Biochemistry general description

Fig. 7. General description of the electrodes and measuring cell C.T., cooling thermostat T.C., thermocouple P.S., porous stone R.T., room temperature thermostat M.S., magnetic stirring. From Larroque et al. (1976). Reprinted with permission of Analytical Biochemistry. Copyright by Academic Press.

The main purpose of this chapter is to provide an overview of present knowledge of the mechanisms of microbially influenced corrosion on common constructional materials. This review includes both metallic and nonmetallic materials. The reason for including nonmetallic materials is that biodegradation occurs on these materials and that they are widely used for constmction purposes. Because detailed knowledge in the fields of microbiology and biochemistry is necessary in order to understand the mechanisms of microbially influenced corrosion, considerable space has been devoted to a general description of microorganisms and to a... 

Pullman and Pullman (1963), in their seminal book on quantum biochemistry, noted the central role occupied in life processes by molecules possessing partly or completely conjugated systems. These molecules include the coenzymes, whose precursors are the water-soluble vitamins. Stabilization of transition states by electronic delocalization, transmission of electronic perturbations over several atoms, and facilitation of electron mobility were suggested as explaining, at least in part, the reaction capabilities of coenzymes. An additional role for coenzymes (Jencks, 1975) is the provision for optimal binding interactions with specific subsites on the enzyme, the so-called "anchor principle" discussed above. In this section, we shall consider the mechanism of action of the major coenzymes. A general description of coenzyme reaction mechanisms is available (Lowe and Ingraham, 1974). 

The International Union of Biochemistry and Molecular Biology (IUBMB) developed a system of nomenclature in which enzymes are divided into six major classes (Figure 5.1), each with numerous subgroups. The suffix -ase is attached to a fairly complete description of the chemical reaction catalyzed, for example D-glyceraldehyde 3-phosphate NAD oxidoreductase. The IUBMB names are unambiguous and informative, but are sometimes too cumbersome to be of general use. 

By structure is meant not only the disposition of covalent bonds, but also conformation, at the small molecule and at the macromolecular level. By mechanism is meant a description of reactive intermediates and transition states - evidence-based curly arrows. It is with some reservation that the word carbohydrate is in the title, as strictu sensu carbohydrate biochemistry includes much of primary metabolism, such as glycolysis or the Calvin cycle. These reactions are in general not covered there are several excellent curly-arrow-based biochemistry texts available. 

Equivalent terms used by chemists for the gel-chromatography technique are gel filtration (biochemistry term), gel-permeation chromatography (polymer chemistry term), and molecular sieve chromatography. Size-exclusion chromatography is a general term for the technique, and it is perhaps the most descriptive term for what occurs on a molecular level. 

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