Figure 6From: On the evolutionary conservation of hydrogen bonds made by buried polar amino acids: the hidden joists, braces and trusses of protein architectureExamples of hydrogen bond interactions from conserved, buried residues within edge strands to mainchain atoms. Representative structures were chosen for each family based on resolution; residues are coloured by atom type with buried, conserved polar residues shown in magenta. Hydrogen bonds are shown in black. A) An asparagine forms hydrogen bonds to mainchain atoms in a type IV β-turn in aspartate/ornithine carbamoyltransferases [PDB: 1oth]. Within the cyclodextrin glycosyltransferases [PDB: 1qhp] B) an asparagine forms hydrogen bonds to mainchain atoms within a complicated β-hairpin structure (strands and hairpin shown in purple). C) A tryptophan forms hydrogen bonds to a turn joining two β-strands in the cyclodextrin glycosyltransferases [PDB: 1qhp]. D) Histidine forming hydrogen bonds to a 310 helix in the Cu/Zn superoxide dismutase family [PDB: 2aps]. Two examples of glutamine residues forming hydrogen bonds to mainchain atoms in another strand within a β-sandwich in E) the picornavirus coat protein family (also forms hydrogen bonds to mainchain atoms within a 310 helix and coil region) [PDB: 2plv] and F) the immunoglobulin domain (V set) light chain family [PDB: 6fab].Back to article page