Packard, Erica
- Department of Soil and Environment, Swedish University of Agricultural Sciences
Abstract
Estimating enzyme activity is a widely applied method for understanding the activity of organisms and their impact on biogeochemical cycles. In forest soils, fungal oxidative enzymes, such as manganese peroxidases, are key regulators of carbon stocks. Here we investigate whether MBTH/DMAB assays, targeting manganese peroxidase activities, are impacted by the degree of fungal cell disruption during extraction from pure culture. Further, we assess whether substrates 2,6-DMP, ABTS, and L-DOPA can distinguish manganese-dependent peroxidase activities under conditions optimized for MBTH/DMAB. Increased mycelial disruption during enzyme extraction increased estimated manganese peroxidase activity, but also the proportion of activity presumed to be from intracellular manganese-independent peroxidases. All substrates could detect peroxidase activities, but their specificity towards manganese peroxidases varied. In particular, ABTS was more readily oxidized by manganese-independent peroxidases. We recommend that extraction methods from soil be adapted to avoid excessive release of internal peroxidases, due to the trade-off between extraction efficiency and assay specificity.
Keywords
2,6-DMP; ABTS; Decomposition; DMAB; Enzyme assay; Extracellular enzymes; L-DOPA; MBTH
Published in
Fungal Ecology
2026, volume: 80, article number: 101492
Publisher: ELSEVIER SCI LTD
SLU Authors
Jörgensen, Karolina
- Department of Soil and Environment, Swedish University of Agricultural Sciences
- Department of Soil and Environment, Swedish University of Agricultural Sciences
UKÄ Subject classification
Soil Science
Publication identifier
- DOI: https://doi.org/10.1016/j.funeco.2025.101492
Permanent link to this page (URI)
https://res.slu.se/id/publ/145692