Disease relevance of methanoic acid

• The two patients with ocular signs and acidosis had high serum formate concentrations (75 and 55 mg/dL, respectively) [1].
• The special elongation factor SelB of Escherichia coli promotes selenocysteine incorporation into formate dehydrogenases [2].
• The pH-dependent kinetics of this inactivator were consistent with the requirement of an unprotonated carboxyl group in the active site of the enzyme, suggesting that HIV-1 protease is also an aspartic protease [3].
• Furthermore, the coupled electron transport chain from formate to nitrite of Wolinella succinogenes has been reconstituted by incorporating the purified enzymes into liposomes [4].
• Formate dehydrogenase from Methylosinus trichosporium OB3b. Purification and spectroscopic characterization of the cofactors [5].

Psychiatry related information on methanoic acid

• This bi-enzyme sensor has achieved a linear range of 1-300 microM and a detection limit of 1.98 x 10(-7) M for formate (S/N=3), with the response time of 4 min [6].

High impact information on methanoic acid

• Chemical modification of the brain receptor provides evidence for the importance of a carboxyl group that interacts with ligands at the receptor binding site [7].
• In phospholipid bilayers the carboxyl group of HA is localized in the aqueous interface, with an apparent pKa (7.4) similar to other fatty acids; the acyl chain must then penetrate very deeply into the membrane [8].
• The measured apical membrane formic acid permeability is too small to support all of transcellular NaCl absorption in the rat by a mechanism that involves Na/H-Cl/formate transporters operating in parallel with formic acid nonionic diffusion [9].
• The presence of a carboxyl group also appears to alter active ion transport, but this effect cannot be attributed to enhanced diffusion of acid into the tissue [10].
• It is concluded that the presence of a sufficient concentration of an exposed carboxyl group on the mucosal side of the tissue causes an increase in the permeability of the mucosa to acid [10].

Chemical compound and disease context of methanoic acid

• Anaerobically growing Escherichia coli cells contain the enzyme pyruvate formate-lyase which catalyses the non-oxidative cleavage of pyruvate to acetyl-CoA and formate [11].
• The formate-hydrogen lyase complex of Escherichia coli decomposes formic acid to hydrogen and carbon dioxide under anaerobic conditions in the absence of exogenous electron acceptors [12].
• OxlT is the oxalate/formate exchange protein that represents the vectorial component of a proton-motive metabolic cycle in Oxalobacter formigenes [13].
• Using the crystal structure of the homologous FdnI subunit of Escherichia coli formate dehydrogenase-N as a model, the HydC protein was modified to examine residues thought to be involved in menaquinone binding [14].
• The carboxyl group reagents dicyclohexylcarbodiimide (DCCD) and N-ethoxycarboxyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) inactivate the soluble Rhodospirillum rubrum F1-ATPase (RrF1) [15].

Biological context of methanoic acid

• His501 is an additional critical residue at the catalytic site, probably being involved in both the binding of the C-1 carboxyl group of 2-oxoglutarate and the decarboxylation of this cosubstrate [16].
• The deduced amino acid sequence indicates that Nar1 encodes a chloroplast membrane protein with substantial identity to putative formate and nitrite transporters in bacteria [17].
• The 3,570,858 base pair (bp) genome sequence reveals a network of novel c-type cytochromes, connecting multiple periplasmic hydrogenases and formate dehydrogenases, as a key feature of its energy metabolism [18].
• Methylation of unsaturated fatty acids caused a complete loss of inhibitory activity, and subsequent demethylation restored the activity, suggesting that a free carboxyl group was necessary [19].
• However, there was no demonstrable formate oxidation concomitant with phagocytosis in either the presence or absence of exogenous catalase [20].

Anatomical context of methanoic acid

• Chloride/formate exchange with formic acid recycling: a mechanism of active chloride transport across epithelial membranes [21].
• The L-isoaspartyl form of tetragastrin, where the phenylalanine residue is linked to the side-chain carboxyl group of the aspartate residue ([iso-Asp3]tetragastrin), is a substrate for the erythrocyte protein carboxyl methyltransferases, while the normal form is not [22].
• The pathways for transport of Cl- and formate in microvillus membrane vesicles isolated from rabbit renal cortex were evaluated [21].
• Sortase cleaves surface proteins at the LPXTG motif and catalyzes the formation of an amide bond between the carboxyl group of threonine (T) and the amino group of cell-wall crossbridges [23].
• In yeast, mitochondria support cytoplasmic purine synthesis through the generation of formate [24].

Associations of methanoic acid with other chemical compounds

• Clues that connect this interstellar hot core chemistry to the solar system can be found in the cometary detection of methyl formate and the interferometric maps of cometary methanol [25].
• In combination with mutagenesis results, a hydrogen-bonding network from the water molecule adjacent to the iron ligand to the protein surface of the distal pocket through the hydroxyl group of Ser 286 and the carboxyl group of Asp 393 can be assigned to a pathway for proton delivery during the NO reduction reaction [26].
• The interaction of ICAMs with LFA-1 is known to be mediated by a divalent cation bound to the insertion (I)-domain on the alpha chain of LFA-1 and the carboxyl group of a conserved glutamic acid residue on ICAMs [27].
• An in vivo ESR spin-trapping study: free radical generation in rats from formate intoxication--role of the Fenton reaction [28].
• Upon inhibitor binding, the side chains of Tyr-241 and Tyr-300 turn, forming a hydrogen-bonding triad with the carboxyl group of the inhibitor's cysteine moiety, allowing this moiety to fit tightly into the cysteine-binding site with concomitant accommodation of its side chain into a shallow pocket [29].

Gene context of methanoic acid

• The sequence contains three open reading frames of sizes appropriate to encode the three subunits of formate dehydrogenase-N. fdnG contains an in-frame UGA codon that specifies selenocysteine incorporation, and the predicted amino acid sequence of FdnG shows similarity to two other bacterial formate dehydrogenase enzymes [30].
• Taken together these data demonstrate the importance of both Arg269 and Lys220 of RAR-beta for the binding of RA, possibly by interacting with the negatively charged carboxyl group of RA [31].
• We conclude that mouse Slc26a6 has affinity for oxalate, sulfate, and HCO(3)(-) in addition to Cl(-) and formate and can function in multiple exchange modes involving pairs of these anions [32].
• GRIP1 PDZ7 contains a closed carboxyl group-binding pocket and a narrow alphaB/betaB-groove that is not likely to bind to classical PDZ ligands [33].
• Moreover, it could be shown that there was a corresponding reduction of approximately 50% in the amount of formate excreted by a focA mutant into the culture medium [34].

Analytical, diagnostic and therapeutic context of methanoic acid

• As measured by miniature glass pH microelectrodes, this lack of formate effect on JV was related to a less extensive acidification of the tubule fluid when high HCO-3 solutions were used as perfusate [35].
• Several apparent microscopic ionization constants have been determined from the carboxyl group NMR titration curves, and possible assignments are discussed [36].
• Sequence analyses of tryptic, V8 protease-, and Asp-N protease-generated peptides show that the heme propionyl carboxyl group at the surface of the cytochrome forms an ester bond with Ser162 of the reductase, thus implicating Lys163 as the normal participant in ionic bonding between the active sites of the two proteins [37].
• Noting that nisin has Ile at position 4, site-directed mutagenesis was used to change Glu4 of subtilin to Ile, in order to eliminate this carboxyl-group participation [38].
• The transport characteristics of aminocephalosporin antibiotics, possessing an alpha-amino group and a carboxyl group, in brush-border membranes isolated from rabbit small intestine have been studied by a rapid filtration technique [39].

References