Oxalic Acid

Riemenschneider, Wilhelm; Tanifuji, Minoru

doi:10.1002/14356007.a18_247

Cited by 14 publications

(11 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oxalate is competitive with respect to oxaloacetate and has a dissociation constant of 8.9 μM for the metal center of chicken liver PC [18]. At neutrality, the two carboxylates of oxalate are deprotonated (pK a1 = 1.19; pK a2 =4.22) [19]. In this ionization state, oxalate is a strong chelator of metal ions and shares structural and chemical properties with the enolpyruvate intermediate.…”

Section: Resultsmentioning

confidence: 99%

Insights into the carboxyltransferase reaction of pyruvate carboxylase from the structures of bound product and intermediate analogs

Lietzan

Maurice

2013

Biochemical and Biophysical Research Communications

View full text Add to dashboard Cite

Pyruvate carboxylase (PC) is a biotin-dependent enzyme that catalyzes the MgATP- and bicarbonate-dependent carboxylation of pyruvate to oxaloacetate, an important anaplerotic reaction in central metabolism. The carboxyltransferase (CT) domain of PC catalyzes the transfer of a carboxyl group from carboxybiotin to the accepting substrate, pyruvate. It has been hypothesized that the reactive enolpyruvate intermediate is stabilized through a bidentate interaction with the metal ion in the CT domain active site. Whereas bidentate ligands are commonly observed in enzymes catalyzing reactions proceeding through an enolpyruvate intermediate, no bidentate interaction has yet been observed in the CT domain of PC. Here, we report three X-ray crystal structures of the Rhizobium etli PC CT domain with the bound inhibitors oxalate, 3-hydroxypyruvate, and 3-bromopyruvate. Oxalate, a stereoelectronic mimic of the enolpyruvate intermediate, does not interact directly with the metal ion. Instead, oxalate is buried in a pocket formed by several positively charged amino acid residues and the metal ion. Furthermore, both 3-hydroxypyruvate and 3-bromopyruvate, analogs of the reaction product oxaloacetate, bind in an identical manner to oxalate suggesting that the substrate maintains its orientation in the active site throughout catalysis. Together, these structures indicate that the substrates, products and intermediates in the PC-catalyzed reaction are not oriented in the active site as previously assumed. The absence of a bidentate interaction with the active site metal appears to be a unique mechanistic feature among the small group of biotin-dependent enzymes that act on α-keto acid substrates.

show abstract

Section: Resultsmentioning

confidence: 99%

Insights into the carboxyltransferase reaction of pyruvate carboxylase from the structures of bound product and intermediate analogs

Lietzan

Maurice

2013

Biochemical and Biophysical Research Communications

View full text Add to dashboard Cite

show abstract

“…These were (i) 0.5% povidone iodine (PI) [28], (ii) 1% povidone iodine (PI), (iii) 1% cetylpyridinium chloride/2% sodium chloride (iv) 2% cetyl-pyridinium chloride/4% sodium chloride, (v) 5% oxalic acid (vi) 10% oxalic acid [29] (vii) 0.5% virkon and (viii) 1% virkon (ix) 20% benzalkonium chloride and (x) benzalkonium chloride at 40% [30, 31]. Therefore, two dilutions each of the 5 chemical agents were prepared and used.…”

Section: Methodsmentioning

confidence: 99%

Evaluating decontamination protocols for the isolation of Mycobacterium ulcerans from swabs

et al. 2017

View full text Add to dashboard Cite

Background Mycobacterium ulcerans (M. ulcerans) is the causative agent of Buruli Ulcer (BU) disease. In order to inhibit the growth of the microbial contaminants during culture of M. ulcerans, it is necessary to decontaminate BU samples with effective chemical agents. This study aimed at investigating some selected chemicals as potential decontamination agents for the isolation of M. ulcerans from swabs.ResultsPovidone iodine at 0.5 and 1% exhibited the lowest contamination and recovery rate for microbial contaminants and M. ulcerans. The most effective decontamination method was the protocol using 2% cetylpyridinium chloride/4% sodium chloride (recovery rate = 53%, contamination rate = 14%). The observed difference between the recovery rate of 2% CPC/4% NaC and the other protocols was however not statistically significant (p = 0.76).ConclusionsTwo percent (2%) cetylpyridinium chloride/4% sodium chloride can be conveniently used as an alternative decontamination method for the isolation of M. ulcerans from swabs.

show abstract

“…Under relatively acidic conditions, ascorbic acid is used widely as electron donor (p K a s 4 and 11.3), it has the ability to act also as proton donor, providing H + to be reduced to H 2 . Carboxylic acids, such as lactic acid (p K a 3.9) and oxalic acid (p K a 1.2 and 4.2), also have been used in aqueous solutions over a wide pH range from slightly acid to slightly basic . Therefore, working at a pH value close to the p K a of the electron donor enhances the H 2 production rate.…”

Section: Influence Of System Units On Photocatalytic Performancementioning

confidence: 99%

Comprehensive review and future perspectives on the photocatalytic hydrogen production

Corredor

Rivero

Rangel

et al. 2019

J of Chemical Tech & Biotech

174

View full text Add to dashboard Cite

Hydrogen represents a renewable energy alternative that may positively contribute to get over the global energy crisis while at the same time reducing its environmental burden. Overcoming the challenge of reaching this potential could be helped by careful choice of hydrogen (H2) sources. Photocatalytic generation of H2, although a minor alternative, appears to be a very good option at the time that liquid wastes are being degraded; therefore, this approach has given rise to an increasing number of interesting studies. Here, we aim to provide an integrated overview of the different photocatalytic, heterogeneous, homogeneous and hybrid systems. First, we categorize the units and mechanisms that take part in the photocatalytic process, and secondly we analyze their role and draw comparative conclusions. Thus, we analyze the role of (i) the electron source to carry out proton reduction, (ii) the proton source, which can be free protons in the medium or a proton donor compound, (iii) the catalyst nature and concentration, and (iv) the photosensitizer nature and concentration. We also provide an analysis of the influence of the solvent, especially in homogenous systems as well as the influence of pH. We provide a comparison of the photocatalytic performance, highlighting the advantages and disadvantages, of different systems. Thus, this review is, on the one hand, an update on the state of the art of photocatalytic generation of H2 from a full perspective that integrates homogeneous, heterogeneous and hybrid systems, and, on the other, a source of useful information for future research. © 2019 Society of Chemical Industry

show abstract

Oxalic Acid

Cited by 14 publications

References 18 publications

Insights into the carboxyltransferase reaction of pyruvate carboxylase from the structures of bound product and intermediate analogs

Insights into the carboxyltransferase reaction of pyruvate carboxylase from the structures of bound product and intermediate analogs

Evaluating decontamination protocols for the isolation of Mycobacterium ulcerans from swabs

Comprehensive review and future perspectives on the photocatalytic hydrogen production

Contact Info

Product

Resources

About