Bicarbonate biochemistry

Hienerwadel R, Berthomieu C. (1995) Bicarbonate binding to the non-heme iron of photosystem II investigated by Fourier transform infrared difference spectroscopy and C-labeled bicarbonate. Biochemistry 16288-16297. Stadtman ER. (1993) Oxydation of free amino acids and amino acid residues in proteins by radiolysis and by metal-catalysed reactions. Anna Rev Biochem 62 797-821. 

Beryllium difiuoride, dipole in, 293 Berzelius, Jons, 30 Bessemer converter, 404 Beta decay, 417 Bela particle, 417 Bicarbonate ion, 184 Bidentaie. 395 Billiard ball analogy, 6, 18 and kinetic energy, 114 Billiard ball collision, conservation of energy in, 114 Binding energy, 121, 418 Biochemistry, 421 Bismuth, oxidation numbers, 414 Blast furnace, 404 Bohr, Niels, 259 Boiling point, 67 elevation, 325 normal, 68... 

The first recognition of a role for zinc in biochemistry was the discovery inl939 that it was an essential component of carbonic anhydrase, a key enzyme in erythrocytes that catalyses the formation of bicarbonate ... 

As an example, bulk modification by the organic reaction of unsaturated PHA with sodium permanganate resulted in the incorporation of dihydroxyl or carboxyl functional groups [106]. Due to the steric hindrance of the isotactic pendant chains, complete conversion could not be obtained. However, the solubility of the modified polymers was altered in such a way that they were now completely soluble in acetone/water and water/bicarbonate mixtures, respectively [106]. Solubility can play an important role in certain applications, for instance in hydrogels. Considering the biosynthetic pathways, the dihydroxyl or carboxyl functional groups are very difficult to incorporate by microbial synthesis and therefore organic chemistry actually has an added value to biochemistry. 

The sodium acetate-acetic acid combination is one of the most widely used buffers, and is usually referred to simply as acetate buffer. Other buffer combinations commonly employed in chemistry and biochemistry include carbonate-bicarbonate (sodium carbonate-sodium hydrogen carbonate), citrate (citric acid-trisodium citrate), phosphate (sodium dihydrogen phosphate-disodium hydrogen phosphate), and tris [tris(hydroxymethyl)amino-methane-HCl]. 

Although it was previously thought that this step did not require ATP, more recent work has shown that ATP is necessary for the reaction to go at physiological concentrations of bicarbonate. Voet, D and Voet, J. G. 1995. Biochemistry, 2nd ed John Wiley Sons, New York, p. 800. 

Scheme 2 Proposed mechanism for bicarbonate-mediated peroxidation in SOD. After Cu(II) reduction (i), bicarbonate binds to the anion-binding site (ii). In (iii), HOO" reacts with bicarbonate to form peroxycarbonate (iv). In (v), the oxygen radical species formed [O ] may oxidize endogenous or exogenous substrates. This leaves bicarbonate bound to the anion-binding site (vi). (Ref 17. Reproduced by permission of American Society for Biochemistry Molecular Biology)...

Courtois E, Ploux O. Escherichia coli cyclopropane fatty acid synthase is a bound bicarbonate ion the active-site base Biochemistry 2005 44 13583-13590. 

A brilliant success of modern biochemistry has been to show that all or almost all proteins of bovine pancreatic juice are enzymes (1). It may be said in a cursory way that this juice is a solution of enzymes in bicarbonate and that its composition is strictly utilitarian. Bicarbonate is present in order to neutralize hydrochloric acid coming from the stomach and to keep enzymes in solution. Enzymes are present for digesting alimentary products in the intestine. On the other hand, pancreatic juice seems to have been created for the protein chemist s delight, since its proteins are biologically active, relatively simple, and endowed with unusual properties. 

J Xiong, S Subramaniam and Govindjee (1996) Modeling of the D1/D2 proteins and cofactors ofthe photosystem II reaction center. Implications for herbicide and bicarbonate binding. Protein Sci 5 2054-2073 FI Michel and J Deisenhofer (1988) Relevance ofthe photosynthetic reaction centers from purple bacteria to the structure of photosystem II. Biochemistry 27 1-7... 

TRIS is one of the most common buffers used in the biology/biochemistry labs. It is used as alternative to sodium bicarbonate in the treatment of metabolic acidosis. It is also an emulsifying agent and absorbent for acidic gases, alkalizer and osmotic diuretic. 

The renal compensation is now the opposite, with the kidney losing bicarbonate. As with the original compensation, it takes a few days for renal mechanisms to have their effects in full and for normal blood biochemistry to be restored. During this time, the acid base status gradually moves along the line from point C to point N in Figure 3.3. 

Hochman Y and Carmeli C (1981a) Modulation by bicarbonate, phosphate and maleate of the kinetics of ATPase activity and the binding of manganese ions to coupling factor 1. Biochemistry 20, 6293-9297. 

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