4D7U

The structure of the catalytic domain of NcLPMO9C from the filamentous fungus Neurospora crassa

Summary for 4D7U

• Entry DOI: 10.2210/pdb4d7u/pdb
• Related: 4D7V
• Descriptor: ENDOGLUCANASE II, COPPER (II) ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: oxidoreductase, lytic monooxygenase, hemicellulose active, aa9
• Biological source: NEUROSPORA CRASSA
• Total number of polymer chains: 2
• Total formula weight: 47277.84

Authors

Borisova, A.S.,Isaksen, T.,Mathiesen, G.,Sorlie, M.,Sandgren, M.,Eijsink, V.G.H.,Dimarogona, M. (deposition date: 2014-11-27, release date: 2015-07-22, Last modification date: 2024-10-16)

Primary citation

Borisova, A.S.,Isaksen, T.,Dimarogona, M.,Kognole, A.A.,Mathiesen, G.,Varnai, A.,Rohr, A.K.,Payne, C.,Sorlie, M.,Sandgren, M.,Eijsink, V.G.H.,Sorlie, M.
Structural and Functional Characterization of a Lytic Polysaccharide Monooxygenase with Broad Substrate Specificity
J.Biol.Chem., 290:22955-, 2015

PubMed Abstract: The recently discovered lytic polysaccharide monooxygenases (LPMOs) carry out oxidative cleavage of polysaccharides and are of major importance for efficient processing of biomass. NcLPMO9C from Neurospora crassa acts both on cellulose and on non-cellulose β-glucans, including cellodextrins and xyloglucan. The crystal structure of the catalytic domain of NcLPMO9C revealed an extended, highly polar substrate-binding surface well suited to interact with a variety of sugar substrates. The ability of NcLPMO9C to act on soluble substrates was exploited to study enzyme-substrate interactions. EPR studies demonstrated that the Cu(2+) center environment is altered upon substrate binding, whereas isothermal titration calorimetry studies revealed binding affinities in the low micromolar range for polymeric substrates that are due in part to the presence of a carbohydrate-binding module (CBM1). Importantly, the novel structure of NcLPMO9C enabled a comparative study, revealing that the oxidative regioselectivity of LPMO9s (C1, C4, or both) correlates with distinct structural features of the copper coordination sphere. In strictly C1-oxidizing LPMO9s, access to the solvent-facing axial coordination position is restricted by a conserved tyrosine residue, whereas access to this same position seems unrestricted in C4-oxidizing LPMO9s. LPMO9s known to produce a mixture of C1- and C4-oxidized products show an intermediate situation.

PubMed: 26178376
DOI: 10.1074/JBC.M115.660183

Experimental method

X-RAY DIFFRACTION (1.56 Å)