In Biochemistry

High-specific activity radiotracers, produced by neutron activation, have been used with great success to study biochemical processes in the small animal model. For example, Se, having a specific activity of 1,000 Cig has been used to advance the discovery of dependent enzymes and other biologically important proteins. Trace-element and mineral nutrition are important aspects of human and animal health. NAA has been used to characterize a wide variety of samples for their elemental content. The basic nutritional requirement at the cellular level can be studied using NAA and radiotracer techniques. NAA is one of the important methods that has been used to study nutritional bio-availability and absorption of essential trace elements in the human using enriched stable isotopes. 

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Besides such textual databases that provide bibhographic information, sequence databases have attained an even more important role in biochemistry. Sequence databases are composed of amino add sequences of peptides or proteins as well as nudeotide sequences of nudeic acids. The 20 amino adds are mostly represented by a three-letter code or by one letter according to the biochemical conventions) the four nudeic adds are defined by a one-letter code. Thus the composition of a biochemical compound is searchable by text retrieval methods. 

Some of the most important organic compounds in biochemistry are the a ammo acids rep resented by the general formula shown... 

In biochemistry this unit is called the dalton, with symbol Da. 

There are several forms of electrophoresis. In slab gel electrophoresis the conducting buffer is retained within a porous gel of agarose or polyacrylamide. Slabs are formed by pouring the gel between two glass plates separated by spacers. Typical thicknesses are 0.25-1 mm. Gel electrophoresis is an important technique in biochemistry, in which it is frequently used for DNA sequencing. Although it is a powerful tool for the qualitative analysis of complex mixtures, it is less useful for quantitative work. 

H. J. M. Bowen, Trace TUements in Biochemistry, Academic Press, Inc., New York, 1966. 

L. J. Eilet, Jr. and co-wotkets. Glutamic Acid Advances in Biochemistry and Physiology, Raven Press, New York, 1979. 

Recognition of the thio group s key role in biochemistry has led to studies of l,4-ben2oquinone with glutathione, a tripeptide 7-Glu-Cys-Gly (GSH). The cross-oxidation of the initial addition product by excess quinone leads, under physiological conditions, to all three isomeric products (46), ie, the 2,3-and 2,6-isomers as well as the 2,5-disubstituted l,4-ben2oquinone shown. 

Chiral Chromatography. Chiral chromatography is used for the analysis of enantiomers, most useful for separations of pharmaceuticals and biochemical compounds (see Biopolymers, analytical techniques). There are several types of chiral stationary phases those that use attractive interactions, metal ligands, inclusion complexes, and protein complexes. The separation of optical isomers has important ramifications, especially in biochemistry and pharmaceutical chemistry, where one form of a compound may be bioactive and the other inactive, inhibitory, or toxic. 

T artrazine, 4,5-dihydro-5 -oxo-1 -(4-sulfophenyl)-4-[(4-sulfophenyl)azo]-1// -pyrazole-3-carboxylic acid trisodium salt was discovered by Ziegler in 1884 and is used as a dye for wool and silk. It is used as a colour additive in foods, drugs and cosmetics, and is an adsorption-elution indicator for chloride estimations in biochemistry (B-76MI40404). 

The most numerous cases of homogeneous catalysis are by certain ions or metal coordination compounds in aqueous solution and in biochemistry, where enzymes function catalyticaUy. Many ionic effects are known. The hydronium ion and the hydroxyl ion OH" cat-... 

Completely trivial names continue in use for good reasons, of which an important one is the need for a simple name for frequent communication concerning a commonly encountered compound or structure. For obscure compounds there is surely neither need nor desirability to perpetuate trivial names, and coining new trivial names is almost never justified. Let us, however, consider purine , the trivial name for what might more systematically be named imidazo[5,4-ring system is so important in biochemistry that exclusive use of one of the systematic names would be intolerable. If the name purine were not available, another short trivial name would inevitably be coined, or even an acronym ( IP or TAP ). It is better to retain the name sanctioned by roughly a century of use, and benefit from a link in comprehension with the past. 

Heteropolyacids (HPA) are the unique class of inorganic complexes. They are widely used in different areas of science in biochemistry for the precipitation of albumens and alkaloids, in medicine as anticarcinogenic agents, in industry as catalysts. HPA are well known analytical reagents for determination of phosphoms, silica and arsenic, nitrogen-containing organic compounds, oxidants and reductants in solution etc. 

The reduction of dimensions also reduces volumes which are accessible to the detector. Thus, detection principles related to geometric dimensions of the detector cell ai e not ideally suited for coupling to microsystems, whereas surface sensitive principles, such as electrochemical methods or optical methods utilizing the evanescent field of a waveguide, or methods which can be focussed on a small amount of liquid, such as electrochemiluminescence (ECE), ai e better suited. This is why electrochemiluminescence detectors ai e combined to microsystems. Moreover ECE has found wide applications in biochemistry because of its high sensitivity, relatively simplicity and feasibility under mild conditions. 

The aristocrats who determine crystal structures have garnered a remarkable number of Nobel Prizes no fewer than 26 have gone to scientists best described as crystallographers, some of them in physics, some in chemistry, latterly some in biochemistry. Crystallography is one of those fields where physics and chemistry have become intimately commingled. It has also evinced more than its fair share of quarrelsomeness, since many physicists regard it as a mere technique rather than a respectable science, while crystal structure analysts, as we have seen, were for years inclined to regard anyone who studied the many other aspects of crystals as second-class citizens. 

Huang, T J Dong, Z X, Shreeve, J M Inorg Chem 1987,26, 2604 Denson, D D, Uyemo, E T, Simon, R L, Peters, H M In Biochemistry Involving Carbon-Fluorine Bonds, Filler, R, Ed, ACS Symposium Se Ties 8, American Chemical Society Washington, DC, 1976 p 190 Van DerPuy, M 7 Fluorine Chem 1979,13 375 Shustov, L D, Nikolenko, L N, Senchenkova, T M Zh Obshch Khim 1983, 5i m.Chern Abstr 1983, 9S 143326v... 

Pentafluorophenyl derivatives have received wide application in biochemistry as highly selective and efficient protective reagents (for a review, see reference 148)... 

Guy, W S Taves, D R Brey, W S, Jr, In Biochemistry Involving Carbon-Fluorine Bonds Filler, R, Ed ACS Symposium Senes 28, Amencan Chemical Society, Washington, DC, 1976. 

One year later, 22-year-old James Watson completed his Ph.D. studies on bacterial viruses at Indiana University and began postdoctoral research in biochemistry in Copenhagen. After a year at Copenhagen, Watson decided Cambridge was the place to be. 

Bloch, K., 1994. Blondes in Venetian Paintings, the Nine-Banded Armadillo, and Other Essays in Biochemistry. New Haven Yale University Pre.ss. 

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