17278-73-8Relevant articles and documents
Regioselective hydroxylation of C12-C15 fatty acids with fluorinated substituents by cytochrome P450 BM3
Chiang, Chih-Hsiang,Ramu, Ravirala,Tu, Yi-Jung,Yang, Chung-Ling,Ng, Kok Yaoh,Luo, Wen-I,Chen, Charles H.,Lu, Yu-Ying,Liu, Chen-Lun,Yu, Steve S.-F.
, p. 13680 - 13691 (2013)
We demonstrate herein that wild-type cytochrome P450 BM3 can recognize non-natural substrates, such as fluorinated C12-C15 chain-length fatty acids, and show better catalysis for their efficient conversion. Although the binding affinities for fluorinated substrates in the P450 BM3 pocket are marginally lower than those for non-fluorinated substrates, spin-shift measurements suggest that fluoro substituents at the ω-position can facilitate rearrangement of the dynamic structure of the bulk-water network within the hydrophobic pocket through a micro desolvation process to expel the water ligand of the heme iron that is present in the resting state. A lowering of the Michaelis-Menten constant (Km), however, indicates that fluorinated fatty acids are indeed better substrates compared with their non-fluorinated counterparts. An enhancement of the turnover frequencies (k cat) for electron transfer from NADPH to the heme iron and for C-H bond oxidation by compound I (Cpd I) to yield the product suggests that the activation energies associated with going from the enzyme-substrate (ES state) to the corresponding transition state (ES≠ state) are significantly lowered for both steps in the case of the fluorinated substrates. Delicate control of the regioselectivity by the fluorinated terminal methyl groups of the C12-C15 fatty acids has been noted. Despite the fact that residues Arg47/Tyr51/Ser72 exert significant control over the hydroxylation of the subterminal carbon atoms toward the hydrocarbon tail, the fluorine substituent(s) at the ω-position affects the regioselective hydroxylation. For substrate hydroxylation, we have found that fluorinated lauric acids probably give a better structural fit for the heme pocket than fluorinated pentadecanoic acid, even though pentadecanoic acid is by far the best substrate among the reported fatty acids. Interestingly, 12-fluorododecanoic acid, with only one fluorine atom at the terminal methyl group, exhibits a comparable turnover frequency to that of pentadecanoic acid. Thus, fluorination of the terminal methyl group introduces additional interactions of the substrate within the hydrophobic pocket, which influence the electron transfers for both dioxygen activation and the controlled oxidation of aliphatics mediated by high-valent oxoferryl species. Regiospecific enzyme catalysis: The unique van der Waals interactions between a fluorine substituent(s) and neighboring residues in the heme pocket of recombinant cytochrome P450 BM3 give rise to excellent regioselective oxidation of substrates such as fluorinated lauric acids and pentadecanoic acid at the ω-3 position (67-100 %; see figure). Copyright
Novel insights into oxidation of fatty acids and fatty alcohols by cytochrome P450 monooxygenase CYP4B1
Thesseling, Florian A.,Hutter, Michael C.,Wiek, Constanze,Kowalski, John P.,Rettie, Allan E.,Girhard, Marco
, (2019/12/12)
CYP4B1 is an enigmatic mammalian cytochrome P450 monooxygenase acting at the interface between xenobiotic and endobiotic metabolism. A prominent CYP4B1 substrate is the furan pro-toxin 4-ipomeanol (IPO). Our recent investigation on metabolism of IPO related compounds that maintain the furan functionality of IPO while replacing its alcohol group with alkyl chains of varying structure and length revealed that, in addition to cytotoxic reactive metabolite formation (resulting from furan activation) non-cytotoxic ω-hydroxylation at the alkyl chain can also occur. We hypothesized that substrate reorientations may happen in the active site of CYP4B1. These findings prompted us to re-investigate oxidation of unsaturated fatty acids and fatty alcohols with C9–C16 carbon chain length by CYP4B1. Strikingly, we found that besides the previously reported ω- and ω-1-hydroxylations, CYP4B1 is also capable of α-, β-, γ-, and δ-fatty acid hydroxylation. In contrast, fatty alcohols of the same chain length are exclusively hydroxylated at ω, ω-1, and ω-2 positions. Docking results for the corresponding CYP4B1-substrate complexes revealed that fatty acids can adopt U-shaped bonding conformations, such that carbon atoms in both arms may approach the heme-iron. Quantum chemical estimates of activation energies of the hydrogen radical abstraction by the reactive compound 1 as well as electron densities of the substrate orbitals led to the conclusion that fatty acid and fatty alcohol oxidations by CYP4B1 are kinetically controlled reactions.
Selective ?-1 oxidation of fatty acids by CYP147G1 from Mycobacterium marinum
Child, Stella A.,Rossi, Vanessa P.,Bell, Stephen G.
, p. 408 - 417 (2018/12/11)
Background: Cyp147G1 is one of 47 cytochrome P450 encoding genes in Mycobacterium marinum M, a pathogenic bacterium with a high degree of sequence similarity to Mycobacterium tuberculosis and Mycobacterium ulcerans. Cyp147G1 is one of only two of these cyp genes which are closely associated with a complete electron transfer system. Methods: The substrate range of the enzyme was tested in vitro and the activity of CYP147G1 was reconstituted in vivo by co-producing the P450 with the ferredoxin and ferredoxin reductase. Results: Substrates of CYP147G1 include fatty acids ranging from octanoic to hexadecanoic acid. CYP147G1 catalysed the selective hydroxylation of linear and ω-2 methyl branched fatty acids at the ω-1 position (≥ 98%). Oxidation of ω-1 methyl branched fatty acids generated the ω and ω-1 hydroxylation products in almost equal proportions, indicating altered position of hydrogen abstraction. Conclusions: This selectivity of fatty acid hydroxylation inferred that linear species must bind in the active site of the enzyme with the terminal methyl group sequestered so that abstraction at the C–H bonds of the ω-1 position is favoured. With branched substrates, one of the methyl groups must be close to the compound I oxygen atom and enable hydroxylation at the terminal methyl group to compete with the reaction at the ω-1C–H bond. General significance: Hydroxy fatty acids are widely used for industrial, food and medical purposes. CYP147G1 demonstrates high regioselectivity for hydroxylation at a sub-terminal position on a broad range of linear fatty acids, not seen in other CYP enzymes.
CATALYTIC CARBOXYLATION OF ACTIVATED ALKANES AND/OR OLEFINS
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Page/Page column 65; 66; 67, (2018/02/28)
The present invention relates to a method of reacting starting materials with an activating group, namely alkanes carrying a leaving group and/or olefins, with carbon dioxide under transition metal catalysis to give carboxyl group-containing products. It is a special feature of the method of the present invention that the carboxylation predominantly takes place at a preferred position of the molecule irrespective of the position of the activating group. The carboxylation position is either an aliphatic terminus of the molecule or it is a carbon atom adjacent to a carbon carrying an electron withdrawing group. The course of the reaction can be controlled by appropriately choosing the reaction conditions to yield the desired regioisomer.
H-Bonding-promoted radical addition of simple alcohols to unactivated alkenes
Tian, Yunfei,Liu, Zhong-Quan
supporting information, p. 5230 - 5235 (2017/11/09)
H-Bonding-induced radical addition of simple alcohols to unactivated olefins was achieved. It effectively solved the long-standing problems of reactivity and selectivity in this type of reaction. The hydroxyalkylation occurred via site-specific cleavage of the α-hydroxyl-C-H bond in alcohols. This method allows a highly atom-economical, operationally simple and environmentally benign access to diverse primary, secondary and tertiary alcohols, diols, and even polyfluorinated alcohols. These useful chemicals are traditionally synthesized by using commercially unavailable organometallics via complex operations. In contrast, they can be facilely obtained through this protocol utilizing widely available starting materials.
Hydrogen and trimethylsilyl transfers during EI mass spectral fragmentation of hydroxycarboxylic and oxocarboxylic acid trimethylsilyl derivatives
Rontani, Jean-Franois,Aubert, Claude
, p. 66 - 75 (2015/02/19)
This paper, describing electron ionization mass spectral fragmentation of some hydroxycarboxylic and oxocarboxylic acid trimethylsilyl derivatives, focuses on the formation of fragment ions resulting from the interactions between the two functionalities of these compounds. These interactions result in the formation of fragment ions at [CH2=C(OTMS)2]+·, [CH2=CHC(OTMS)=OTMS]+, [M-31]+, [M-105]+, and [M-RCHO]+· in the case of hydroxycarboxylic acid trimethylsilyl derivatives of formula RCHOTMS(CH2)nCOOTMS and at [RC(OTMS)=CH2]+·, [RC(=OTMS)CH=CH2]+, and [M - RC(=O)CH2]+ in the case of oxocarboxylic acid trimethylsilyl esters of formula RC(=O)(CH2)nCOOTMS. Some of these fragmentations appeared to be sufficiently specific to be used to characterize these compounds. Several fragmentation pathways involving trimethylsilyl and hydrogen transfers were proposed to explain the formation of these different fragment ions and were substantiated by deuterium labeling.
The CYPome of sorangium cellulosum so ce56 and identification of CYP109D1 as a new fatty acid hydroxylase
Khatri, Yogan,Hannemann, Frank,Ewen, Kerstin M.,Pistorius, Dominik,Perlova, Olena,Kagawa, Norio,Brachmann, Alexander O.,Mueller, Rolf,Bernhardt, Rita
experimental part, p. 1295 - 1305 (2011/09/20)
The first systematic study of the complete cytochrome P450 complement (CYPome) of Sorangium cellulosum So ce56, which is a producer of important secondary metabolites and has the largest bacterial genome sequenced to date, is presented. We describe the bioinformatic analysis of the So ce56 cytochrome P450 complement consisting of 21 putative P450 genes. Because fatty acids play a pivotal role during the complex life cycle of myxobacteria, we focused our studies on the characterization of fatty acid hydroxylases. Three novel potential fatty acid hydroxylases (CYP109D1, CYP264A1, and CYP266A1) were used for detailed characterization. One of them, CYP109D1 was able to perform subterminal hydroxylation of saturated fatty acids with the support of two autologous and one heterologous electron transfer system(s). The kinetic parameters for the product hydroxylation were derived.
Facile determination of the absolute stereochemistry of hydroxy fatty acids by GC: application to the analysis of fatty acid oxidation by a P450BM3 mutant
Cryle, Max J.,De Voss, James J.
, p. 547 - 551 (2007/10/03)
The determination of the absolute stereochemistry of hydroxy fatty acid methyl esters as their (S)-ibuprofen esters is possible via standard gas chromatographic techniques. Analyses of various racemic and nonracemic standards and mixtures from enzymic oxi
Catalytic hydroxylation in biphasic systems using CYP102A1 mutants
Maurer, Steffen C.,Kuehnel, Katja,Kaysser, Leonard A.,Eiben, Sabine,Schmid, Rolf D.,Urlacher, Vlada B.
, p. 1090 - 1098 (2007/10/03)
Cytochrome P450 monooxygenases are biocatalysts that hydroxylate or epoxidise a wide range of hydrophobic organic substrates. Their technical application is, however, limited to a small number of whole-cell processes. The use of the isolated P450 enzymes is believed to be impractical due to their low stability, stoichiometric need of the expensive cofactor NAD(P)H and low solubility of most substrates in aqueous media. We investigated the behaviour of an isolated bacterial monooxygenase (mutants of CYP102A1) in a biphasic reaction system supported by cofactor recycling with the NADP +-dependent formate dehydrogenase from Pseudomonas sp 101. Using this experimental set-up cyclohexane, octane and myristic acid were hydroxylated. To reduce the process costs a novel NADH-dependent mutant of CYP102A1 was designed. For recycling of NADH an NAD+-dependent FDH was used. The stability of the monooxygenase mutants under the reaction conditions in the biphasic system was quite high as revealed by total turnover numbers of up to 12,850 in the NADPH-dependent cyclohexane hydroxylation and up to 30,000 in the NADH-dependent myristic acid oxidation.
Regioselectivity and Activity of Cytochrome P450 BM-3 and Mutant F87A in Reactions Driven by Hydrogen Peroxide
Cirino, Patrick C.,Arnold, Frances H.
, p. 932 - 937 (2007/10/03)
Cytochrome P450 BM-3 (EC 1.14.14.1) is a monooxygenase that utilizes NADPH and dioxygen to hydroxylate fatty acids at subterminal positions. The enzyme is also capable of functioning as a peroxygenase in the same reaction, by utilizing hydrogen peroxide i
