| Structural highlights
Function
LP9F_NEUCR Lytic polysaccharide monooxygenase (LPMO) that depolymerizes crystalline and amorphous polysaccharides via the oxidation of scissile alpha- or beta-(1-4)-glycosidic bonds, yielding C1 oxidation products (PubMed:23102010, PubMed:31835532, PubMed:35080911). Catalysis by LPMOs requires the reduction of the active-site copper from Cu(II) to Cu(I) by a reducing agent and H(2)O(2) or O(2) as a cosubstrate (By similarity).[UniProtKB:Q7SHI8][1] [2] [3]
Publication Abstract from PubMed
A new paradigm for cellulose depolymerization by fungi focuses on an oxidative mechanism involving cellobiose dehydrogenases (CDH) and copper-dependent lytic polysaccharide monooxygenases (LPMO); however, mechanistic studies have been hampered by the lack of structural information regarding CDH. CDH contains a haem-binding cytochrome (CYT) connected via a flexible linker to a flavin-dependent dehydrogenase (DH). Electrons are generated from cellobiose oxidation catalysed by DH and shuttled via CYT to LPMO. Here we present structural analyses that provide a comprehensive picture of CDH conformers, which govern the electron transfer between redox centres. Using structure-based site-directed mutagenesis, rapid kinetics analysis and molecular docking, we demonstrate that flavin-to-haem interdomain electron transfer (IET) is enabled by a haem propionate group and that rapid IET requires a closed CDH state in which the propionate is tightly enfolded by DH. Following haem reduction, CYT reduces LPMO to initiate oxygen activation at the copper centre and subsequent cellulose depolymerization.
Structural basis for cellobiose dehydrogenase action during oxidative cellulose degradation.,Tan TC, Kracher D, Gandini R, Sygmund C, Kittl R, Haltrich D, Hallberg BM, Ludwig R, Divne C Nat Commun. 2015 Jul 7;6:7542. doi: 10.1038/ncomms8542. PMID:26151670[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Kittl R, Kracher D, Burgstaller D, Haltrich D, Ludwig R. Production of four Neurospora crassa lytic polysaccharide monooxygenases in Pichia pastoris monitored by a fluorimetric assay. Biotechnol Biofuels. 2012 Oct 26;5(1):79. PMID:23102010 doi:10.1186/1754-6834-5-79
- ↑ Laurent CVFP, Sun P, Scheiblbrandner S, Csarman F, Cannazza P, Frommhagen M, van Berkel WJH, Oostenbrink C, Kabel MA, Ludwig R. Influence of Lytic Polysaccharide Monooxygenase Active Site Segments on Activity and Affinity. Int J Mol Sci. 2019 Dec 10;20(24):6219. PMID:31835532 doi:10.3390/ijms20246219
- ↑ Tõlgo M, Hegnar OA, Østby H, Várnai A, Vilaplana F, Eijsink VGH, Olsson L. Comparison of Six Lytic Polysaccharide Monooxygenases from Thermothielavioides terrestris Shows That Functional Variation Underlies the Multiplicity of LPMO Genes in Filamentous Fungi. Appl Environ Microbiol. 2022 Mar 22;88(6):e0009622. PMID:35080911 doi:10.1128/aem.00096-22
- ↑ Tan TC, Kracher D, Gandini R, Sygmund C, Kittl R, Haltrich D, Hallberg BM, Ludwig R, Divne C. Structural basis for cellobiose dehydrogenase action during oxidative cellulose degradation. Nat Commun. 2015 Jul 7;6:7542. doi: 10.1038/ncomms8542. PMID:26151670 doi:http://dx.doi.org/10.1038/ncomms8542
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