Figure 5
Deuterium-exchange mass spectrometry (DXMS) analysis. DXMS was used to guide the construct design used for determining the crystal structure of a putative ethanolamine-utilization protein from Salmonella typhimurium. (a) The left side of the figure shows that the N-terminal portion of the protein is more disordered, or unstructured in solution, as the backbone amide protons are more susceptible to exchange. Deuterium-labelled proteolytic fragments are highlighted in red. (b) The right side of the figure shows that the C-terminal portion of the protein is more ordered, or structured in solution, as the backbone-amide protons are less susceptible to exchange. The region selected for truncation is denoted by a blue arrow. (c) Ribbon diagram of the final crystal structure determined for residues 98–229 showing the compact and ordered structure (loops are shown in green, α-helices in red and β-strands in yellow; PDB entry 2pyt
; Joint Center for Structural Genomics, unpublished work). (d) The same structure colored according to the B-factor value, highlighting the stable core of the protein in blue and the more flexible outer regions in green through red. Data kindly provided by Scott Lesley of the Joint Center for Structural Genomics (JCSG). |