Histidine ammonia-lyase

(Redirected from Histidase)

Histidine ammonia-lyase (EC 4.3.1.3, histidase, histidinase) is an enzyme that in humans is encoded by the HAL gene.[5][6] It converts histidine into ammonia and urocanic acid. Its systematic name is L-histidine ammonia-lyase (urocanate-forming).

HAL
Identifiers
AliasesHAL, HIS, HSTD, histidine ammonia-lyase, Histidine ammonia-lyase
External IDsOMIM: 609457; MGI: 96010; HomoloGene: 68229; GeneCards: HAL; OMA:HAL - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_001258333
NM_001258334
NM_002108

NM_010401

RefSeq (protein)

NP_001245262
NP_001245263
NP_002099

NP_034531

Location (UCSC)Chr 12: 95.97 – 96 MbChr 10: 93.32 – 93.36 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse
histidine ammonia-lyase
Histidine ammonia-lyase homotetramer, Pseudomonas putida
Identifiers
EC no.4.3.1.3
CAS no.9013-75-6
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Search
PMCarticles
PubMedarticles
NCBIproteins

Function

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Histidine ammonia-lyase is a cytosolic enzyme catalyzing the first reaction in histidine catabolism, the nonoxidative deamination of L-histidine to trans-urocanic acid.[5] The reaction is catalyzed by 3,5-dihydro-5-methyldiene-4H-imidazol-4-one (MIO), an electrophilic cofactor which is formed autocatalytically by cyclization of the protein backbone of the enzyme.[7]

 
Proposed autocatalytic formation of MIO cofactor in another enzyme, phenylalanine ammonia-lyase, from the tripeptide Ala-Ser-Gly by two water elimination steps.

Pathology

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Mutations in the gene for histidase are associated with histidinemia and urocanic aciduria.

See also

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References

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  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000084110Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000020017Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ a b "Entrez Gene: histidine ammonia-lyase".
  6. ^ Suchi M, Sano H, Mizuno H, Wada Y (September 1995). "Molecular cloning and structural characterization of the human histidase gene (HAL)". Genomics. 29 (1): 98–104. doi:10.1006/geno.1995.1219. PMID 8530107.
  7. ^ Schwede TF, Rétey J, Schulz GE (Apr 27, 1999). "Crystal structure of histidine ammonia-lyase revealing a novel polypeptide modification as the catalytic electrophile". Biochemistry. 38 (17): 5355–5361. doi:10.1021/bi982929q. PMID 10220322.

Further reading

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This article incorporates text from the United States National Library of Medicine, which is in the public domain.