Molecular interactions, chemical/biochemical

This website describes the basic chemistry concepts required to understand biology, from the periodic table to the types of chemical bonds and molecular interactions. A biochemical gallery of the most important organic molecules for life is also included. 

Dispersion forces are ubiquitous and are present in all molecular interactions. They can occur in isolation, but are always present even when other types of interaction dominate. Typically, the interactions between hydrocarbons are exclusively dispersive and, because of them, hexane, at S.T.P., is a liquid boiling at 68.7°C and is not a gas. Dispersive interactions are sometimes referred to as hydrophobic or lyophobic particularly in the fields of biotechnology and biochemistry. These terms appear to have arisen because dispersive substances, e.g., the aliphatic hydrocarbons, do not dissolve readily in water. Biochemical terms for molecular interactions in relation to the physical chemical terms will be discussed later. 

The essence of biological processes—the basis of the uniformity of living systems—is in its most fundamental sense molecular interactions in other words, the chemistry that takes place between molecules. Biochemistry is the chemistry that takes place within living systems. To tmly understand biochemistry, we need to understand chemical bonding. We review here the types of chemical bonds that are important for biochemicals and their transformations. 

The construction of computer and CPK space-filling molecular models is based on established physical and chemical parameters. While models cannot substitute for direct experimental evidence, they can be used to describe rather successfully structures of biochemicals, molecular interactions, reaction products and many aspects of molecular d)mamics. Models may be particularly helpful in depicting the chemistry of active sites of enzymes, antibodies and receptors. Accordingly, the interaction of models described... 

The non-specific effects can be considered as the default mode of action, giving the minimal toxicity of any compound, and may be topped by specific effects that may be defined from clinical symptoms. Reactive toxicity has been ascribed to various interactions caused by a chemical s reactivity. Attempts to link the physico-chemical interactions with the physiological modes of action of toxicants have been successful so far only to a limited extent. The toxicity mechanisms attempt to deduce the compounds impacts to effects on the biochemical and biomolecular level. However, alike symptoms may result from different molecular interactions. The principal modes of action comprise ... 

The properties of supported enzyme preparations are governed by the properties of both the enzyme and the carrier material. The interaction between the two provides an immobilized enzyme with specific chemical, biochemical, mechanical and kinetic properties. The support (carrier) can be a synthetic organic polymer, a biopolymer or an inorganic solid. Enzyme-immobilized polymer membranes are prepared by methods similar to those for the immobilized enzyme, which are summarized in Fig. 22.7 (a) molecular recognition and physical adsorption of biocatalyst on a support membrane, (b) cross-linking between enzymes on (a), (c) covalent binding between the biocatalyst and the membrane, (d) ion complex formation between the biocatalyst and the membrane, (e) entrapment of the biocatalyst in a polymer gel membrane, (f) entrapment and adsorption of biocatalyst in the membrane, (g) entrapment and covalent binding between the biocatalyst and the membrane, (h) entrapment and ion complex formation between the biocatalyst and the membrane, (i) entrapment of the biocatalyst in a pore of an UF membrane, (j) entrapment of the biocatalyst in a hollow-fiber membrane, (k) entrapment of biocatalyst in microcapsule, and (1) entrapment of the biocatalyst in a liposome. 

Atomic structure—the arrangement of electrons in atoms—is an essential part of chemistry and biology because it is the basis for the description of molecular structure and molecular interactions. Indeed, without intimate knowledge of the physical and chemical properties of elements, it is impossible to understand the molecular basis of biochemical processes, such as protein folding, the formation of cell membranes, and the storage and transmission of information by DNA. 

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