Sandbox Reserved 951: Difference between revisions
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== Global Structure == | == Global Structure == | ||
== | == Structure related to functions == | ||
The most known reaction of luciferase is the light emission where luciferase uses luciferin, ATP and O2 as substrates. The color of emitted light varies according to the pH, which can be explained by the luciferase structure. But there are some other reactions which can uses fatty acids and coenzyme A. So the active site of the luciferase can theorically bind all these compounds. | The most known reaction of luciferase is the light emission where luciferase uses luciferin, ATP and O2 as substrates. The color of emitted light varies according to the pH, which can be explained by the luciferase structure. But there are some other reactions which can uses fatty acids and coenzyme A. So the active site of the luciferase can theorically bind all these compounds. | ||
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===Interactions with ligands=== | ===Interactions with ligands=== | ||
The active site is not strictly highlighted according to the actual state of studies but some residues and motifs strongly modified have been determined and this conformation enables to find the active site. Many of these conserved residue are located on the core of the β-barrel and on the small C-terminal domain and in the surface of the N-terminal domain, which forms a depression. | The active site is not strictly highlighted according to the actual state of studies but some residues and motifs strongly modified have been determined and this conformation enables to find the active site. Many of these conserved residue are located on the core of the β-barrel and on the small C-terminal domain and in the surface of the N-terminal domain, which forms a depression. However, this depression is too large to enable interactions between residues and substrates, so it is thought that a conformational change occurs and sandwiches the substrates, forming the active site. This conformational change provide a suitable environment for light production because of water molecules will be excluded from the active site, favouring intramolecular reactions. Residues also follow a <scene name='60/604470/Cleft/1'>cleft</scene> caused by of the <scene name='60/604470/Beta_sheet_b/2'>β-sheet</scene> against the <scene name='60/604470/Beta_barrel/2'>β barrel</scene>. | ||
=====Interaction with ATP===== | =====Interaction with ATP===== | ||
We find a signal motif in luciferase which is <scene name='60/604470/Atp_binding_signal_motif/1'>[STG]-[STG]-G-[ST]-[ST]-[TSE]-[GS]-x-[PALIVM]-K</scene> where some residue like lysine are always conserved. This pattern enables ATP binding thanks to hydrogen bonds between residues and phosphates of ATP. There is another pattern : [YFW]-[GASW]-x-[TSA]-E which takes a particular conformation because of hydrogen bonds between residues and maintain the adenosin ring of ATP. | We find a signal motif in luciferase which is <scene name='60/604470/Atp_binding_signal_motif/1'>[STG]-[STG]-G-[ST]-[ST]-[TSE]-[GS]-x-[PALIVM]-K</scene> where some residue like lysine are always conserved. This pattern enables ATP binding thanks to hydrogen bonds between residues and phosphates of ATP. There is another pattern : [YFW]-[GASW]-x-[TSA]-E which takes a particular conformation because of hydrogen bonds between residues and maintain the adenosin ring of ATP. | ||
