*4.7. Phenolic Compound Extraction and Quantification*

Gametophores grown in liquid culture were harvested 96 h after treatment, ground in liquid nitrogen and extracted for soluble phenolic content as previously described [17]. The quantitative determination of phenolics was performed using Folin–Ciocalteu reagent with ferulic acid as standard.

## *4.8. Molecular Weight MALDI-TOF/TOF*

The purified peroxidase was analyzed in a MALDI-TOF/TOF instrument as previously described [20]. The search for peptide mass fingerprints and tandem MS spectra was performed in the NCBInr database without taxonomy restriction. Mascot scores for all protein identifications were higher than the accepted threshold for significance (at the *p* < 0.050 level, positive rate measured to be 0.047).

#### *4.9. Sequence Data Analysis*

The presence of signal peptides was predicted using TargetP (http://www.cbs.dtu. dk/services/TargetP/, accessed on 24 November 2020), Bacello (http://gpcr2.biocomp. unibo.it/bacello/index.htm, accessed on 24 November 2020) and TargetLoc (http://abi.inf. unituebingen.de/Services/MultiLoc/index\_html, accessed on 24 November 2020). pI prediction was carried out using Compute pI/MW tool from ExPASy (http://web.expasy.org/ compute\_pi, accessed on 24 November 2020). A search for protein sequences homologies was performed using BLASTP from Redoxibase (http://www.peroxibase.toulouse.inra.fr, accessed on 4 February 2021) and protein alignments were carried out using Clustal Omega (https://www.ebi.ac.uk/Tools/msa/clustalo/, accessed on 4 February 2021). Search for *N*-glycosylation sites was performed using the NetNGlyc tool (http://www.cbs.dtu.dk/ services/NetNGlyc, accessed on 25 November 2020).
