User:Matt Whelihan: Difference between revisions
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One of the most studied of all luciferases is that of the Japanese <scene name='User:Matt_Whelihan/Rainbow_n-c/1'>Firefly</scene> ''Luciola cruciata''. This particular luciferase enzyme is located in the light emitting organ known as the lantern in the abdomen of the beetle. Firefly larvae glow green to ward off predators and adult fireflies use this mechanism of bioluminescence to attract mates. Luciferase binds ATP/Mg+ and D-luciferin and oxidizes it to Oxyluciferin with the products of one photon of yellow-green light, pyrophosphate, AMP and CO2<ref>PMID:775940</ref>. | One of the most studied of all luciferases is that of the Japanese <scene name='User:Matt_Whelihan/Rainbow_n-c/1'>Firefly</scene> ''Luciola cruciata''. This particular luciferase enzyme is located in the light emitting organ known as the lantern in the abdomen of the beetle. Firefly larvae glow green to ward off predators and adult fireflies use this mechanism of bioluminescence to attract mates. Luciferase binds ATP/Mg+ and D-luciferin and oxidizes it to Oxyluciferin with the products of one photon of yellow-green light, pyrophosphate, AMP and CO2<ref>PMID:775940</ref>. | ||
''L. cruciata'' luciferase is a 62 kDa monooxygenase with two distinct domains. | ''L. cruciata'' luciferase is a 62 kDa monooxygenase with two distinct domains. | ||
<scene name='User:Matt_Whelihan/N-terminal_domain/1'>N-terminal domain</scene> (residues 4-436) is comprised of of an antiparalell β-barrel and two β-sheets, flanked by α-helices. The | <scene name='User:Matt_Whelihan/N-terminal_domain/1'>N-terminal domain</scene> (residues 4-436) is comprised of of an antiparalell β-barrel and two β-sheets, flanked by α-helices which forms a typical Rossmann fold [[Image:Rossmanfold.jpg]][http://en.wikipedia.org/wiki/Rossmann_fold.] The | ||
<scene name='User:Matt_Whelihan/C-terminal_domain/2'>C-terminal domain</scene> (residues 440-544) is comprises of a separate α-β hinge<ref>PMID:8805533</ref>. | <scene name='User:Matt_Whelihan/C-terminal_domain/2'>C-terminal domain</scene> (residues 440-544) is comprises of a separate α-β hinge<ref>PMID:8805533</ref>. | ||
The <scene name='User:Matt_Whelihan/Secondary_structure/1'>structure</scene> | The <scene name='User:Matt_Whelihan/Secondary_structure/1'>structure</scene> | ||
''P. pyralis'' luciferase shares significant sequence and mechanistic homology with peptide synthetases and acylCoA ligases. These enzymes belong to a superfamily of adenylate-forming enzymes that catalyze activation reactions between ATP and a carboxyl group of their substrates. Despite high sequence homology, there are only seven residues that are conserved across this superfamily (Gly200, Lys206, Glu344, Asp422, Arg437, Gly446, and Glu455). These residues are believed to be integral to the binding of ATP and the formation of an adenylate compound. <ref>PMID:1447981</ref>. These seven highly conserved amino acids identify the | ''P. pyralis'' luciferase shares significant sequence and mechanistic homology with peptide synthetases and acylCoA ligases. These enzymes belong to a superfamily of adenylate-forming enzymes that catalyze activation reactions between ATP and a carboxyl group of their substrates. Despite high sequence homology, there are only seven residues that are conserved across this superfamily (Gly200, Lys206, Glu344, Asp422, Arg437, Gly446, and Glu455). These residues are believed to be integral to the binding of ATP and the formation of an adenylate compound. <ref>PMID:1447981</ref>. These seven highly conserved amino acids identify the | ||
<scene name='User:Matt_Whelihan/Active_site_residues/1'>active site</scene> which is located in the large cleft between the two adjacent N and C-terminal domains. | <scene name='User:Matt_Whelihan/Active_site_residues/1'>active site</scene> which is located in the large hydrophobic cleft between the two adjacent N and C-terminal domains. | ||
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