Urea Unfolding Study of E. coli Alanyl-tRNA Synthetase and Its Monomeric Variants Proves the Role of C-Terminal Domain in Stability

Figure 5

Aminoacylation assays of WT-alaRS (a), G674D (b), N700 alaRS (c), and N461 alaRS (d) were followed at 37°C for 10 min using native alaRS (open circle), overnight incubated denatured protein containing 0.3 M urea (filled square) and 0.8 M urea (open triangle), and ten times diluted protein samples from 3 M (open square) and 8 M (filled circle) of urea. Liquid scintillation counting was used to calculate the amount of radioactivity preserved. The concentrations of alaRS and tRNA were 400 nM and 4 μM, respectively.

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