BOKU - Universität für Bodenkultur Wien - Forschungsinformationssystem

Logo BOKU-Forschungsportal

Gewählte Publikation:

Courtade, G; Wimmer, R; Rohr, AK; Preims, M; Felice, AKG; Dimarogona, M; Vaaje-Kolstad, G; Sorlie, M; Sandgren, M; Ludwig, R; Eijsink, VGH; Aachmann, FL.
(2016): Interactions of a fungal lytic polysaccharide monooxygenase with beta-glucan substrates and cellobiose dehydrogenase
P NATL ACAD SCI USA. 2016; 113(21): 5922-5927. FullText FullText_BOKU

Abstract:
Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that catalyze oxidative cleavage of glycosidic bonds using molecular oxygen and an external electron donor. We have used NMR and isothermal titration calorimetry (ITC) to study the interactions of a broad-specificity fungal LPMO, NcLPMO9C, with various substrates and with cellobiose dehydrogenase (CDH), a known natural supplier of electrons. The NMR studies revealed interactions with cellohexaose that center around the copper site. NMR studies with xyloglucans, i. e., branched beta-glucans, showed an extended binding surface compared with cellohexaose, whereas ITC experiments showed slightly higher affinity and a different thermodynamic signature of binding. The ITC data also showed that although the copper ion alone hardly contributes to affinity, substrate binding is enhanced for metal-loaded enzymes that are supplied with cyanide, a mimic of O-2(-). Studies with CDH and its isolated heme b cytochrome domain unambiguously showed that the cytochrome domain of CDH interacts with the copper site of the LPMO and that substrate binding precludes interaction with CDH. Apart from providing insights into enzyme-substrate interactions in LPMOs, the present observations shed new light on possible mechanisms for electron supply during LPMO action.
Autor/innen der BOKU Wien:
Felice Alfons Konrad
Ludwig Roland
Preims Marita
BOKU Gendermonitor:


Find related publications in this database (Keywords)
lytic polysaccharide monooxygenase
LPMO
cellulose
xyloglucan
cellobiose dehydrogenase


© BOKU Wien Impressum