Methionine oxidation: difference between revisions
Diff·revision 3 → 4·16:00, 7 Dec 2024
Difference between revision 3 and revision 4 of Methionine oxidation. 2 lines changed; the page grew by 246 bytes.
| Revision 3 — 01:43, 18 Nov 2024 PuffRemoverPax (talk) add the figure for the chromatogram and caption its axes 2,072 bytes +656 | Revision 4 — 16:00, 7 Dec 2024 MolarMassMaeve (talk) expand §Chemistry and promoters 2,318 bytes +246 | ||
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| 10 | Oxidation is promoted by dissolved oxygen, by trace transition metals, by peroxide impurities in excipients, and by light. Unlike [[Deamidation|deamidation]], which proceeds spontaneously in clean aqueous solution, oxidation generally requires an oxidant, and controlling the oxidant is therefore an effective control strategy.{{r|usp1503}} | 10 | Oxidation is promoted by dissolved oxygen, by trace transition metals, by peroxide impurities in excipients, and by light. Unlike [[Deamidation|deamidation]], which proceeds spontaneously in clean aqueous solution, oxidation generally requires an oxidant, and controlling the oxidant is therefore an effective control strategy.{{r|usp1503}} |
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| + | 12 | The consequence for activity depends on where the methionine sits. A surface methionine remote from the binding region may be oxidised with little effect; one within the receptor-contact region can substantially reduce potency.{{r|manning2010}} | |
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| 12 | == Chemistry and promoters == | 14 | == Chemistry and promoters == |
| 13 | The sulfur of methionine is readily oxidised by two-electron oxidants such as hydrogen peroxide to the sulfoxide, a reaction that is fast and essentially irreversible under ordinary conditions. Further oxidation to the sulfone requires more forcing conditions and is less commonly observed in practice.{{r|manning2010}} | 15 | The sulfur of methionine is readily oxidised by two-electron oxidants such as hydrogen peroxide to the sulfoxide, a reaction that is fast and essentially irreversible under ordinary conditions. Further oxidation to the sulfone requires more forcing conditions and is less commonly observed in practice.{{r|manning2010}} |