Table 2. Extracellular enzymes analyzed, substrate analogs used to determine their potential activities and biogeochemical function of the enzymes according to Sinsabaugh et al. (2008).
| Enzyme | Substrate analog | Function |
|---|---|---|
| Carbon-acquiring enzymes | ||
| β-Glucosidase | 4-MUB-β--glucopyranoside | Cellulose degradation |
| Cellobiosidase | 4-MUB-β-cellobioside | Cellulose degradation |
| β-Xylosidase | 4-MUB-β--xylopyranoide | Hemicellulose degradation |
| Nitrogen-acquiring enzymes | ||
| Chitinase | 4-MUB-N-acetyl-β--glucosaminide | Degradation of β-1,4 glucosamines |
| Leucine-AP | -Leucine-AMC | Peptide degradation |
| Glutamate-AP | -Glutamic acid γ-AMC | Peptide degradation |
| Aspartate-AP | Aspartic acid-AMC | Peptide degradation |
| Phosphorus-acquiring enzyme | ||
| Phosphatase | 4-MUB-phosphate | Phosphomonoester degradation |
| Lignin-degrading enzymes | ||
| Phenol oxidase | 3,4-dihydroxyphenylalanine (-DOPA) | Polyphenol oxidation |
| Peroxidase | 3,4-dihydroxyphenylalanine (-DOPA) with H2O2 | Polyphenol oxidation |
Abbreviations: AMC, 7-amino-4-methylcoumarin; AP, aminopeptidase; MUB, 4-methylumbelliferone.