An Archaeal Homolog of Proteasome Assembly Factor Functions as a Proteasome Activator (original) (raw)
Figure 5
PbaB exerts a chaperone function through the C-terminal segments.
(A) Aggregation of citrate synthase (CS, 50 nM) incubated at 50°C was monitored by measuring absorbance at 500 nm for 15 min; 1∶0 molar ratio (CS monomer:PbaB tetramer, circles), 1∶0.25 (triangles), 1∶0.5 (squares), 1∶1 (inverted triangles), and 1∶2 (diamonds). (B) Similar experiments were performed using the C-terminal deletion mutants of PbaB (1∶1 molar ratios); buffer (circles), wild-type PbaB (triangles), CΔ3 (squares), CΔ8 (inverted triangles), and CΔ42 (diamonds). (C) Similar results were obtained in three experiments. The graph indicates the values at 15 min. Error bars represent s.e.m.