Title
Cellulase activity in the freshwater amphipod Gammarus lacustris
Document Type
Article
Publication Date
6-2000
Keywords
cellulase, Gammarus lacustriscellulose, amphipod, macroinvertebrate, shredder, endoglucanase, cellobiohydrolase, β–glucosidase
Abstract
Deciduous leaves provide a major allochthonous source of energy to stream food webs, particularly in small, shaded headwater streams. To digest cellulose and other structural carbohydrates in plants, invertebrates must use enzymes that degrade these polymers. Our research focused on the digestion of cellulose by the freshwater amphipod Gammarus lacustris. We used a feeding experiment and laboratory enzyme assays to investigate 3 potential sources of cellulase in G. lacustris: 1) tissue-level production of cellulase by G. lacustris, 2) cellulase activity by gut endosymbionts living in G. lacustris, and 3) ingestion of fungal cellulase exoenzymes that remain active after ingestion by G. lacustris. We determined that G. lacustris possessed endoglucanase and β–glucosidase enzymes that are active on soluble cellulose derivatives. We did not detect cellobiohydrolase activity toward crystalline cellulose in G. lacustris. Endoglucanase and β–glucosidase activity appeared to originate from amphipod tissues; in this experiment microbial enzymes did not contribute to cellulase activity. These results are consistent with other studies indicating that many invertebrates produce endoglucanases and β–glucosidases but very few, if any, produce cellobiohydrolase endogenously.
Publication Title
Journal of the North American Benthological Society
Volume
19
Issue
2
First Page
298
Last Page
307
DOI
https://doi.org/10.2307/1468072
Recommended Citation
McGrath, C. C., & Matthews, R. A. (2000). Cellulase activity in the freshwater amphipod Gammarus lacustris. Journal of the North American Benthological Society, 19(2), 298–307. https://doi.org/10.2307/1468072
Type
Text
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author’s written permission.
Language
English
Format
application/pdf