threonine aldolase
{{Short description|Class of enzymes}}
{{infobox enzyme
| Name = threonine aldolase
| EC_number = 4.1.2.5
| CAS_number = 62213-23-4
| GO_code = 0004793
| image = 1lw4.jpg
| width = 270
| caption = L-Threonine aldolase homotetramer, Thermotoga maritima
}}
{{infobox protein
|name=threonine aldolase 1 pseudogene
|caption=
|image=
|width=
|HGNCid=18004
|Symbol=THA1P
|AltSymbols=
|EntrezGene=390816
|OMIM=
|RefSeq=XM_372682
|UniProt=
|PDB=
|ECnumber=
|Chromosome=17
|Arm=q
|Band=25.3
|LocusSupplementaryData=
}}
The enzyme threonine aldolase ({{EnzExplorer|4.1.2.5}}) is an enzyme that catalyzes the chemical reaction
:L-threonine glycine + acetaldehyde
This enzyme belongs to the family of lyases, specifically the aldehyde-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is L-threonine acetaldehyde-lyase (glycine-forming). This enzyme is also called L-threonine acetaldehyde-lyase. This enzyme participates in glycine, serine and threonine metabolism. It employs one cofactor, pyridoxal phosphate.
Structural studies
As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes {{PDB link|1JG8}}, {{PDB link|1LW4}}, {{PDB link|1LW5}}, {{PDB link|1M6S}}, and {{PDB link|1SVV}}.
Presence in human and mouse
The enzyme is synthesized and functional in mice.[https://rd.springer.com/article/10.1186/1471-2164-6-32 Alasdair J Edgar (2005)] Mice have a transcribed L-threonine aldolase/GLY1 gene, but the human GLY1 gene is a non-processed pseudogene. BMC Genomics March 2005, 6:32. [https://rd.springer.com/content/pdf/10.1186%2F1471-2164-6-32 pdf]
Humans also have the remnants of the gene, coding this enzyme (GLY1), however it is damaged by past mutations and inactive. Human gene contains two single nucleotide deletions causing frameshifts and premature stop codons. Also, the encoded protein would not be active anyway due mutations in other highly conserved regions. Human gene is no longer transcribed into RNA.
References
{{Reflist}}
- {{cite journal |author1 = Bell SC |author2 =Turner JM | year = 1973 | title = Bacterial threonine aldolase and serine hydroxymethyltransferase enzyme | journal = Biochem. Soc. Trans. | volume = 1 |issue =3 | pages = 678–681 |doi =10.1042/bst0010678 }}
- {{cite journal | vauthors = KARASEK MA, GREENBERG DM | year = 1957 | title = Studies on the properties of threonine aldolases | journal = J. Biol. Chem. | volume = 227 | pages = 191–205 | pmid = 13449064 | issue = 1 | doi = 10.1016/S0021-9258(18)70806-5 | doi-access = free }}
- {{cite journal | vauthors = Kumagai H, Nagate T, Yoshida H, Yamada H | year = 1972 | title = Threonine aldolase from Candida humicola. II. Purification, crystallization and properties | journal = Biochim. Biophys. Acta | volume = 258 | pages = 779–90 | pmid = 5017702 | issue = 3 | doi=10.1016/0005-2744(72)90179-9}}
{{Amino acid metabolism enzymes}}
{{Carbon-carbon lyases}}
{{Enzymes}}
{{Portal bar|Biology|border=no}}
Category:Pyridoxal phosphate enzymes
Category:Enzymes of known structure
{{4.1-enzyme-stub}}