Tutorial:How do we get the oxygen we breathe: Difference between revisions
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=====Hemoglobin is a tetramer===== | =====Hemoglobin is a tetramer===== | ||
In the three-dimensional structure of hemoglobin to the right, you see two <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_light_blue_chains/2'>light-blue chains</scene> and two <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_light_green_chains/1'>light-green chains</scene>. (''Drag the hemoglobin structure with the mouse to rotate it. To zoom, use your scroll-wheel, or drag while holding shift.'') These are the <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_four_monomers/1'>four monomers</scene> of the hemoglobin molecule, and they are shown in a cartoon-style representation where a single curved line connects the α-carbons in the amino acids of each chain and the [[secondary structure]] α-helices are shown as simplified cartoon helices. Because hemoglobin is composed of four monomers, it is called a <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_tetramer/2'>tetramer</scene>. The two types of monomers that make up the hemoglobin tetramer are distinguished by their color: the two α<scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_alpha_monomers/1'>-monomers</scene> in light-blue and the two β<scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_beta_monomers/1'>-monomers</scene> in light-green. Each α-monomer is a chain of 141 amino acids and each β-monomer is a chain of 146 amino acids. Be careful not to get confused with the context in which we use the label "α", or "alpha": remember that both the α- and the β-monomers contain α-carbons and α-helices. (''THINK'': How many amino acids does it take to build a molecule of hemoglobin?) | In the three-dimensional structure of hemoglobin to the right, you see two <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_light_blue_chains/2'>light-blue chains</scene> and two <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_light_green_chains/1'>light-green chains</scene>. (''Drag the hemoglobin structure with the mouse to rotate it. To zoom, use your scroll-wheel, or drag while holding shift.'') These are the <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_four_monomers/1'>four monomers</scene> of the hemoglobin molecule, and they are shown in a cartoon-style representation where a single curved line connects the α-carbons in the amino acids of each chain and the [[secondary structure]] α-helices are shown as simplified cartoon helices. Because hemoglobin is composed of four monomers, it is called a <scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_tetramer/2'>tetramer</scene>. The two types of monomers that make up the hemoglobin tetramer are distinguished by their color: the two α<scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_alpha_monomers/1'>-monomers</scene> in light-blue and the two β<scene name='User:Jaime_Prilusky/How_do_we_get_the_oxygen_we_breathe/1hho_beta_monomers/1'>-monomers</scene> in light-green. Each α-monomer is a chain of 141 amino acids and each β-monomer is a chain of 146 amino acids. Be careful not to get confused with the context in which we use the label "α", or "alpha": remember that both the α- and the β-monomers contain α-carbons and α-helices. (''THINK'': How many amino acids does it take to build a molecule of hemoglobin?) | ||
This next view shows the <scene name='Hemoglobin/Alpha2beta2/7'>tetramer</scene> in space-fill representation, with the alpha and beta chains coloured differently. | |||
=====Each monomer has a heme group===== | =====Each monomer has a heme group===== | ||
