Fig. 2

Purification of BAdV-4 fibre head protein by cation exchange chromatography. a. Elution profile. The absorbance measured at 280 nm and the conductivity are shown. b. Denaturing gel electrophoresis of peak fractions. In lane M, molecular weight markers of the size (in kDa) indicated on the left were loaded. In lane 1, an aliquot of the sample after nickel-affinity chromatography was loaded, eluted with imidazole. In lane 2, an aliquot of the sample eluted from the same column at pH 5 was loaded. In lanes 3 and 4, lanes 5 and 6, lanes 7 and 8, lanes 9 and 10 and lanes 11 and 12 samples from peaks a, b, c, d and e were loaded, respectively. Samples in odd lanes were heated for 5 min at 95 °C before loading, samples in even lanes were not. Putative upper and lower bands are indicated with filled and open circles, respectively. The protein runs as a monomer in all cases: the BAdV-4 fibre head does not form denaturant-stable trimers like other adenovirus fibre heads