FIG. 3.

Glycerol gradient analysis of AL2 complexes. His-AL2 protein was sedimented on 5 to 20% or 10 to 30% glycerol gradients in 150 mM NaCl in the presence or absence of 1 mM DTT, as indicated. Gradient fractions were subjected to immunoblot analysis using an anti-His tag antibody as shown below each graph, which illustrates the relative amount of AL2 in each fraction. Molecular mass standards included lysozyme (14 kDa), ovalbumin (44 kDa), bovine serum albumin (66 kDa), and β-galactosidase (120 kDa), which were sedimented in parallel gradients and monitored by absorbance at 280 nm. The positions of peak fractions corresponding to each marker protein are indicated in the graphs. (A to D) Sedimentation of wild-type AL2; (E and F) sedimentation of AL2 C33A.