Sandbox 666: Difference between revisions
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The N-terminal section of each subunit forms, with a β-hairpin, an “arm” which wraps around the DNA molecule. (The arm brings the DNA molecule to the catalytic cleft.) | The N-terminal section of each subunit forms, with a β-hairpin, an “arm” which wraps around the DNA molecule. (The arm brings the DNA molecule to the catalytic cleft.) | ||
The specific recognition of EcoRI of the GAATTC sequence is mediated by twelve hydrogen bonds (six bonds per subunit) originating from α helical recognition modules. Three amino acids are responsible for the recognition:<scene name='Sandbox_666/Grey_protein/ | The specific recognition of EcoRI of the GAATTC sequence is mediated by twelve hydrogen bonds (six bonds per subunit) originating from α helical recognition modules. Three amino acids are responsible for the recognition:Arg200, Glu144 and Arg145<scene name='Sandbox_666/Grey_protein/3'>TextToBeDisplayed</scene> each residue form two hydrogen bonds with Guanine and the adjacent Adenosine residues respectively. | ||
The reaction is due to a catalytic sequence motif which is found in most type II restriction endonucleases: the PD…D/EXK motif. For EcoRI, this catalytic sequence is PD91 …E111AK.<scene name='Sandbox_666/Catalytic_core/3'>The catalytic core is shown here in red</scene>. This motif is also responsible for Mg2+ binding(Asp90 and Glu111). | The reaction is due to a catalytic sequence motif which is found in most type II restriction endonucleases: the PD…D/EXK motif. For EcoRI, this catalytic sequence is PD91 …E111AK.<scene name='Sandbox_666/Catalytic_core/3'>The catalytic core is shown here in red</scene>. This motif is also responsible for Mg2+ binding(Asp90 and Glu111). | ||
