1yzp
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Substrate-free manganese peroxidase
OverviewOverview
Manganese peroxidase (MnP) is an extracellular heme enzyme that catalyzes, the peroxide-dependent oxidation of Mn(II) to Mn(III). The Mn(III) is, released from the enzyme in complex with oxalate. One heme propionate and, the side chains of Glu35, Glu39, and Asp179 were identified as Mn(II), ligands in the 2.0 A resolution crystal structure. The new 1.45 A crystal, structure of MnP complexed with Mn(II) provides a more accurate view of, the Mn-binding site. New features include possible partial protonation of, Glu39 in the Mn-binding site and glycosylation at Ser336. This is also the, first report of MnP-inhibitor complex structures. At the Mn-binding site, divalent Cd(II) exhibits octahedral, hexacoordinate ligation geometry, similar to that of Mn(II). Cd(II) also binds to a putative second weak, metal-binding site with tetrahedral geometry at the C-terminus of the, protein. Unlike that for Mn(II) and Cd(II), coordination of trivalent, Sm(III) at the Mn-binding site is octacoordinate. Sm(III) was removed from, a MnP-Sm(III) crystal by soaking the crystal in oxalate and then, reintroduced into the binding site. Thus, direct comparisons of, Sm(III)-bound and metal-free structures were made using the same crystal., No ternary complex was observed upon incubation with oxalate. The, reversible binding of Sm(III) may be a useful model for the reversible, binding of Mn(III) to the enzyme, which is too unstable to allow similar, examination.
About this StructureAbout this Structure
1YZP is a Single protein structure of sequence from Phanerochaete chrysosporium with MAN, CA, HEM and GOL as ligands. Active as Manganese peroxidase, with EC number 1.11.1.13 Full crystallographic information is available from OCA.
ReferenceReference
High-resolution crystal structure of manganese peroxidase: substrate and inhibitor complexes., Sundaramoorthy M, Youngs HL, Gold MH, Poulos TL, Biochemistry. 2005 May 3;44(17):6463-70. PMID:15850380
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