Trans-Aconitate

Aliphatic acids Formic, acetic, butyric, popionic, malic, citric, isocitric, oxalic, fumaric, malonic, succinic, maleic, tartaric, oxaloacetic, pyruvic, oxoglutaric, maleic, glycolic, shikimic, cis-aconitic, trans-aconitic, valeric, gluconic... 

Figure 3 Gradient separation of anions using suppressed conductivity detection. Column 0.4 x 15 cm AS5A, 5 p latex-coated resin (Dionex). Eluent 750 pM NaOH, 0-5 min., then to 85 mM NaOH in 30 min. Flow 1 ml/min. 1 fluoride, 2 a-hydrox-ybutyrate, 3 acetate, 4 glycolate, 5 butyrate, 6 gluconate, 7 a-hydroxyvalerate, 8 formate, 9 valerate, 10 pyruvate, 11 monochloroacetate, 12 bromate, 13 chloride, 14 galacturonate, 15 nitrite, 16 glucuronate, 17 dichloroacetate, 18 trifluoroacetate, 19 phosphite, 20 selenite, 21 bromide, 22 nitrate, 23 sulfate, 24 oxalate, 25 selenate, 26 a-ketoglutarate, 27 fumarate, 28 phthalate, 29 oxalacetate, 30 phosphate, 31 arsenate, 32 chromate, 33 citrate, 34 isocitrate, 35 ds-aconitate, 36 trans-aconitate. (Reproduced with permission of Elsevier Science from Rocklin, R. D., Pohl, C. A., and Schibler, J. A., /. Chromatogr., 411, 107, 1987.)...

Exudation occurs in response to environmental constraints, especially P deficiency (e.g., Jones 1998 Hinsinger et al. 2003) and differs depending on the P-form (Lambers et al. 2002) and plant species (Nuruzzaman et al. 2006). Banksia grandis exuded citrate, malate, and trans-aconitate when supplied with aluminium-phosphate. It exuded less of these tricarboxylates and dicarboxylates, but instead lactate and acetate, when supplied with iron-phosphate (Lambers et al. 2002). Plant species differ in their abilities to use various P species (van Ray and van Diest 1979), which can be due to differences in their exudation behavior (Nuruzzaman et al. 2006) and acidification of the root zone (Haynes 1992). This can influence the interspecific competition and coexistence of species, as we will discuss later. 

Koh, H. S., M. Kim, T. Obata, H. Fukami, and S. Ishii. Antifeedant in barnyard grass against the brown planthopper-trans-aconitic acid. Rice Brown Planthopper (Pap Semin) 1976 Food Fert Technol Center Asian Pac Reg, Taipei, Taiwan. 

Krogh, A. 1971. The content of trans-aconitic acid in Asarum europaeum L. determined by means of a chromatogram spectrophotometer. Acta Chem. Scand. 25 1495-1496. 

Human urine Cardiovascular risk 4680 1H NMR Isoleucine Valine Methylguanidine Hippurate 2-Hydroxibutirate Succine Scyllo-inositol Trans-aconitate Proline betaine (21)... 

Bromate, chloride, bromide, nitrite, nitrate, hypophosphite (HP022 ), selenite, selenate, sulphate, phosphate, pyrophosphate, arsenate, chromate, a-hydroxybutyrate, butyrate, formate, acetate, glycolate, gluconate, valerate, a-hydroxy valerate, pyruvate, monochloroacetate, dichloroacetate, trifluoroacetate, galactonurate, gluconurate, a-keto-glutarate, oxalate, fumarate, phthalate, oxalacetate, citrate, isocitrate, cis aconitate, trans aconitate, succinate, maleate, malonate, quinate, tartrate, hexane sulphonate, octane sulphonate, octane sulphate, decane sulphonate, dodecane sulphonate and dodecane sulphate... 

Lauble, H., Kennedy, M.C., Beinert, H., Stout, C.D. (1994). Crystal structures of aconitase with trans-aconitate and nitro-citrate bound. J. Mol. Biol. 237 437-51. 

Enzymatic isomerization of c/s-aconitate to trans-aconitate apparently also involves proton abstraction, with resonance in the anion extending into the carboxylic acid group. Its mechanism may be directly related to that of the oxosteroid isomerase. However, there are other 1,3-proton shifts in which neither a carbonyl nor a carboxyl group is present in the substrate (Eqs. 13-55,13-56). 

In contrast, GLH eggs tolerated trans-aconitic acid levels which were lethal to BPH eggs. In nature, GLH thrives on barnyard grass. 

Figure 7. Effect of trans-aconitic acid, a barnyard grass chemical, on hatching of eggs of three biotypes of N. lugens.

Formic, acetic, oxalic, pyruvic, L-malic, succinic, fumaric, tartaric, citric, trans-aconitic, gluconic, a-ketoglutaric, glutaric acid 14 different aromatic acids... 

MaUc, succinic, citric, trans-aconitic acid C1-C4 mono-carboxylic, lactic, pyruvic, citric, fumaric, malic, succinic,... 

Long chain hydrocarbons and fatty acids are best known as constitutents of waxes and lipophilic compounds. Some representatives of this natural product group show high antiprotozoal activity but mostly combined with a high levels of toxicity to mammalian cells. One example is traws-aconitic acid (2) that was used in combination with sodium stibogluconate, allopurinol, or pentamidine for experimental visceral leishmaniasis to determine synergistic effects [34]. When these three drugs (50, 15, 8 mM/kg/day, respectively) were used with trans-aconitic acid (5 mM/kg/day) the parasite load in BALB/c mice was inhibited by 100, 88, and 100%, respectively. At tested concentration trans-aconitic acid itself showed an inhibition of 59.2 %. 

A further synthesis of labeled aspartic acids 2Ia used the enzyme aconitate isomerase (EC 5.3.3.7). This enzyme interconverts cis- and frans-aconitates 238 and 239, respectively, with exchange of the 4-pro-S hydrogen. The (4S)-[4- Hi]-trans-aconitate 239, H = H, produced in H20 could be ozonized and then converted in situ with sodium periodate and glutamic oxaloacetic transaminase (EC 2.6.1.2) to (3S)-[3- H,]aspartic acid 21a, (223). This process involves (3S)-[3- Hi]oxaloacetic acid 240, Ha = H, as an intermediate. 

Figure 4.17. Separation of a mixture of inorganic and organic anions by gradient elution ion chromatography with conductivity detection using a micromembrane suppressor. A variable rate gradient from 0.5 mM to about 40 mM sodium hydroxide on an lonPac ASH column was used for the separation. Peak identification 1 = isopropylmethylphosphonate 2 = quinate 3 = fluoride 4 = acetate 5 = propionate 6 = formate 7 = methylsulfonate 8 = pyruvate 9 = chlorite 10 = valerate 11 - monochloroacetate 12 - bromate 13 = chloride 14 = nitrite 15 = trifluoroacetate 16 = bromide 17 = nitrate 18 = chlorate 19 = selenite 20 = carbonate 21 = malonate 22 = maleate 23 = sulfate 24 = oxalate 25 = ketomalonate 26 = tungstate 27 = phthalate 28 = phosphate 29 = chromate 30 = citrate 31 = tricarballylate 32 = isocitrate 33 = cis-aconitate and 34 = trans-aconitate. Each ion is at a concentration between 1 to 10 mg/1. (From ref. [417]. Marcel Dekker).

Figure 5 Structures of the (a) Fe3S4(Cys)4 ferredoxin site (PDB 7FD1) (b) aconitase active site with bound trans-aconitate (PDB lACO) (c) NiFe4Ss cluster in carbon monoxide dehydrogenase (PDB IJQK).

CsH OJ- COOH H2c4 COOH °Co-y-irr. of trans-aconitic acid/ Neat EPR/ 300 H(l, 1, 3) 1.4 66Chal... 

Fig. 14.4 Separation of organic acids (as anions) and inorganic anions in wine. (Reproduced by permission of Dionex.) Conditions column, 25cm x4mm i.d. and precolumn stationary phase, lonPac AS11-HC mobile phase, 1.5 ml min non-linear gradient from 1 mM to 60 mM NaOH and from 0 to 20% methanol temperature, 30°C conductivity detector after packed suppressor. Peaks 1 = lactate 2 = acetate 3 = formate 4 = pyruvate 5 = galacturonate 6 = chloride 7 = nitrate 8= succinate 9 = malate 10 = tartrate 11 =fumarate 12 = sulphate 13 = oxalate 14 = phosphate 15 = citrate 16 = isocitrate 17 = c/s-aconitate 18= trans-aconitate.

---