Sandbox Reserved 1625: Difference between revisions
From Proteopedia
Jump to navigationJump to search
Emily Neal (talk | contribs) No edit summary |
Emily Neal (talk | contribs) No edit summary |
||
| Line 3: | Line 3: | ||
<StructureSection load='6rx4' size='350' frame='true' side='right' caption='Cartoon representation of E. coli cytochrome bd-1 oxidase designed from [https://www.rcsb.org/structure/6RX4 PDB: 6RX4]. Blue= CydA; green= CydB; yellow= CydX; pink= CydS; gray = hemes and UQ-8.' scene='83/832931/Full/3'> | <StructureSection load='6rx4' size='350' frame='true' side='right' caption='Cartoon representation of E. coli cytochrome bd-1 oxidase designed from [https://www.rcsb.org/structure/6RX4 PDB: 6RX4]. Blue= CydA; green= CydB; yellow= CydX; pink= CydS; gray = hemes and UQ-8.' scene='83/832931/Full/3'> | ||
==Introduction== | ==Introduction== | ||
<scene name='83/832931/Full/4'>Cytochrome bd oxidase</scene> is a type of quinol-dependent transmembrane (Fig. 1) terminal [https://en.wikipedia.org/wiki/Oxidase oxidase] found exclusively in prokaryotes.<ref name="Safarian">PMID: 27126043</ref> With a very high oxygen affinity, bd oxidases play a vital role in the https://en.wikipedia.org/wiki/Oxidative_phosphorylation oxidative phosphorylation] pathway in both gram-positive and gram-negative bacteria. Cytochrome ''bd'' oxidase's responsibility in the oxidative phosphorylation pathway also allows it to act as a key survival factor in the bacterial stress response against antibacterial drugs <ref name="Safarian">PMID: 31604309</ref>, hypoxia, cyanide, nitric oxide, and H<sub>2</sub>O<sub>2</sub><ref name="Harikishore">PMID: 31939065</ref>. Given this knowledge, ''bd'' oxidases have become an area of scientific research worth pursuing as they could serve as an ideal target for antimicrobial drug development. <ref name="Boot">PMID: 28878275</ref> | <scene name='83/832931/Full/4'>Cytochrome bd oxidase</scene> is a type of quinol-dependent transmembrane (Fig. 1) terminal [https://en.wikipedia.org/wiki/Oxidase oxidase] found exclusively in prokaryotes.<ref name="Safarian">PMID: 27126043</ref> With a very high oxygen affinity, bd oxidases play a vital role in the [https://en.wikipedia.org/wiki/Oxidative_phosphorylation oxidative phosphorylation] pathway in both gram-positive and gram-negative bacteria. Cytochrome ''bd'' oxidase's responsibility in the oxidative phosphorylation pathway also allows it to act as a key survival factor in the bacterial stress response against antibacterial drugs <ref name="Safarian">PMID: 31604309</ref>, hypoxia, cyanide, nitric oxide, and H<sub>2</sub>O<sub>2</sub><ref name="Harikishore">PMID: 31939065</ref>. Given this knowledge, ''bd'' oxidases have become an area of scientific research worth pursuing as they could serve as an ideal target for antimicrobial drug development. <ref name="Boot">PMID: 28878275</ref> | ||
[[Image:Pp_and_cp_of_oxdiase.png|550 px|center|thumb|''Figure 1''. Cartoon model of cytochrome bd-oxidase in ''E. coli''. Dashed lines represent borders of cytoplasmic and periplasmic regions. A bound quinol between transmembrane helices 6 and 7 undergoes oxidation and releases protons into the periplasmic space, generating a proton gradient. Protons and oxygen atoms from the cytoplasmic side enter cytochrome ''bd'' oxidase through specific channels. Oxygen is reduced to water, which is released into the cytoplasmic space. Blue = CydA; green = CydB; yellow = CydX; pink = CydS. [[https://www.rcsb.org/structure/6RX4 PDB: 6RX4]]]] | [[Image:Pp_and_cp_of_oxdiase.png|550 px|center|thumb|''Figure 1''. Cartoon model of cytochrome bd-oxidase in ''E. coli''. Dashed lines represent borders of cytoplasmic and periplasmic regions. A bound quinol between transmembrane helices 6 and 7 undergoes oxidation and releases protons into the periplasmic space, generating a proton gradient. Protons and oxygen atoms from the cytoplasmic side enter cytochrome ''bd'' oxidase through specific channels. Oxygen is reduced to water, which is released into the cytoplasmic space. Blue = CydA; green = CydB; yellow = CydX; pink = CydS. [[https://www.rcsb.org/structure/6RX4 PDB: 6RX4]]]] | ||
The overall mechanism of ''bd'' oxidases involves an exergonic reduction reaction of molecular oxygen into water (Fig. 2). During this reaction, a proton gradient is generated in order to assist in the conservation of energy. <ref name="Belevich">PMID: 17690093</ref> Unlike other terminal oxidases, bd oxidases do not use a proton pump. Instead, bd oxidases use a form of vectorial chemistry that releases protons from the quinol oxidation into the positive, periplasmic side of the membrane. Protons that are required for the water formation are then consumed from the negative, cytoplasmic side of the membrane, thus creating the previously mentioned proton gradient. | The overall mechanism of ''bd'' oxidases involves an exergonic reduction reaction of molecular oxygen into water (Fig. 2). During this reaction, a proton gradient is generated in order to assist in the conservation of energy. <ref name="Belevich">PMID: 17690093</ref> Unlike other terminal oxidases, bd oxidases do not use a proton pump. Instead, bd oxidases use a form of vectorial chemistry that releases protons from the quinol oxidation into the positive, periplasmic side of the membrane. Protons that are required for the water formation are then consumed from the negative, cytoplasmic side of the membrane, thus creating the previously mentioned proton gradient. | ||
