Sandbox 666: Difference between revisions

EcoRI is a homodimer, so it has two identical subunits (Representation of one <scene name='Sandbox_666/Monomer_structure/4'>subunit</scene>) of 31 kDa, but it possible to have homotetramers at high concentrations. The constitutive monomers are 276 amino acids long. EcoRI and all the other restriction enzymes show a common structural core which is a  α/β domain. The constitutive subunits of EcoRI are organized into a single α/β domain (five stranded <scene name='Sandbox_666/B_sheet/1'>β</scene> sheet which is surrounded  by <scene name='Sandbox_666/Helix/1'>α helices</scene> ). Four of these five β strands are parallel whereas the fourth (β4) is in an anti-parallel orientation to the others.<ref>Refinement of Eco RI endonuclease crystal structure: a revised protein chain tracing.