Table 4.
Chitinase and β-N-acetyl-hexosaminidase enzyme activities in natural habitats.
| Enzyme activities | System | Method | References |
|---|---|---|---|
| 5.4 × 10−5 – 3.1 × 102 nmol d−1 ml−1 | Freshwater | 1MUF-NAG, in situ T, 100 μM | Vrba et al., 1992 |
| 1.3 × 10−5 – 1.3 × 10−4 nmol d−1 ml−1 | Freshwater | MUF-NAG, in situ T, 50 μ M | Beier et al., 2012 |
| *2.8 × 102 – 3.4 × 102 nmol d−1 g−1 (wet) | Wetland sediment | 2pNP-NAG, 25°C, 5 mM | Jackson and Vallaire, 2009 |
| *4.2 × 10−1 – 1.4 × 102 nmol d−1 ml−1 (wet) | Wetland sediment | MUF-NAG, respective annual mean T, 400 μ M | Kang et al., 2005 |
| *1.7 × 100 – 9.2 × 100 μg d−1 g−1 (dry) | Saltmarsh sediment | pNP-NAG, 30°C, 5 mM | Duarte et al., 2008 |
| *2.4 × 103 – 7.1 × 103 nmol d−1 g−1 (dry) | Soil | pNP-NAG, 25°C, 2 mM | Rietl and Jackson, 2012 |
| Not detectable | Freshwater | 3MUF-DC, 4°C, 50 μM | Köllner et al., 2012 |
| Up to 5.4 × 101 nmol d−1 ml−1 | Freshwater | MUF-DC, in situ T, 50 μ M | Beier et al., 2012 |
| 4.2 × 10−3 – 2.1 × 10−1 nmol d−1 g−1 (dry) | Freshwater sediment | MUF-DC, 4°C, 50 μ M | Köllner et al., 2012 |
| 2.5 × 101 – 7.5 × 103 nmol d−1 g−1 (dry) | Soil | MUF-DC, 37°C, 60 μ M | Ueno et al., 1991 |
| Up to 5.4 × 103 nmol d−1 g−1 (dry) | Soil | 4MUF-TC, 37°C, 25 μ M | Ueno et al., 1991 |
| *5.4 × 103 – 6.3 × 100 μg d−1 g−1 (dry) | Brackish sediment | 5DNP, 15°C, 0.5 mg ml−1 | Hillman et al., 1989 |
If possible, values given in different units in the original publications were transformed into a single unit (listed values do not provide a complete overview on all measurements performed but display examples, values from experimental manipulations measured along with controls from natural habitats were excluded from the table).
MUF-NAG: β-N-acetyl-hexosaminidase/chitinase hydrolysis rates estimated based on the fluorogenic substrate analog N-acetyl-b-D-glucosaminide
pNP-NAG: N-acetyl-hexosaminidase/chitinase hydrolysis rates estimated based on the fluorogenic substrate analog pNP-β-N-acetylglucosaminide
MUF-DC: β-N-acetyl-hexosaminidase/chitinase hydrolysis rates estimated based on the fluorogenic substrate analog methylumbelliferyl-diacetyl-chitobioside
MUF-TC: β-N-acetyl-hexosaminidase/chitinase hydrolysis rates estimated based on the fluorogenic substrate analog methylumbelliferyl-diacetyl-chitotrioside
DNP: N-acetyl-hexosaminidase/chitinase hydrolysis rates estimated based on the fluorogenic substrate analog 3,4-dinitrophenyl-tetra-N-acetyl chitotetraoside
Values derived from digitalized figures using the Engauge Digitizer Program (http://digitizer.sourceforge.net/index.php?c=5).