Denaturation cause

Denaturation is the irreversible precipitation of proteins caused by heating, such as the coagulation of egg white as an egg is cooked, or by addition of strong acids, bases, or other chemicals. This denaturation causes permanent changes in the overall structure of the protein and because of the ease with which proteins are denatured it makes it difficult to study natural protein structure. Nucleic acids also undergo denaturation. 

Loss of Mediator Activity and Leaching Many in vivo electrochemical glucose sensors utilize a mediator to shuttle the electron to the electrode and decrease the interference by electro-oxidizing species.28 When small mediators are used, the mediators tend to diffuse out of the membrane and into the body. If the mediator enters the body, it may result in interference with biological reactions.28-30 The method of attachment for the mediator is very important because if the mediator leaches out or loses activity, the sensor may fail. The mediator may lose activity if it undergoes a detrimental reaction or denatures, causing the potential to shift or the electron mediator ability to be lost. 

One other salient feature of freeze-drying is that the product retains its original texture and regains its initial morphology upon addition of an appropriate amount of a solvent (usually water). In fact, freeze-drying avoids the denaturation caused by the heating procedures used in conventional drying methods. 

Irreversible precipitation of proteins, called denaturation, is caused by heat, strong acids or bases, or various other agenis. Coagulation of egg white by heat, for example, is denaturation of the protein egg albumin. The extreme ease with which many proteins are denatured makes their study difficult. Denaturation causes a fundamental change in a protein, in particular destroying any physiological activity. (Denaturation appears to involve changes in the secondary structure of proteins, Sec. 36.16.)... 

The CCC technique is well suited for the separation of peptides and related compounds because it eliminates sample loss and denaturation caused by the solid support used in conventional liquid chromatography. The method separates multigram quantities of peptide samples using pH zone-refining CCC. 

Denaturation refers to a dismption of the tertiary and secondary structure of the protein molecule. The denaturation can be reversible or irreversible. Denaturation caused by, for example, an increase of temperature is said to be reversible if the native stmcture is regained on decreasing the temperature. Irreversible denamration implies that the unfolding process is such that the native structure cannot be regained simply by lowering the temperamre (although it may sometimes be possible to remrn the protein to its native state... 

Hypochromism - absorption of light by bases reduced when in helix = denaturation causes increase in absorbance of light at 260 nm. 

The heme has a coordinated iron ion at the center that binds to oxygen. Proteins can be denatured by heat, pH, and chemicals. Denaturation causes the protein to lose its native tertiary structure. 

The latter facilitates conformational movements during catalysis (such as the induced fit , see below) thereby underlining the pronounced dynamic character of enzyme catalysis. Besides the main polyamide backbone, the only covalent bonds are -S-S- disulfide bridges. Enzymes are intrinsically unstable in solution and can be deactivated by denaturation, caused by increased temperature, extreme pH, or an unfavorable dielectric environment such as high salt concentrations. 

ILLUSTRATIVE EXAMPLE 19.19 At 98.6°F (Ti), an important neural activator is found to have a specific reaction rate of 0.25 (min) with Ea = 20,000 Btu/lbmol. It has been determined that after the reaction rate reaches 0.32 (min) , the activator irreversibly denatures, causing coma and eventually death. How high a fever (T2) can a human withstand before this condition occurs ... 

From the emission spectra in fig. 3 it is concluded that the nativeness of the RC s in the crystal is not seriously harmed since both peaks are present and no shifts beyond experimental error are observed. Partial denaturation caused both peaks to disappear without a change in relative intensities. 

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