Physical Chmesitry Of Proteins Flashcards
What is the process called in which proteins are synthesised? And what are the examples?
Translation
Phosphorylation Glycosylation Hydroxylation Methylation Disulfide bond formation between two cys
What charge does a protein with lots of basic groups have?
Positive
What does a proteins state of ionisation determine?
Amino acid
pH of solution environment
What is the isoelelectric point? What are the disadvantages?
The pH at which a molecule or surface carries no net electrical charge
Does not migrate in electrical field
Least soluble
What does the additional two arginines in insulin glargine do?
Increase IEP of insulin and makes it more soluble in acidic conditions but less soluble upon injection
What is gel electrophoresis?
Method of separation and analysis of macromolecules
Separated by charge and size, in matrix or gel, in an electric field charged molecules move towards anode or cathode
What effects the force of attraction and retardation?
Attraction: size of charge and size of electric field
Retardation: friction and regulation of medium
How does polyacrylamide gel electrophoresis (PAGE) work?
Native structure of protein maintained, separation according to size and charge
How does SDS polyacrylamide gel electrophoresis work?
Native structure of protein not maintained and separation according to size
What does sodium dodecyl sulfate do?
Emulsifies and gives proteins a net negative charge
What are the typical detection methods post electrophoresis?
Coomassie brilliant blue dye staining
Western blot
How to measure protein conc?
UV absorption
Colorimetric methods
Define the Henderson Hasslebalch equation
pH=pKa +log [A-]/[HA]
