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MetaCyc Enzyme: oleate 12-hydroxylase

Gene: FAH12 Accession Number: G-11805 (MetaCyc)

Synonyms: G-11792

Species: Ricinus communis

Summary:
A protein having oleoyl-12-hydroxylase activity was purified and characterized from microsomal fraction of immature Ricinus communis (castor bean).

The gene encoding the enzyme was identified from a cDNA library prepared from developing endosperm [vandeLoo95]. The gene, which was named FAH12, is only expressed in developing seeds [Lu07, Brown12]. The gene has 67% identity with Arabodopsis FAD2, which encodes a acyl-lipid ω-6 desaturase (that enzyme functions as oleate 12-desaturase in Arabidopsis), and contains 3 histidine-rich motifs that are conserved across all membrane-bound desaturases [vandeLoo95].

The enzyme, which was found to peak in the late anthesis stage, catalyzed the formation of ricinoleate [vandeLoo95]. A later study used the in vivo substrate, 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine (2-oleoyl-PC) for in vitro characterization, an improvement over previous experiments that used oleoyl-CoA as substrate [Lin96].

The cDNA was recombinantly expressed in transgenic arabidopsis and Nicotiana plants.The enzyme is specificaly expressed in seeds, where ricinoleate accumulates [Broun97].

Molecular Weight of Polypeptide: 44.3 kD (from nucleotide sequence), 44.4 kD (experimental) [Broun97 ]

Unification Links: Entrez-Nucleotide:EU523112 , Entrez:AAC49010 , Entrez:ACD39348 , UniProt:D2CPE1 , UniProt:Q41131

Relationship Links: InterPro:IN-FAMILY:IPR005804 , InterPro:IN-FAMILY:IPR021863 , Pfam:IN-FAMILY:PF00487 , Pfam:IN-FAMILY:PF11960

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Credits:
Created 10-Feb-2010 by Pujar A , Boyce Thompson Institute
Revised 01-Dec-2014 by Caspi R , SRI International


Enzymatic reaction of: oleate 12-hydroxylase

EC Number: 1.14.18.b

a [glycerolipid]-(11Z)-eicosenoate + 2 a ferrocytochrome b5 + oxygen + 2 H+ <=> a [glycerolipid]-lesquerolate + 2 a ferricytochrome b5 + H2O

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

The reaction is physiologically favored in the direction shown.


Enzymatic reaction of: oleate 12-hydroxylase

EC Number: 1.14.18.b

a [glycerolipid]-oleate + 2 a ferrocytochrome b5 + oxygen + 2 H+ <=> a [glycerolipid]-ricinoleate + 2 a ferricytochrome b5 + H2O

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

The reaction is physiologically favored in the direction shown.

In Pathways: ricinoleate biosynthesis


Enzymatic reaction of: oleate 12-hydroxylase

EC Number: 1.14.18.b

a 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine + 2 a ferrocytochrome b5 + oxygen + 2 H+ <=> a 1-acyl-2-[(R)-12-hydroxyoleoyl]-sn-glycero-3-phosphocholine + 2 a ferricytochrome b5 + H2O

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

The reaction is physiologically favored in the direction shown.

In Pathways: ricinoleate biosynthesis

History:
10/1/2014 (caspi) Merged genes G-11792/FAH12 into G-11805/FAH12


References

Broun97: Broun P, Somerville C (1997). "Accumulation of ricinoleic, lesquerolic, and densipolic acids in seeds of transgenic Arabidopsis plants that express a fatty acyl hydroxylase cDNA from castor bean." Plant Physiol 113(3);933-42. PMID: 9085577

Brown12: Brown AP, Kroon JT, Swarbreck D, Febrer M, Larson TR, Graham IA, Caccamo M, Slabas AR (2012). "Tissue-specific whole transcriptome sequencing in castor, directed at understanding triacylglycerol lipid biosynthetic pathways." PLoS One 7(2);e30100. PMID: 22319559

Lin96: Lin JT, McKeon TA, Goodrich-Tanrikulu M, Stafford AE (1996). "Characterization of oleoyl-12-hydroxylase in castor microsomes using the putative substrate, 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine." Lipids 31(6);571-7. PMID: 8784737

Lu07: Lu C, Wallis JG, Browse J (2007). "An analysis of expressed sequence tags of developing castor endosperm using a full-length cDNA library." BMC Plant Biol 7;42. PMID: 17672910

vandeLoo95: van de Loo FJ, Broun P, Turner S, Somerville C (1995). "An oleate 12-hydroxylase from Ricinus communis L. is a fatty acyl desaturase homolog." Proc Natl Acad Sci U S A 92(15);6743-7. PMID: 7624314


Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 19.0 on Mon Jul 6, 2015, biocyc11.