Sandbox Reserved 1600: Difference between revisions

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[[Image:Hemes2.png|300 px|right|thumb|Figure 1. The active site of bd oxidase for ''Geobacillus thermodenitrificans''. Heme B558 (pink; left), Heme B595 (pink; right), and Heme D (green). Important residues shown in blue. Measurements are shown in Å.]]
[[Image:Hemes2.png|300 px|right|thumb|Figure 1. The active site of bd oxidase for ''Geobacillus thermodenitrificans''. Heme B558 (pink; left), Heme B595 (pink; right), and Heme D (green). Important residues shown in blue. Measurements are shown in Å.]]
The active site for Bd Oxidase in ''Geobacillus thermodenitrificans'' is located in subunit Cyd A. The site consists of three iron hemes: <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene>, <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene>, and <scene name='83/838655/Bd_oxidase_heme_d/1'>Heme D</scene> that are held together in a rigid triangular <scene name='83/838655/Hemes/6'>arrangement</scene> due to Van der Waals interactions. <ref name = ”Safarian” /> The <scene name='83/838655/Hemes_measurements/3'>length</scene> between each heme's central iron is relatively constant which serves to shuttle protons and electrons from one heme to another efficiently (Fig. 1). It is suggested that <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene> acts as an electron acceptor, orientated toward the extracellular side by His 186, Met 325, and Lys 252 (Fig. 1). <ref name = ”Safarian” /> With <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> closest in proximity to the intracellular side, it is suggested it functions as the proton acceptor with two potential proton pathways. It is then proposed that both <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene> and <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> shuttle their respective ions directly to <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> based on this being the shortest pathway.  
The active site for Bd Oxidase in ''Geobacillus thermodenitrificans'' is located in subunit Cyd A. The site consists of three iron hemes: <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene>, <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene>, and <scene name='83/838655/Bd_oxidase_heme_d/1'>Heme D</scene> that are held together in a rigid triangular <scene name='83/838655/Hemes/6'>arrangement</scene> due to Van der Waals interactions. <ref name = ”Safarian” /> The <scene name='83/838655/Hemes_measurements/5'>length</scene> between each heme's central iron is relatively constant which serves to shuttle protons and electrons from one heme to another efficiently (Fig. 1). It is suggested that <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene> acts as an electron acceptor, orientated toward the extracellular side by His 186, Met 325, and Lys 252 (Fig. 1). <ref name = ”Safarian” /> With <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> closest in proximity to the intracellular side, it is suggested it functions as the proton acceptor with two potential proton pathways. It is then proposed that both <scene name='83/838655/Bd_oxidase_heme_558/2'>Heme B558</scene> and <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> shuttle their respective ions directly to <scene name='83/838655/Bd_oxidase_heme_b_595/1'>Heme B595</scene> based on this being the shortest pathway.  


==Potential Oxygen Entry Site==
==Potential Oxygen Entry Site==