Methanol Production via Bioelectrocatalytic Reduction of Carbon Dioxide: Role of Carbonic Anhydrase in Improving Electrode Performance

The effect of carbon dioxide on oxygen tension in the endolymph was determined by the micropolarographic technique. Different concentrations (5% and 10% CO2) and different exposure times (3, 5, and 20 minutes) were investigated. The highest levels of Po2 in the endolymph (101.7, 93.9 and 69.5 mm Hg) were accomplished by respiration of 10% CO2, 90% O2, for 20, 5, and 3 minutes consecutively. The lowest Po2 increase, 50.7 mm Hg was observed after breathing 5% CO2, 90% O2 for 20 minutes. Extreme hypercapnia caused an increase of endocochlear potentials (EP) in all groups. In the second group EP increased from +79.3 to +84.9 and in all groups they had returned to the pretreatment level after CO2 discontinuation. These results support the theory that carbonic anhydrase participates in the generation of EP. At the same time that EP increased, cochlear microphonics declined and opposite after the breathing mixture was discontinued. The results permit the conclusion that high levels of Po2 in endolymph is achievable even with short periods of respiration with high CO2 mixture, and suggest the role of carbonic anhydrase during EP generation.

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Fixation of atmospheric carbon dioxide by a series of hydroxo complexes of divalent metal ions and the implication for the catalytic role of metal ion in carbonic anhydrase. Synthesis, characterization, and molecular structure of [LM(OH)]n (n = 1 or 2) and LM(.mu.-CO3)ML (M(II) = Mn, Fe, Co, Ni, Cu, Zn; L = HB(3,5-iso-Pr2pz)3)

Journal of the American Chemical Society ◽

10.1021/ja00066a018 ◽

1993 ◽

Vol 115 (13) ◽

pp. 5496-5508 ◽

Cited By ~ 193

Author(s):

Nobumasa Kitajima ◽

Shiro Hikichi ◽

Masako Tanaka ◽

Yoshihiko Morooka

Keyword(s):

Molecular Structure ◽

Carbon Dioxide ◽

Carbonic Anhydrase ◽

Metal Ion ◽

Atmospheric Carbon Dioxide ◽

Divalent Metal ◽

Divalent Metal Ions ◽

Hydroxo Complexes ◽

Catalytic Role

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Carbonic acid production and the role of carbonic anhydrase in decarboxylation in brain

Biochemical Journal ◽

10.1042/bj1140703 ◽

1969 ◽

Vol 114 (4) ◽

pp. 703-705 ◽

Cited By ~ 34

Author(s):

John W. Severinghaus ◽

F. Norman Hamilton ◽

Shamay Cotev

Keyword(s):

Thin Film ◽

Carbon Dioxide ◽

Carbonic Anhydrase ◽

Acid Production ◽

Carbonic Acid ◽

Brain Homogenate ◽

Oxidative Decarboxylation ◽

Permeable Membrane ◽

Sensitive Electrode

Sudden oxygenation of a thin film of rat brain homogenate, suspended between the surface of a glass pH-sensitive electrode and a gas-permeable membrane, is accompanied by a fall in pH, which is greater when carbonic anhydrase is inhibited. The result suggests that oxidative decarboxylation yields carbonic acid (HCO3− and H+), which dissociates to form molecular carbon dioxide. Brain carbonic anhydrase facilitates the formation of carbon dioxide from the decarboxylation products.

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Role of Carbonic Anhydrase on the Bioelectrocatalytic Reduction of Carbon Dioxide

ECS Meeting Abstracts ◽

10.1149/ma2011-01/4/145 ◽

2011 ◽

Keyword(s):

Carbon Dioxide ◽

Carbonic Anhydrase

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Silicon Substitution for Calcium in the Shell of the Fingernail Clam, Musculium Transversum Studied By X-Ray Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002488 ◽

1980 ◽

Vol 38 ◽

pp. 560-561

Author(s):

Judith A. Murphy ◽

Anthony Paparo ◽

Richard Sparks

Keyword(s):

Carbonic Anhydrase ◽

River Water ◽

Food Chains ◽

Well Water ◽

Shell Formation ◽

X Ray ◽

Molluscan Shell ◽

Fingernail Clams

Fingernail clams (Muscu1ium transversum) are dominant bottom-dwelling animals in some waters of the midwest U.S. These organisms are key links in food chains leading from nutrients in water and mud to fish and ducks which are utilized by man. In the mid-1950’s, fingernail clams disappeared from a 100-mile section of the Illinois R., a tributary of the Mississippi R. Some factor(s) in the river and/or sediment currently prevent clams from recolonizing areas where they were formerly abundant. Recently, clams developed shell deformities and died without reproducing. The greatest mortality and highest incidence of shell deformities appeared in test chambers containing the highest proportion of river water to well water. The molluscan shell consists of CaCO3, and the tissue concerned in its secretion is the mantle. The source of the carbonate is probably from metabolic CO2 and the maintenance of ionized Ca concentration in the mantle is controlled by carbonic anhydrase. The Ca is stored in extracellular concentric spherical granules(0.6-5.5μm) which represent a large amount of inertCa in the mantle. The purpose of this investigation was to examine the role of raw river water and well water on shell formation in the fingernail clam.

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Faculty Opinions recommendation of Tidal volume lower than 6 ml/kg enhances lung protection: role of extracorporeal carbon dioxide removal.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1168498.630691 ◽

2009 ◽

Author(s):

Nigel Webster

Keyword(s):

Carbon Dioxide ◽

Tidal Volume ◽

Carbon Dioxide Removal ◽

Extracorporeal Carbon Dioxide Removal ◽

Lung Protection

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CHOP-Dependent Stress-Inducible Expression of a Novel Form of Carbonic Anhydrase VI

Molecular and Cellular Biology ◽

10.1128/mcb.19.1.495 ◽

1999 ◽

Vol 19 (1) ◽

pp. 495-504 ◽

Cited By ~ 102

Author(s):

John Sok ◽

Xiao-Zhong Wang ◽

Nikoleta Batchvarova ◽

Masahiko Kuroda ◽

Heather Harding ◽

...

Keyword(s):

Carbonic Anhydrase ◽

Target Gene ◽

Target Genes ◽

Direct Evidence ◽

Nuclear Protein ◽

Intracellular Form ◽

Carbonic Anhydrase Vi ◽

Responsive Element

ABSTRACT CHOP (also called GADD153) is a stress-inducible nuclear protein that dimerizes with members of the C/EBP family of transcription factors and was initially identified as an inhibitor of C/EBP binding to classic C/EBP target genes. Subsequent experiments suggested a role for CHOP-C/EBP heterodimers in positively regulating gene expression; however, direct evidence that this is the case has so far not been uncovered. Here we describe the identification of a positively regulated direct CHOP-C/EBP target gene, that encoding murine carbonic anhydrase VI (CA-VI). The stress-inducible form of the gene is expressed from an internal promoter and encodes a novel intracellular form of what is normally a secreted protein. Stress-induced expression of CA-VI is both CHOP and C/EBPβ dependent in that it does not occur in cells deficient in either gene. A CHOP-responsive element was mapped to the inducibleCA-VI promoter, and in vitro footprinting revealed binding of CHOP-C/EBP heterodimers to that site. Rescue of CA-VIexpression in c/ebpβ−/− cells by exogenous C/EBPβ and a shorter, normally inhibitory isoform of the protein known as LIP suggests that the role of the C/EBP partner is limited to targeting the CHOP-containing heterodimer to the response element and points to a preeminent role for CHOP in CA-VI induction during stress.

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