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Just some stuff I thought was interesting...
This diagram is pretty basic for anyone that's studied protein but shows what I was saying pretty well;
the folded structure of the protein is disrupted but the aminos remain intact.
http://www.landfood.ubc.ca/courses/f...otein/1_41.htm
More interesting stuff;
http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract
This diagram is pretty basic for anyone that's studied protein but shows what I was saying pretty well;
Susceptibility of proteins to heat denaturation depends on a number of factors. Water greatly facilitates thermal denaturation of proteins. Dry protein powders are extremely stable to thermal denaturation. The value of Td decreases rapidly as the water content is increased from 0 to 0.35 g water/g protein. An increase in water content from 0.35 to 0.75g water/g protein causes only a marginal decrease in Td. Above 0.75g water/g protein, the Td of the protein is the same as in dilute protein solution. Some proteins are stable at temperatures as high as 100oC if the moisture content is very low.
Additive such as salts and sugars affect thermostability of proteins in aqueous solutions. Sugars such as sucrose, lactose, glucose, and glycerol stabilize proteins against thermal denaturation. Addition of 0.5 M NaCl to proteins such as b-lactoglobulin, soy proteins, serum albumin, and oat globin significantly increases their Td.
The amino acid compostition also affects thermal stability of proteins. Proteins that contain a greater proportion of hydrophobic amino acid residues, especially Val, Ile, Leu, and Phe, tend to be more stable than the more hydrophilic proteins. Other factors, such as disulfide bonds and the presence of salt bridges buried in hydrophobic clefts, may also contribute to thermostability.
Additive such as salts and sugars affect thermostability of proteins in aqueous solutions. Sugars such as sucrose, lactose, glucose, and glycerol stabilize proteins against thermal denaturation. Addition of 0.5 M NaCl to proteins such as b-lactoglobulin, soy proteins, serum albumin, and oat globin significantly increases their Td.
The amino acid compostition also affects thermal stability of proteins. Proteins that contain a greater proportion of hydrophobic amino acid residues, especially Val, Ile, Leu, and Phe, tend to be more stable than the more hydrophilic proteins. Other factors, such as disulfide bonds and the presence of salt bridges buried in hydrophobic clefts, may also contribute to thermostability.
More interesting stuff;
The use of thermal denaturation of proteins prior to in-solution digestion and mass spectral peptide mass mapping is reported. Thermal denaturation is preferred over chemical denaturation because it does not require purification/concentration prior to mass spectral analysis. Enzymatic digestions of proteins that are resistant to proteolysis are significantly enhanced by thermal denaturation. Native proteins that are sensitive to proteolysis show similar or slightly lower digestion yields following thermal denaturation. Proteins that are resistant to digestion become more susceptible to digestion, independent of protein size, following thermal denaturation. For example, amino acid sequence coverage from digest fragments increases from 15 to 86% in myoglobin and from 0 to 43% in ovalbumin. This leads to more rapid and reliable protein identification by MALDI peptide mass mapping. Although some proteins aggregate upon thermal denaturation, the protein aggregates are easily digested by trypsin and generate sufficient numbers of digest fragments for protein identification.
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