Release of the enzyme chitobiase by the copepod Temora longicornis:characteristics and potential tool for estimating crustacean biomass production in the sea
| Autor: | Wim C. M. Klein Breteler, Swier S. Oosterhuis, Martien A. Baars |
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| Rok vydání: | 2000 |
| Předmět: | |
| Zdroj: | Marine Ecology Progress Series. 196:195-206 |
| ISSN: | 1616-1599 0171-8630 |
| Popis: | The chitinolytic enzyme chitobiase (N-acetyl-β-D-glucosaminidase), which is expressed during the pre-moult phase of crustaceans, is released into the ambient water after shedding of the exuvium. We examined the potential use of chitobiase activity in water samples as a measure of secondary production of crustaceans. Chitobiase activity, expressed on the substrate 4-methylumbelliferyl-N-acetyl-β-D-glucosaminide (MUFNAG), was measured in experiments with the marine copepod Temora longicornis, with focus on the dissolved ('free', 100 pmol l -1 , The usefulness of free chitobiase as a natural tracer of secondary production was tested in a culture vessel of T. longicornis. The rate of chitobiase release was derived from the chitobiase activity in the ambient culture water over time and the rate of decay in water samples devoid of copepods. From the relation between release of chitobiase and increase of body weight of moulting copepodites, the total daily biomass increase in the culture vessel was calculated. These estimates compared well with classical monitoring of biomass changes. If this relation found in T. longicornis is representative of marine crustaceans in general, tracking of free chitobiase in water samples could be a biochemical tool for estimating in situ secondary production in natural waters. |
| Databáze: | OpenAIRE |
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