BIOLOGY 173 Lecture Notes - Lecture 8: Starch, Column Chromatography, Penicillin
Document Summary
W 8pm- mb3 demo for mt sections in your lab room. Column chromatography is a method of separating and purifying proteins based on some property they possess. This can be size, charge, hydrophobicity, or binding specificity. A cell extract containing many different proteins is loaded on a column containing a bead matrix. Some proteins stick to the beads while others pass through (are eluted from the column). In a second pass, conditions can be changed, so that some proteins no longer stick to the beads and will be eluted. This can be repeated many times, e. g. , changing salt concentration in small steps, to divide the original extract into many fractions. The protein we have been looking at, gfp, turns out to be fairly hydrophobic. We will use this property as the basis for purifying it. Under regular salt conditions, gfp will fold so that its hydrophobic residues face inward and do not interact with water.
