Bioprocess Engineering: Basic Concepts, 3rd Edition

4. How Cells Work

So far you have learned something about how cells are constructed and how enzymes function. But a cell is much more than a bag filled with lipids, amino acids, sugars, enzymes, and nucleic acids. The cell must control how these components are made and how they interact with each other. Controlling and predicting the behavior of a cell is made more challenging by the phenomenon of macromolecular crowding, a condition that occurs routinely in living cells that may be essential for the efficient operation of metabolism. For example, the cytosol of the bacterium Escherichia coli contains about 300 to 400 mg/mL of macromolecules. Crowding from these high concentrations of macromolecules reduces the volume of solvent available for ...