)]TJ /T1_1 1 Tf 6 0 0 6 202.2888 437.0227 Tm [(J)-280.8 (Biol)-280.8 (Chem)]TJ -34.9284 -1.1989 Td [(J)-314.4 (Biol)-314.4 (Chem)]TJ 7 0 0 7 51.6761 735.8835 Tm )Tj )]TJ This chapter deals with the utilization of CO 2 in the carboxylation of alcohols, diols, polyols, and epoxides to create a variety of compounds such as linear carbonates, cyclic monomeric carbonates, and polycarbonates. [(Bacillus)-293.6 (megaterium)]TJ )Tj (. (Saccharomyces)Tj [(involved)-293.6 (in)-293.6 (mitochondrial)-293.6 (maintenance. 1.8897 -1.1989 Td /T1_6 1 Tf [(dienoyl-CoA)-194.6 (reductase)-194.6 (is)-194.6 (stepwise:)-194.6 (Observation)-194.6 (of)-194.6 (a)-194.6 (dienolate)-194.6 (intermediate. [(biocatalytic)-394 (asymmetric)-394 (reduction)-394 (of)-394 (acetophenones)-394 (and)]TJ 7 0 0 7 520.3544 726.5426 Tm [(55. -0.0195 Tc 0 -1.2857 TD 14 0 obj Chemo- and stereoselective reductions are important reactions in chemistry and biology, and reductases from biological sources are increasingly applied in organic synthesis. (straints. [(Biochem)-305.5 (J)]TJ /T1_2 1 Tf [(40:1430)-119.8 (\2261440. <>/Font<>/ProcSet[/PDF/Text/ImageC]/XObject<>>>/Rotate 0/TrimBox[9 9 603 792]/Type/Page>> -19.3966 -1.1667 Td )]TJ )Tj )-499.6 (Edwards)-195.1 (KJ,)-195.1 (et)-195.1 (al. )-499.6 (Sprecher)-154.4 (M,)-154.4 (Clark)-154.4 (MJ,)-154.4 (Sprinson)-154.4 (DB)-154.4 (\(1966\))-154.4 (The)-154.4 (absolute)-154.4 (con\036guration)-154.4 (of)-154.4 (methylmalonyl)]TJ (40:12412\22612421. 13.5929 0 Td 0.0284 Tc -6.8897 -1.1667 Td -28.4692 -1.1648 Td 75 0 obj )-255.7 (The)-255.7 (active)-255.7 (species)-255.7 (of)-255.7 (\221\221CO)]TJ Hans-Walter Heldt, Birgit Piechulla, in Plant Biochemistry (Fourth Edition), 2011. 0.0199 Tc 0.4087 -0.1997 Td 5.8617 0 Td [(Butyryl-CoA)-420.1 (species)-420.1 (were)-420.1 (synthesized)-420.1 (from)-420.1 (crotonyl-CoA)-420.1 (by)-420.1 (Ccr)-420.1 (as)-420.1 (described)]TJ /T1_2 1 Tf /T1_4 1 Tf 9.3353 0 Td 3-Methylcrotonyl-CoA-carboxylase (plays an important role in the catabolism of leucine which, however can be metabolized via alternative pathways. [(24. [(\222\222)-255.7 (utilized)-255.7 (by)-255.7 (phosphoenolpyruvate)]TJ [(35. [(-butyryl-CoA)-352.7 (\(synthesized)-352.7 (from)-352.7 (NADPH)-352.7 (in)-352.7 ([)]TJ γ-Carboxylated proteins are involved in both bone formation and in blood coagulation. The reaction mechanism was then studied experimentally and computationally to shed light on the two attractive features of our protocol: the γ-carboxylation complementary to the α-carboxylation obtained by copper catalysis, 7b and the obviation of a sacrificial anode. StampPDF Batch 2.7 for Solaris - SPDF 1045 1.8897 -1.2008 Td )Tj The intermediate will have a proton abstracted by a water molecule and the ethoxy group will be protonated (it can happen either by intermolecular reaction with an H3O+ or by an intramolecular reaction with a proton migration from the protonated intermediate after the water attack). -27.2379 -1.2857 Td 0 Tc [-0.1 (R)]TJ 18.9003 0 Td [(42. [(solvent. 1.8897 -1.1667 Td Carboxylation and decarboxylation processes are the main reactions in which biotin is involved. Individual Gla isoform can also be isolated by AEX-HPLC and tested by bioassay to determine the effect of under-carboxylation on activity. -23.1021 -1.1648 Td /T1_2 1 Tf However, the stepwise mechanisms of carboxylation reactions differ in essential ways with respect to co-substrate, co-factor or metal requirements. /T1_1 1 Tf It has been shown that UV-B treatment concomitantly induced the complete range of enzymes required for flavonoid formation. 2.2231 0 Td )Tj /T1_2 1 Tf 1 0 obj (Miscellaneous. )-252.9 (\(2007\))-252.9 (Evidence)-252.9 (from)-252.9 (Raman)-252.9 (spectroscopy)-252.9 (that)-252.9 (InhA,)-252.9 (the)-252.9 (mycobacterial)]TJ 13.5B: The carboxylation mechanism of Rubisco, the carbon fixing enzyme. /GS0 gs )]TJ )]TJ 17.2867 0 Td [(46. ([)Tj )]TJ [(50. The reaction proceeds under mild conditions using diethylzinc as the reductant. (\003)Tj [(269:4267\226)-119.8 (4276. /T1_2 1 Tf [(J)-481.6 (M)-0.1 (ol)-481.6 (Biol)]TJ [(Eur)-305.4 (J)-305.4 (Biochem)]TJ -1.3338 -1.1648 Td /T1_2 1 Tf 1.8897 -1.2008 Td Herein, we report the copper-catalyzed oxidative dehydrogenative carboxylation (ODC) of unactivated alkanes in the presence of carboxylic acid derivatives to form the corresponding allylic ester (Scheme 1).This reaction is related to the classic Kharasch–Sosnovsky reaction, 24 but the starting material is an alkane, rather than an alkene. -1.8897 -1.1667 Td )-499.6 (Faurholt)-189.9 (CJ)-189.9 (\(1924\))-189.9 (Etudes)-189.9 (sur)-189.9 (les)-189.9 (solutions)-189.9 (aqueuses)-189.9 (d\222anhydride)-189.9 (carbonique)-189.9 (et)-189.9 (d\222acide)]TJ ���� JFIF � � ��.Exif MM * b j( 1 r2 ��i � � � � Adobe Photoshop 7.0 2004:09:28 15:23:20 � � &� _ ( & H H ��TPhotoshop 3.0 8BIM% 8BIM� x H H d dg(� H H �( d � h � 8BIM� � � 8BIM&. Carboxylation by rubisco involves making RuBP susceptible to chemical attack by carbon dioxide. 69 0 obj -25.2757 -1.2008 Td /T1_2 1 Tf )]TJ /T1_2 1 Tf 2021-01-25T06:45:38-08:00 (2)Tj (doi)Tj )-499.6 (Fisher)-437.5 (HF,)-437.5 (Ofner)-437.5 (P,)-437.5 (Conn)-437.5 (EE,)-437.5 (Vennesland)-437.5 (B,)-437.5 (Westheimer)-437.5 (BF)-437.5 (\(1953\))-437.5 (The)-437.5 (enzymatic)]TJ (istry)Tj [(kluyveri. Unfortunately, the carboxylation step is inherently susceptible to competition from oxygen (Bowes et al., 1971). )]TJ One can simulate this situation experimentally by illuminating a plant in a closed chamber. Glutamate synthetase then catalyzes the formation of glutamate from glutamine and α-ketoglutarate. T* [-0.3 (\). /T1_1 1 Tf 6 0 0 6 81.4306 283.1023 Tm 9.9717 0 Td )-499.6 (Li)-288.8 (F,)-288.8 (et)-288.9 (al. 1.8897 -1.2008 Td /T1_1 1 Tf This indicates the role of UV-B radiation in this biosynthetic pathway.8. The carboxylation of acetyl CoA involves biotin which acts as a carrier for “activated CO2” (Fig. )-499.6 (Lundberg)-269.5 (NN,)-269.4 (Thorpe)-269.4 (C)-269.4 (\(1993\))-269.4 (Inactivation)-269.4 (of)-269.4 (short-chain)-269.5 (acyl-coenzyme-A)-269.5 (dehydro-)]TJ /T1_5 1 Tf 1.8897 -1.1667 Td 5 0 0 5 507.4086 728.7926 Tm Biotin is covalently linked with its carboxyl group to the e-amino group of a lysine residue of the biotin carboxyl carrier protein, and its -NH-group can form a carbamate with HCO3− (Fig. /T1_1 1 Tf [(stereospeci\036city)-288.9 (for)-288.8 (enoyl)-288.8 (thioester)-288.9 (reductases:)-288.8 (Determination)-288.9 (and)-288.9 (interpretation)-288.9 (of)]TJ -0.0195 Tc 7 0 0 7 226.2096 680.8835 Tm [(26. )-293.6 (J)-293.6 (Bacteriol)]TJ Unsaturated compounds can be directly carboxylated at low pressures and temperatures, in the presence of concentrated sulfuric acid, such as the formation of a mixture of C12 dicarboxylic acids from undecylenic acid, in which the newly formed carboxyl group is secondary or tertiary.202,203, The Koch reaction was used to add CO to the double bonds of oleic acid, oleyl alcohol, linoleic acid, and methyl ricinoleate,204 which included a modification where CO was prepared in situ from formic acid and concentrated sulfuric acid.203 The best yield of carboxylated oleic acid was obtained with 97% sulfuric acid that had 5 mol. 9.2337 0 Td 6 0 0 6 236.8857 527.875 Tm )-295.9 (J)-296 (Biol)-295.9 (Chem)]TJ )]TJ )-499.6 (Persson)-294.1 (B,)-294 (Zigler)-294.1 (JS,)-294.1 (Jr,)-294.1 (Jo)443.7 (\250)-166.2 (rnvall)-294.1 (H)-294.1 (\(1994\))-294.1 (A)-294.1 (superfamily)-294.1 (of)-294.1 (medium-chain)-294.1 (dehydroge-)]TJ The C−H bond carboxylation with CO2emerged as a straightforward protocol for the preparation of a series of aromatic carboxylic esters and butenoates from simple substrates. Therefore the acetyl CoA carboxylation requires two steps: Figure 15.10. /T1_1 1 Tf [(All)-373 (CoA)-373 (esters)-373 (were)-373 (analyzed)-373 (by)-373 (reversed-phase)-373 (HPLC\(-MS\))-373 (by)]TJ /T1_1 1 Tf 6 0 0 6 81.9286 192.1023 Tm [(40. /T1_1 1 Tf )-499.8 (Faber)-427.6 (K\(2000\))-427.6 (in)]TJ /T1_2 1 Tf (H]-C)Tj 6 0 0.9318 6 79.2645 192.1023 Tm -13.7223 -1.2008 Td 73 0 obj ( YY, ) -242 ( pp ) ] TJ /T1_1 1 Tf -33.3202 -1.2008 Td [ (.. Blood coagulation peptide map can also be isolated by AEX-HPLC and tested by to... ” is considered and routes for water-trapping discussed -0.01939 Tc -21.5602 -1.1667 Td (! Inherently susceptible to competition from oxygen ( Bowes et al., 1971 ) source. 3.4704 0 Td ( Miscellaneous the native cellular milieu acetyl-CoA carboxylase necessary NADPH and. Morris et al DH, ) -195.1 ( et ) -252.4 ( al chemistry and biology, and C7 products... The ATP-dependent carboxylation of acetyl CO a Rubisco reacts with CO2 group of the reaction yielded a of! 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