Disease relevance of carbon dioxide

• Whereas the central core of dermaseptin (residues 10-19) was virtually inactive, alteration of the COOH-terminal carboxylic group of dermaseptin-(1-18) to a carboxamide yielded a peptide exhibiting enhanced antimicrobial potency, yet displaying even less in vitro toxicity compared with dermaseptin [1].
• In contrast, the E. coli enzyme was a nonselective enzyme that accommodated substrates without specifically recognizing the C-terminal carboxy group of the Cys-Gly moiety of gamma-glutamyl compounds or the acceptor molecules [2].
• Penicillin acylase (PA) from Kluyvera citrophila was inhibited by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ), a specific carboxy-group-reactive reagent [3].
• Antiamoebic and toxicity studies of a carbamic acid derivative and its therapeutic effect in a hamster model of hepatic amoebiasis [4].
• The mechanism through which the C-17(3) carboxy group of bacteriochlorophyllide a is esterified to produce bacteriochlorophyll aphytyl of Rhodopseudomonas spheroides and bacteriochlorophyll ageranylgeranyl of Rhodospirillum rubrum was studied by using 5-aminolaevulinate labelled with 18O at its C-1 carboxy oxygen atoms [5].

High impact information on carbon dioxide

• The nonamidated carboxylic group at the C terminus was proven by synthesis of amidated and nonamidated hGal and by mass spectrometry after selective methylation of all free carboxylic groups [6].
• The data are compatible with a model in which the conductive path of the channel contains a functional arginine, possibly forming a salt bridge with a carboxylic group, which is involved in Na+ translocation and amiloride binding [7].
• In N protein, as well as in oxidized insulin B chain and glucagon, Lon protease preferentially cut at bonds at which the carboxy group was contributed by an amino acid with an aliphatic side chain (leucine or alanine) [8].
• Introduction of a methyl ester or decarboxylation of the C-terminal carboxy group was achieved with an intein-based protein expression system and an elongation rate assay was developed to test the effects of the modifications [9].
• The C-terminal carboxy group of T7 RNA polymerase ensures efficient magnesium ion-dependent catalysis [9].

Chemical compound and disease context of carbon dioxide

• The carbamic acid, N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) is a substrate for the E. coli PurE (Mueller et al., 1994) but not for the G. gallus AIR carboxylase [10].
• For reducing the gastrointestinal toxicity associated with ibuprofen its carboxylic group was condensed with the hydroxyl group of 1,2,3-trihydroxy propane 1,3-dipalmitate/stearate to give the ester prodrugs 3a and 3b [11].
• Also, carbamic acid products of several amines, such as beta-N-methylamino-L-alanine (BMAA), ethylenediamine, and L-cysteine have been implicated in toxicity [12].

Biological context of carbon dioxide

• Modification with 1-(3-dimethylaminopropyl)-3-ethylcarbodi-imide (EDAC) confirmed this view, and analysis of the order of reaction and inactivation kinetics suggested the presence of a single carboxy group at a catalytic centre of the active site [13].
• Enzyme-catalysed exchange of label into the terminal carboxy group was found to occur in some cases without hydrolysis of a peptide bond [14].
• This is concluded to arise from inadvertent methyl esterification of the C-terminal carboxy group [15].
• Using a combination of solid-phase and solution methods, we synthesized a series of cyclic [Leu5]enkephalin analogues by substitution of D-alpha, omega-diamino acids in position 2 of the enkephalin sequence and cyclization of the omega-amino group to the C-terminal carboxy group of leucine [16].
• The structure-activity relationships indicated that both a free thiol and free amino group were required for peroxidase-oxidase activity, and also that a free carboxy group abolished activity [17].

Anatomical context of carbon dioxide

• The physiological role of protein carboxy-group methylation reactions in human erythrocytes was studied with calmodulin as an endogenous methyl-group acceptor [18].
• Cross-linking of the rigor complex between filamentous actin and skeletal-muscle myosin subfragment 1 was accomplished by the carboxy-group-directed zero-length protein cross-linker, 1-ethyl-3-[3-(dimethylamino)propyl]carbodi-imide [19].
• The chemically related compound carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]et hyl ]-, 2-benzofuranylmethyl ester, [R-(R*,S*)] (CI-1021) is also a selective NK1 receptor antagonist but can penetrate into the central nervous system [20].
• The purpose of this study was to evaluate the effects of the new anticonvulsant drug N-(2-amino-4-[fluorobenzylaminol-phenyl) carbamic acid ethyl ester (retigabine, D-23129, ASTA Medica, Dresden, Germany) on different patterns of epileptiform activity induced by 4-aminopyridine (4AP) in rat entorhinal cortex hippocampal slices [21].
• The phase preferences of egg yolk phosphatidylcholine (EYPC) have been examined in the presence of tertiary amine anesthetics [2-(propyloxy)phenyl]-2-(1-piperidinyl)ethyl ester of carbamic acid (C3A) and [2-(heptyloxy)phenyl]-2-(1-piperidinyl)ethyl ester of carbamic acid (C7A, heptacaine) [22].

Associations of carbon dioxide with other chemical compounds

• 1. It is concluded that the active cysteine beta-lactamase has four functional groups at the active site, one nucleophilic thiolate of Cys-70, one neutral acid (most probably the carboxy group of Glu-166, from the crystal structures) and two cationic residues (most probably Lys-73 and Lys-234) [23].
• The pH-dependence of 4'-methylumbelliferyl beta-cellotrioside hydrolysis indicates the presence of a protonated group with a pK 5.5 in the reaction mechanism, and the possible involvement of a carboxy group is corroborated by a temperature study (delta Hion = -15.9 J/mol) [24].
• We demonstrate that compounds that have two hydroxyl groups para and ortho to the carboxylic group and a carboxylic group at a distance of two carbons from the phenol ring inhibit heparanase activity and SMC proliferation, as well as induced an almost complete release of bFGF from ECM [25].
• The new L-amino acid analogues bearing an additional nitro, amino, hydroxy, methoxy or carboxy group at the 3'-position of the phenol ring of tyrosine were prepared in an orthogonally protected form suitable for solid-phase peptide synthesis using Fmoc protocols [26].
• Thus, in the human enzyme, a specific residue in the Cys-Gly binding site played a critical role in recognizing the Cys-Gly moiety or the acceptor molecules by interacting with the C-terminal carboxy group, whereas the Cys side chain and the Cys-Gly amide bond were not recognized significantly [2].

Gene context of carbon dioxide

• We found that this additional carboxylic group on glutamate prevents its interaction with group-I mGlu receptors and generates a potent group-II antagonist (K(B) = 55 microM on mGlu2) [27].
• In the reverse orientation, which is the major binding mode of T4Ac, the ligand is bound deep in the TTR channel, with the carboxylic group bound in the P3' pocket and forming simultaneous polar interactions with the residues constituting the two hormone-binding sites [28].
• The structural requirements to the PAT2 substrates - when considering both low and high affinity type substrates - are similar to those reported for the PAT1 protein with the essential features of a free carboxy group and a small side chain [29].
• These results demonstrate that the addition of a third carboxylic group to ACPD can change its activity (from agonist to antagonist) and either increase or decrease its selectivity and/or affinity for the various mGluR subtypes [30].
• Tandem mass spectrometric data-FAAH inhibitory activity relationships of some carbamic acid O-aryl esters [31].

Analytical, diagnostic and therapeutic context of carbon dioxide

• Oligonucleotide-directed mutagenesis of cloned Bacillus cereus 5/B/6 beta-lactamase II was used in an 'in vivo' study to investigate the role of carboxy-group-containing amino acids near the active site of the enzyme [32].
• These compounds, characterized by an N-alkyl carbamic acid O-aryl ester structure, exert potent anxiolytic-like effects in animal models [31].
• Immobilization of the enzyme to the released carboxy group after acid hydrolysis was performed using dicyclohexylcarbodiimide [33].
• A standard acidic titrant, and an automatic titrator operating in an equilibrium titration mode were used to characterize and quantify the carboxy group content of Sepia melanins and several other commonly used melanins purified by a standard method (Zeise et al., Pigment Cell Res. [Suppl] 2:48-53, 1992) [34].
• FTIR spectroscopic analysis provides evidence for interactions between NaIMC and IMC through a combination of hydrogen bonding and ion-dipole interactions between the carboxylic group of the acid and the carboxylate anion of the salt [35].

References