Aquacobalamin

Aquacobalamin is one of the major forms of vitamin B12 isolated from mammalian cells. Aquacobalamin accelerates the oxidation of azo-dye Orange II (HY-N1442) by HSO5- in aqueous solutions. Aquacobalamin binds hydrogen peroxide reversibly to form a cobalt(III) hydroperoxo adduct with a 0.25 mM dissociation constant[1][2][3].

O[Co+3]1234-;@[N]5=;@C6-;@C(C)=;@C(-;@C(CC(N)=O)(C)-;@C-;@7CCC(N)=O)-;@[N]-;@1=;@C7-;@C=;@C(-;@C(C)(C)-;@C-;@8CCC(N)=O)-;@[N]-;@2=;@C8-;@C(C)=;@C(-;@C(C)(-;@C-;@C-;@C(-;@N-;@C-;@C(C)-;@O-;@P(-;@O-;@C9-;@C(O)-;@C(-;@O-;@C-;@9CO)-;@N%10-;@C=;@[N]-;@4-;@C%11=;@C-;@%10-;@C=;@C(C)-;@C(C)=;@C-;@%11)([O-])=O)=O)-;@C-;@%12CC(N)=O)-;@[N-]-;@3-;@C%12-;@C-;@5(C)-;@C(CC(N)=O)(C)-;@C-;@6CCC(N)=O.[OH-]

[1]Ling Xia, et al. Studies on the formation of glutathionylcobalamin: any free intracellular aquacobalamin is likely to be rapidly and irreversibly converted to glutathionylcobalamin. Inorg Chem. 2004 Oct 18;43(21):6848-57.|[2]Maria Lehene, et al. Adduct of Aquacobalamin with Hydrogen Peroxide. Inorg Chem. 2021 Sep 6;60(17):12681-12684.|[3]Ilia A Dereven'kov, et al. Aquacobalamin Accelerates Orange II Destruction by Peroxymonosulfate via the Transient Formation of Secocorrinoid: A Mechanistic Study. Int J Mol Sci. 2022 Oct 7;23(19):11907.