EC 2.3.1.156     
Accepted name: phloroisovalerophenone synthase
Reaction: (1) isovaleryl-CoA + 3 malonyl-CoA = 4 CoA + 3 CO2 + phlorisovalerophenone
(2) isobutyryl-CoA+ 3 malonyl-CoA = 4 CoA + 3 CO2 + phlorisobutyrophenone
Glossary: phlorisobutyrophenone = 2-methyl-1-(2,4,6-trihydroxyphenyl)propan-1-one
phlorisovalerophenone = 3-methyl-1-(2,4,6-trihydroxyphenyl)butan-1-one
Other name(s): valerophenone synthase; 3-methyl-1-(trihydroxyphenyl)butan-1-one synthase; acylphloroglucinol synthase; isovaleryl-CoA:malonyl-CoA acyltransferase
Systematic name: acyl-CoA:malonyl-CoA acyltransferase
Comments: Closely related to EC 2.3.1.74, naringenin-chalcone synthase. Also acts on isobutyryl-CoA as substrate to give phlorisobutyrophenone. The products are intermediates in the biosynthesis of the bitter acids in hops (Humulus lupulus) and glucosides in strawberry (Fragaria X ananassa). It is also able to generate naringenin chalcone from 4-coumaroyl-CoA.
References:
1.  Fung, S.Y., Zuurbier, K.W.M., Paniego, N.B., Scheffer, J.J.C. and Verpoorte, R. Enzymes from the biosynthesis of hop α and β acids. Proc. 26th Congr. Eur. Brew. Conv. (1997) 215–221.
2.  Zuurbier, K.W.M., Leser, J., Berger, T., Hofte, A.J.P., Schroder, G., Verpoorte, R. and Schroder, J. 4-Hydroxy-2-pyrone formation by chalcone and stilbene synthase with nonphysiological substrates. Phytochemistry 49 (1998) 1945–1951. [PMID: 9883590]
3.  Song, C., Ring, L., Hoffmann, T., Huang, F.C., Slovin, J. and Schwab, W. Acylphloroglucinol biosynthesis in strawberry fruit. Plant Physiol. 169 (2015) 1656–1670. [PMID: 26169681]
[EC 2.3.1.156 created 2000]
 
 
EC 2.4.1.358     
Accepted name: acylphloroglucinol glucosyltransferase
Reaction: UDP-α-D-glucose + 2-acylphloroglucinol = UDP + 2-acylphloroglucinol 1-O-β-D-glucoside
Glossary: phlorisobutyrophenone = 2-methyl-1-(2,4,6-trihydroxyphenyl)propan-1-one
phlorisovalerophenone = 3-methyl-1-(2,4,6-trihydroxyphenyl)butan-1-one
Other name(s): UGT71K3
Systematic name: UDP-α-D-glucose:2-acylphloroglucinol 1-O-β-glucosyltransferase
Comments: Isolated from strawberries (Fragaria X ananassa). Acts best on phloroisovalerophenone and phlorobutyrophenone but will also glycosylate many other phenolic compounds. A minor product of the reaction is the 5-O-β-D-glucoside.
References:
1.  Song, C., Zhao, S., Hong, X., Liu, J., Schulenburg, K. and Schwab, W. A UDP-glucosyltransferase functions in both acylphloroglucinol glucoside and anthocyanin biosynthesis in strawberry (Fragaria x ananassa). Plant J. 85 (2016) 730–742. [PMID: 26859691]
[EC 2.4.1.358 created 2018]
 
 


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