par Claude, Albert 
Référence Advances in protein chemistry, 5, page (423-440)
Publication Publié, 1949
Référence Advances in protein chemistry, 5, page (423-440)
Publication Publié, 1949
Article révisé par les pairs
| Résumé : | Several methods are recognized that permit the separation of morphological constituents of the cell, in quantities sufficient for biochemical analysis. This chapter deals with the direct study of nature of a number of cellular complexes and the integration of biochemical functions. The reactivity of chemical compounds is determined not only by their elementary composition, but to a much greater extent, by the spatial disposition of the individual atoms within the molecule, and by the configuration of the molecule as a whole. This property that allows for considerable variations is fully utilized by biological systems and is considered the basis of the specificity of biochemical reactions. Proteins are products and constituents of cells. In the cell, proteins are the parts of the structures of considerable complexity, often in association with phospholipids or nucleic acids. Essentially, proteins and nucleic acids constitute the most popular structural constituents of the cell. However, lipids also account for as much as one-third of the cell mass, and that growing and metabolically active cells have a high phospholipid turnover. Phospholipids and ribonucleic acid are often found together in the cell, being especially concentrated in microsomes, mitochondria, and nucleoli. |
