ID   KHSE_NITWN              Reviewed;         326 AA.
AC   Q3SP50;
DT   11-SEP-2007, integrated into UniProtKB/Swiss-Prot.
DT   11-OCT-2005, sequence version 1.
DT   02-SEP-2026, entry version 127.
DE   RecName: Full=Homoserine kinase {ECO:0000255|HAMAP-Rule:MF_00301};
DE            Short=HK {ECO:0000255|HAMAP-Rule:MF_00301};
DE            Short=HSK {ECO:0000255|HAMAP-Rule:MF_00301};
DE            EC=2.7.1.39 {ECO:0000255|HAMAP-Rule:MF_00301};
GN   Name=thrB {ECO:0000255|HAMAP-Rule:MF_00301};
GN   OrderedLocusNames=Nwi_2688;
OS   Nitrobacter winogradskyi (strain ATCC 25391 / DSM 10237 / CIP 104748 /
OS   NCIMB 11846 / Nb-255).
OC   Bacteria; Pseudomonadati; Pseudomonadota; Alphaproteobacteria;
OC   Hyphomicrobiales; Nitrobacteraceae; Nitrobacter.
OX   NCBI_TaxID=323098;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 25391 / DSM 10237 / CIP 104748 / NCIMB 11846 / Nb-255;
RX   PubMed=16517654; DOI=10.1128/aem.72.3.2050-2063.2006;
RA   Starkenburg S.R., Chain P.S.G., Sayavedra-Soto L.A., Hauser L., Land M.L.,
RA   Larimer F.W., Malfatti S.A., Klotz M.G., Bottomley P.J., Arp D.J.,
RA   Hickey W.J.;
RT   "Genome sequence of the chemolithoautotrophic nitrite-oxidizing bacterium
RT   Nitrobacter winogradskyi Nb-255.";
RL   Appl. Environ. Microbiol. 72:2050-2063(2006).
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=L-homoserine + ATP = O-phospho-L-homoserine + ADP + H(+);
CC         Xref=Rhea:RHEA:13985, ChEBI:CHEBI:15378, ChEBI:CHEBI:30616,
CC         ChEBI:CHEBI:57476, ChEBI:CHEBI:57590, ChEBI:CHEBI:456216;
CC         EC=2.7.1.39; Evidence={ECO:0000255|HAMAP-Rule:MF_00301};
CC   -!- PATHWAY: Amino-acid biosynthesis; L-threonine biosynthesis; L-threonine
CC       from L-aspartate: step 4/5. {ECO:0000255|HAMAP-Rule:MF_00301}.
CC   -!- SIMILARITY: Belongs to the pseudomonas-type ThrB family.
CC       {ECO:0000255|HAMAP-Rule:MF_00301}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; CP000115; ABA05941.1; -; Genomic_DNA.
DR   RefSeq; WP_011315887.1; NC_007406.1.
DR   AlphaFoldDB; Q3SP50; -.
DR   SMR; Q3SP50; -.
DR   STRING; 323098.Nwi_2688; -.
DR   KEGG; nwi:Nwi_2688; -.
DR   eggNOG; COG2334; Bacteria.
DR   HOGENOM; CLU_053300_1_0_5; -.
DR   OrthoDB; 9777460at2; -.
DR   UniPathway; UPA00050; UER00064.
DR   Proteomes; UP000002531; Chromosome.
DR   GO; GO:0004413; F:homoserine kinase activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0009088; P:L-threonine biosynthetic process; IEA:UniProtKB-UniRule.
DR   CDD; cd05153; HomoserineK_II; 1.
DR   Gene3D; 3.90.1200.10; -; 1.
DR   Gene3D; 3.30.200.20; Phosphorylase Kinase, domain 1; 1.
DR   HAMAP; MF_00301; Homoser_kinase_2; 1.
DR   InterPro; IPR002575; Aminoglycoside_PTrfase.
DR   InterPro; IPR005280; Homoserine_kinase_II.
DR   InterPro; IPR011009; Kinase-like_dom_sf.
DR   InterPro; IPR050249; Pseudomonas-type_ThrB.
DR   NCBIfam; NF003558; PRK05231.1; 1.
DR   NCBIfam; TIGR00938; thrB_alt; 1.
DR   PANTHER; PTHR21064:SF6; AMINOGLYCOSIDE PHOSPHOTRANSFERASE DOMAIN-CONTAINING PROTEIN; 1.
DR   PANTHER; PTHR21064; AMINOGLYCOSIDE PHOSPHOTRANSFERASE DOMAIN-CONTAINING PROTEIN-RELATED; 1.
DR   Pfam; PF01636; APH; 1.
DR   SUPFAM; SSF56112; Protein kinase-like (PK-like); 1.
PE   3: Inferred from homology;
KW   Amino-acid biosynthesis; ATP-binding; Kinase; Nucleotide-binding;
KW   Reference proteome; Threonine biosynthesis; Transferase.
FT   CHAIN           1..326
FT                   /note="Homoserine kinase"
FT                   /id="PRO_0000300796"
SQ   SEQUENCE   326 AA;  35859 MW;  07DF1E2435B0FE5E CRC64;
     MAVYTDVAAE ELADFLKAYD IGELLSYKGI AEGVENSNYL LHTTSGSFFL TLYEKRVAID
     DLPFFLGLMG HLATHGIVCP QPVRTRNGET LGSLAGRPAA IIDFLEGVWP RKPNVAHCAA
     VGAALAKLHL AGRDFSMRRA NALSVWSWRP LFEQAGACAD TVQPGLHDFL KAELDHLEAR
     WPQELPGGVI HADLFPDNVL FLGDRLSGLI DFYFACHDFF AYDVAICLNA WCFEPDHAFN
     VTKARALLGA YHRERALSEA EQAALPLLAR GAALRFLLTR LVDFLNVPAG ALVKPKDPLE
     YVRKLRFQQR VGGVRDYGVA ILGPVA
//