Semi-rational design of cellobiose dehydrogenase for increased stability in the presence of peroxide

Engineering the Turnover Stability of Cellobiose Dehydrogenase toward Long-Term Bioelectronic Applications

“…In general, our experiments confirmed that the replacement of methionine residues can improve stability against oxidative damage as shown previously, 42,58 but it also appears to be coupled to a loss in structural stability not immediately evident at short time scale, especially when these substitutions are within the hydrophobic core of the protein. It has been shown previously that mutations, especially in the core of a protein, frequently result in a decrease of the thermodynamic stability.…”

“…The wt CDH peptide 297–339 showed the most pronounced methionine oxidation within the first 4 h, which points to an effect of the close proximity of this loop to the active site of CDH . Further, significant oxidation was measured for the peptide fragment 682–694, which contains one methionine (M690), a stability hotspot known for CDH from previous studies . The authors reported increased stability toward externally added H 2 O 2 when replacing M690 by either L or Y for the activity assayed with DCIP.…”

“… 7 Further, significant oxidation was measured for the peptide fragment 682–694, which contains one methionine (M690), a stability hotspot known for CDH from previous studies. 58 The authors reported increased stability toward externally added H 2 O 2 when replacing M690 by either L or Y for the activity assayed with DCIP. However, DCIP is reduced directly at the DH of CDH, and hence its reduction does not involve the interdomain electron transfer, which is essential for the direct electron transfer ability of CDH on electrodes mediated by the cytochrome domain.…”

“…M690L and M690Y were reported as being more stable toward externally added hydrogen peroxide in Phanarochete crysosporium, albeit having assessed the DCIP turnover stability only; 58 showed significant oxidation during turnover in mass spectroscopy ( mM glucose. These data points were analyzed individually per plate, combined for two randomly chosen plates, and also for the full data set of WT clones from all DWPs.…”

Natural microbial polysaccharides as effective factors for modification of the catalytic properties of fungal cellobiose dehydrogenase

“…Application of CDH in all proposed areas requires high stability of the enzyme and, in particular, maintenance of its intact form with a cytochrome domain. A review of previous literature focused on the stabilization of CDH shows only reports of the use of sugars as effective protective substances in the freeze-drying process (Fischer et al 2014 ) and stabilization of the enzyme with genetic engineering techniques (Balaž et al 2019 ). There are no available research regarding the possibilities of the use of naturally produced fungal and bacterial EPSs as protective agents and modulators of CDH catalytic activity.…”