2B9X

Crystal Structure of CLA-producing fatty acid isomerase from P. acnes

Summary for 2B9X

• Entry DOI: 10.2210/pdb2b9x/pdb
• Related: 2B9W 2B9Y 2BA9 2BAB 2BAC
• Descriptor: putative aminooxidase, SODIUM ION, SULFATE ION, ... (7 entities in total)
• Functional Keywords: isomerase, conjugated linoleic acid, fad
• Biological source: Propionibacterium acnes
• Total number of polymer chains: 1
• Total formula weight: 51929.10

Authors

Rudolph, M.G.,Liavonchanka, A. (deposition date: 2005-10-13, release date: 2006-01-31, Last modification date: 2024-03-13)

Primary citation

Liavonchanka, A.,Hornung, E.,Feussner, I.,Rudolph, M.G.
Structure and mechanism of the Propionibacterium acnes polyunsaturated fatty acid isomerase
Proc.Natl.Acad.Sci.Usa, 103:2576-2581, 2006

PubMed Abstract: Conjugated linoleic acids (CLAs) affect body fat gain, carcinogenesis, insulin resistance, and lipid peroxidation in mammals. Several isomers of CLA exist, of which the (9Z, 11E) and (10E, 12Z) isomers have beneficial effects on human metabolism but are scarce in foods. Bacterial polyunsaturated fatty acid isomerases are promising biotechnological catalysts for CLA production. We describe six crystal structures of the Propionibacterium acnes polyunsaturated fatty acid isomerase PAI in apo- and product-bound forms. The three-domain flavoprotein has previously undescribed folds outside the FAD-binding site. Conformational changes in a hydrophobic channel toward the active site reveal a unique gating mechanism for substrate specificity. The geometry of the substrate-binding site explains the length preferences for C18 fatty acids. A catalytic mechanism for double-bond isomerization is formulated that may be altered to change substrate specificity for syntheses of rare CLAs from easily accessible precursors.

PubMed: 16477020
DOI: 10.1073/pnas.0510144103

Experimental method

X-RAY DIFFRACTION (2.22 Å)