Fig. 5: Comparison of interactions of mSerRS with mtRNASer(UGA) and mtRNASer(GCU).
a Superposition of the mSerRS-mtRNASer(UGA) and mSerRS-mtRNASer(GCU) complexes. The body of mSerRS is shown in light blue (subunit 1) and wheat (subunit 2), the helical arms are colored differentially in light green (UGA complex) and light tomato (GCU complex), respectively. mtRNASer(UGA) is colored in green, mtRNASer(GCU) in tomato (PDB 7U2A)35. The superposition is based on the catalytic core domains of the mSerRS dimer. b Close-up view of the helical arm-elbow interface in both complexes as shown in a, highlighting the conformational changes in the helical arm induced by tRNA binding (arrows). The helical arm of the free mSerRS (PDB 7TZB) is shown in white. c Close-up view of the helical arm-elbow interface in a superposition based on the helical arm (shown white cartoon with transparent surface). The side chains of Lys110 (K110) and Arg146 (R146) are shown as spheres and colored green for the mtRNASer(UGA) complex and tomato for the mtRNASer(GCU) complex. d Summary of charging experiments for mtRNASer(UGA) mutants by wild-type mSerRS. e Summary of mtRNASer(UGA) mutants used in d. ‘GC’ denotes stabilized ‘wild-type’ tRNA (see Supplementary Fig. 1 and Methods). f Charging kinetics for mSerRS variants on mtRNASer(UGA) (green) and mtRNASer(GCU) (tomato; data taken from Ref. 35). 3xRA denotes the R118A, R139A, R143A triple mutant. Data are presented as mean values+/-SD from triplicate experiments. Individual data points are shown as open circles. Source data are provided as a Source Data file. See also Supplementary Tables 3 and 4.
