoserine kinase subfamily.
Biophysicochemical properties	Kinetic parameters: The catalytic efficiency is 500-fold higher with L-homoserine than with D-homoserine as substrate. KM=0.14 mM for L-homoserine Ref.7 KM=31.8 mM for D-homoserine KM=0.13 mM for ATP

Ontologies

Keywords
Biological process	Amino-acid biosynthesis Threonine biosynthesis
Cellular component	Cytoplasm
Ligand	ATP-binding Nucleotide-binding
Molecular function	Kinase Transferase
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	threonine biosynthetic process Inferred from mutant phenotype PubMed 4148765PubMed 4364333. Source: EcoCyc
Cellular_component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	ATP binding Inferred from electronic annotation. Source: HAMAP homoserine kinase activity Inferred from direct assay PubMed 177283. Source: EcoCyc
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 310	310	Homoserine kinase HAMAP-Rule MF_00384		PRO_0000156567
Regions
	Nucleotide binding	91 – 101	11	ATP Potential
Experimental info
	Mutagenesis	139	1	H → L: 35-fold decrease in kinase activity. Ref.7
	Mutagenesis	203	1	H → L: 2-fold decrease in kinase activity but nearly no change in substrates affinity. Ref.7
	Mutagenesis	206	1	H → Q: 3500-fold decrease in kinase activity. Ref.7
	Mutagenesis	235	1	R → H: 250-fold decrease in kinase activity but no change in substrates affinity. Ref.7
	Mutagenesis	235	1	R → L: 26200-fold decrease in catalytic efficiency. Ref.7

Sequences

	Sequence		Length	Mass (Da)
	P00547 [UniParc]. Last modified April 1, 1993. Version 2. Checksum: 0F225F9F1B634BE8	FASTA	310	33,624
	10 20 30 40 50 60 MVKVYAPASS ANMSVGFDVL GAAVTPVDGA LLGDVVTVEA AETFSLNNLG RFADKLPSEP 70 80 90 100 110 120 RENIVYQCWE RFCQELGKQI PVAMTLEKNM PIGSGLGSSA CSVVAALMAM NEHCGKPLND 130 140 150 160 170 180 TRLLALMGEL EGRISGSIHY DNVAPCFLGG MQLMIEENDI ISQQVPGFDE WLWVLAYPGI 190 200 210 220 230 240 KVSTAEARAI LPAQYRRQDC IAHGRHLAGF IHACYSRQPE LAAKLMKDVI AEPYRERLLP 250 260 270 280 290 300 GFRQARQAVA EIGAVASGIS GSGPTLFALC DKPETAQRVA DWLGKNYLQN QEGFVHICRL 310 DTAGARVLEN

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Nucleotide sequence of the thrB gene of E. coli, and its two adjacent regions; the thrAB and thrBC junctions." Cossart P., Katinka M., Yaniv M. Nucleic Acids Res. 9:339-347(1981) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]	"Update on the nucleotide sequence of the thrB gene of E. coli." Deborde D.C., Strange J.C., Wright B.E. Submitted (MAY-1993) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], SEQUENCE REVISION TO 166-190.
[3]	"Systematic sequencing of the Escherichia coli genome: analysis of the 0-2.4 min region." Yura T., Mori H., Nagai H., Nagata T., Ishihama A., Fujita N., Isono K., Mizobuchi K., Nakata A. Nucleic Acids Res. 20:3305-3308(1992) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12.
[4]	"Analysis of the Escherichia coli genome VI: DNA sequence of the region from 92.8 through 100 minutes." Burland V.D., Plunkett G. III, Sofia H.J., Daniels D.L., Blattner F.R. Nucleic Acids Res. 23:2105-2119(1995) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[5]	"The complete genome sequence of Escherichia coli K-12." Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., Shao Y. Science 277:1453-1474(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[6]	"Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110." Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T. Mol. Syst. Biol. 2:E1-E5(2006) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA], SEQUENCE REVISION. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[7]	"Substrate specificity and identification of functional groups of homoserine kinase from Escherichia coli." Huo X., Viola R.E. Biochemistry 35:16180-16185(1996) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION AS A HOMOSERINE KINASE, CATALYTIC ACTIVITY, SUBSTRATE SPECIFICITY, KINETIC PARAMETERS, MUTAGENESIS OF HIS-139; HIS-203; HIS-206 AND ARG-235.

Cross-references

Sequence databases
EMBL GenBank DDBJ	L13601 Genomic DNA. Translation: AAA20618.1. U14003 Genomic DNA. Translation: AAA97302.1. U00096 Genomic DNA. Translation: AAC73114.1. AP009048 Genomic DNA. Translation: BAB96580.2.
PIR	KIECM. S56630.
RefSeq	NP_414544.1. NC_000913.2. YP_488309.1. NC_007779.1.
3D structure databases
ProteinModelPortal	P00547.
SMR	P00547. Positions 2-290.
ModBase	Search...
Protein-protein interaction databases
IntAct	P00547. 2 interactions.
STRING	511145.b0003.
2D gel databases
SWISS-2DPAGE	P00547.
Proteomic databases
PaxDb	P00547.
PRIDE	P00547.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
EnsemblBacteria	AAC73114; AAC73114; b0003. BAB96580; BAB96580; BAB96580.
GeneID	12932940. 947498.
KEGG	ecj:Y75_p0003. eco:b0003.
PATRIC	32115101. VBIEscCol129921_0002.
Organism-specific databases
EchoBASE	EB0992.
EcoGene	EG10999. thrB.
Phylogenomic databases
eggNOG	COG0083.
HOGENOM	HOG000247198.
KO	K00872.
OMA	GFVHICK.
ProtClustDB	PRK01212.
Enzyme and pathway databases
BioCyc	EcoCyc:HOMOSERKIN-MONOMER. ECOL316407:JW0002-MONOMER. MetaCyc:HOMOSERKIN-MONOMER.
UniPathway	UPA00050; UER00064.
Gene expression databases
Genevestigator	P00547.
Family and domain databases
Gene3D	3.30.230.10. 1 hit.
HAMAP	MF_00384. Homoser_kinase.
InterPro	IPR013750. GHMP_kinase_C_dom. IPR006204. GHMP_kinase_N_dom. IPR006203. GHMP_knse_ATP-bd_CS. IPR000870. Homoserine_kinase. IPR020568. Ribosomal_S5_D2-typ_fold. IPR014721. Ribosomal_S5_D2-typ_fold_subgr. [Graphical view]
Pfam	PF08544. GHMP_kinases_C. 1 hit. PF00288. GHMP_kinases_N. 1 hit. [Graphical view]
PIRSF	PIRSF000676. Homoser_kin. 1 hit.
PRINTS	PR00958. HOMSERKINASE.
SUPFAM	SSF54211. Ribosomal_S5_D2-typ_fold. 1 hit.
TIGRFAMs	TIGR00191. thrB. 1 hit.
PROSITE	PS00627. GHMP_KINASES_ATP. 1 hit. [Graphical view]
ProtoNet	Search...
Other
BindingDB	P00547.

Entry information

Entry name

KHSE_ECOLI

Accession

Primary (citable) accession number: P00547

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	April 1, 1993
Last modified:	May 1, 2013
This is version 124 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program