Journal: Nucleic Acids Research

Article Title: Structural insights into RNA-dependent eukaryal and archaeal selenocysteine formation

doi: 10.1093/nar/gkm1122

Figure Lengend Snippet: The oligomeric states of SepSecS and related enzymes. ( A ) The overall architecture of the MMPSepSecS tetramer. Chains A and B, and chains C and D form dimers, respectively. The PLP molecules bound to each subunit are shown as ball and stick models. Chain A, chain B, chain C and chain D are colored pink, blue, green and yellow, respectively. ( B ) The N-terminal extension domains of chains B and C form a hydrophobic core that stabilizes the tetrameric state of MMPSepSecS. Three α-helices (α1,α2,α4) are labeled. Chains B and C are colored blue and green, respectively. ( C ) Stereo view of the AFSepCysS dimer in the same orientation as (A) . Chains A and B are colored pink and blue, respectively. The PLP molecules are shown as ball and stick models. ( D ) Stereo view of the ECCsdB dimer in the same orientation as (A) . The coloring scheme and the PLP representation are the same as in (C). ( E ) Gel filtration of selenomethionine-labeled SepSecS on Sephacryl S-300. Absorbance at 280 nm is shown as a blue line. The elution volumes of other oligomeric proteins are indicated in the chromatogram. The molecular weight of the MMPSepSecS monomer is 50 kDa. MMPSepSecS eluted at the size expected for a tetrameric species.

Article Snippet: A 0.5 ml sample of a 1.5 mg/ml purified solution of selenomethionine-labeled MMPSepSecS was loaded onto a HiPrep 16/60 Sephacryl S-300 HR column (GE Healthcare).

Techniques: Labeling, Filtration, Molecular Weight