Sandbox Reserved 335: Difference between revisions
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== Introduction == | == Introduction == | ||
=== ''Rhodothermus marinus'' === | === ''Rhodothermus marinus'' === | ||
''Rhodothermus marinus'' is a Gram-negative bacterium in the class Sphingobacteria, in phylum Bacteroidetes. These bacteria are thermophilic, obligate aerobes that have been previously isolated from shallow-water submarine hot springs located in Iceland.<ref name="bacteria">Alfredsson GA, Kristjansson JK, Hjörleifsdottir S, Stetter, KO. Rhodothermus marinus, gen. nov., sp. nov., a thermophilic, halophilic bacterium from submarine hot springs in Iceland. J Gen Microbiol. 1988 Feb;134(2):299-306.</ref> | |||
== Function == | == Function == | ||
Monoheme cytochromes ''c'' are involved in electron transport chains in both prokaryotes and eukaryotic mitochondria.<ref name=main /> They mediate the transfer of electrons mainly from the ''bc''<sub>1</sub> complexes, or their analogs, in the electron transport chain to heme-copper oxygen reductases (HCOs) during oxidative phosphorylation. | Monoheme cytochromes ''c'' are involved in electron transport chains in both prokaryotes and eukaryotic mitochondria.<ref name=main /> They mediate the transfer of electrons mainly from the ''bc''<sub>1</sub> complexes, or their analogs, in the electron transport chain to heme-copper oxygen reductases (HCOs) during oxidative phosphorylation. Heme ''c'' containing domains are often found fused to other protein domains such as these HCOs, including the ''caa''<sub>3</sub> oxygen reductases<ref name=main /><ref>PMID:14691678</ref>; these enzymes are membrane-bound and catalyze the reduction of O<sub>2</sub> to water.<ref>PMID:11334784</ref> In addition to being involved in the electron transport systems in oxidative phosphorylation, monoheme cyt''c'' has also been seen to participate in the electron transport chain of photosynthesis.<ref name=main /> | ||
== Structure == | == Structure == | ||
All members in the C-type cytochrome superfamily contain a heme prosthetic group that is covalently attached to the protein via two thioether bonds to cysteine residues.<ref name=main>PMID:18855424</ref> Most cytochromes ''c'' occur in a CXXCH motif, where a histidine residue is one of the two axial ligands of the heme iron. The other axial position may be left vacant or be occupied mostly by histidine or methionine residues, but can sometimes be occupied by cysteine or leucine residues.<ref name=main /> | All members in the C-type cytochrome superfamily contain a heme prosthetic group that is covalently attached to the protein via two thioether bonds to cysteine residues.<ref name=main>PMID:18855424</ref> Most cytochromes ''c'' occur in a CXXCH motif, where a histidine residue is one of the two axial ligands of the heme iron. The other axial position may be left vacant or be occupied mostly by histidine or methionine residues, but can sometimes be occupied by cysteine or leucine residues.<ref name=main /> | ||
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=== ''Rhodothermus marinus'' monoheme cytochrome ''c'' === | === ''Rhodothermus marinus'' monoheme cytochrome ''c'' === | ||
The typical monoheme cyt ''c'' fold is formed by helices <scene name='Sandbox_Reserved_335/Helices/1'>A, C, and E</scene>. In ''Rm''cyt''c'', there are seven α-helices, | |||
The typical monoheme cyt ''c'' fold is formed by helices <scene name='Sandbox_Reserved_335/Helices/1'>A, C, and E</scene>. | |||
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== References == | == References == | ||
<references/> | <references/> | ||
