BIOC 2580 Lecture Notes - Lecture 4: Molar Mass, Differential Centrifugation, Ultracentrifuge

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 2580
• Professor: John Dawson

Document Summary

Electrophoresis: separation based on movement of charged molecules in an electric fields: rate of movement depends on size, shape and charge, to prevent movement of the solution, the separation is carried out in a porous gel. Polyacrylamide gel is easily prepared in lab, has right porosity for proteins 10 kda - 1000 kda: a typical gel is 5-15% polymer and 90-95% water with conductive buffer. In sds-polyacrylamide gel electrophoresis (sds-page) the protein is pre-treaed with detergent. Two dimensional gels: separation of complex samples: combines isoelectric focusing and sds electrophoresis, can separate individual proteins in very complex mixture. A protein is a long linear chain of amino acids. Protein structure is organized in the three (or four) levels. To investigate the structure of a protein, we find out which amino acids are present and in what. An atom with a lone pair may use it in different ways**: as an h-bond acceptor if it simply attracts an o-h or n-h.