Structural highlights
Function
[CPXB_BACME] Functions as a fatty acid monooxygenase. Catalyzes hydroxylation of medium and long-chain fatty acids at omega-1, omega-2 and omega-3 positions, with optimum chain lengths of 12-16 carbons (lauric, myristic, and palmitic acids). The reductase domain is required for electron transfer from NADP to cytochrome P450.
Publication Abstract from PubMed
This paper reports the structure of the double mutant Asp251Gly/Gln307His (named A2) generated by random mutagenesis, able to produce 4'-hydroxydiclofenac, 2-hydroxyibuprofen and 4-hydroxytolbutamide from diclofenac, ibuprofen and tolbutamide, respectively. The 3D structure of the substrate-free mutant shows a conformation similar to the closed one found in the substrate-bound wild type enzyme, but with a higher degree of disorder in the region of the G-helix and F-G loop. This is due to the mutation Asp251Gly that breaks the salt bridge between Aps251 on I-helix and Lys224 on G-helix, allowing the G-helix to move away from I-helix and conferring a higher degree of flexibility to this element. This subtle structural change is accompanied by long-range structural rearrangements of the active site with the rotation of Phe87 and a reorganization of catalytically important water molecules. The impact of these structural features on thermal stability, reduction potential and electron transfer is investigated. The data demonstrate that a single mutation far from the active site triggers an increase in protein flexibility in a key region, shifting the conformational equilibrium toward the closed form that is ready to accept electrons and enter the P450 catalytic cycle as soon as a substrate is accepted.
Subtle structural changes in the Asp251Gly/Gln307His P450 BM3 mutant responsible for new activity toward diclofenac, tolbutamide and ibuprofen.,Di Nardo G, Dell'Angelo V, Catucci G, Sadeghi SJ, Gilardi G Arch Biochem Biophys. 2015 Dec 21. pii: S0003-9861(15)30116-8. doi:, 10.1016/j.abb.2015.12.005. PMID:26718083[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Di Nardo G, Dell'Angelo V, Catucci G, Sadeghi SJ, Gilardi G. Subtle structural changes in the Asp251Gly/Gln307His P450 BM3 mutant responsible for new activity toward diclofenac, tolbutamide and ibuprofen. Arch Biochem Biophys. 2015 Dec 21. pii: S0003-9861(15)30116-8. doi:, 10.1016/j.abb.2015.12.005. PMID:26718083 doi:https://dx.doi.org/10.1016/j.abb.2015.12.005
