denaturation

Examples of denaturation in the following topics:

• Denaturation and Protein Folding

  • Denaturation is a process in which proteins lose their shape and, therefore, their function because of changes in pH or temperature.
  • The stomach maintains a very low pH to ensure that pepsin continues to digest protein and does not denature.
  • However, denaturation can be irreversible in extreme situations, like frying an egg.
  • The heat from a pan denatures the albumin protein in the liquid egg white and it becomes insoluble.
  • The protein in meat also denatures and becomes firm when cooked.

• Protein Folding, Modification, and Targeting

  • When a protein loses its biological function as a result of a loss of three-dimensional structure, we say that the protein has undergone denaturation.
  • Proteins can be denatured not only by heat, but also by extremes of pH; these two conditions affect the weak interactions and the hydrogen bonds that are responsible for a protein's three-dimensional structure.
  • The denatured state of the protein does not equate with the unfolding of the protein and randomization of conformation.
  • Actually, denatured proteins exist in a set of partially-folded states that are currently poorly understood.

• Enzyme Active Site and Substrate Specificity

  • Dramatic changes to the temperature and pH will eventually cause enzymes to denature.

• Homeostasis: Thermoregulation

  • Although enzyme activity initially increases with temperature, enzymes begin to denature and lose their function at higher temperatures (around 40-50 C for mammals).

• Basic Techniques to Manipulate Genetic Material (DNA and RNA)

  • The two strands can be separated by exposure to high temperatures (DNA denaturation) and can be reannealed by cooling.