1 / 9

Amino Acids, Peptides and Proteins

Amino Acids, Peptides and Proteins. Titration of Amino Acids. Titration of glycine with NaOH. Isoelectric Point (pI). Isoelectric point, pI : the pH at which the majority of amino acid molecules in solution have no net charge

awomack
Télécharger la présentation

Amino Acids, Peptides and Proteins

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Amino Acids, Peptides and Proteins

  2. Titration of Amino Acids • Titration of glycine with NaOH

  3. Isoelectric Point (pI) • Isoelectric point, pI: the pH at which the majority of amino acid molecules in solution have no net charge • the pI for glycine, for example, falls between the pKa values for the carboxyl and amino groups • the following tables give isoelectric points for the 20 protein-derived amino acids

  4. Isoelectric Point (pI)

  5. Isoelectric Point (pI)

  6. Electrophoresis • Electrophoresis: the process of separating compounds on the basis of their electric charge • electrophoresis of amino acids can be carried out using paper, starch, agar, certain plastics, and cellulose acetate as solid supports • In paper electrophoresis • a paper strip saturated with an aqueous buffer of predetermined pH serves as a bridge between two electrode vessels

  7. Electrophoresis • Electrophoresis of a mixture of amino acids

  8. Electrophoresis • a sample of amino acids is applied as a spot on the paper strip • an electric potential is applied to the electrode vessels and amino acids migrate toward the electrode with charge opposite their own • molecules with a high charge density move faster than those with low charge density • molecules at their isoelectric point remain at the origin • after separation is complete, the strip is dried and developed to make the separated amino acids visible

  9. Electrophoresis • a reagent commonly used to detect amino acid is ninhydrin

More Related