Cellulase Activity of Symbiotic Bacteria from Snails, Achatina fulica

Cellulase is the key enzyme in the use of cellulose-based biomaterials. Because of its structure, cellulose is difficult to be degraded by enzymes. In order to utilize cellulose-based biomaterials efficiently, evolutionary wisdom of how to use enzymes accurately and harmoniously in a biological system is needed, such as the cellulose digestive system in animals. In this study, the symbiotic bacteria from snails, Achatina fulica, were identified and their cellulase activity was evaluated. The 16S rRNA sequence analysis of 100 aerobic bacteria showed that they belonged to 9 genus and almost half of the bacteria were Lactococcus spp. Among 100 identified strains, only two Aeromonas sp. strains showed cellulase activity. Aeromonas sp. KMBS020 had both endo-<TEX>β</TEX>-glucanase and <TEX>β</TEX>-glucosidase activities but Aeromonas sp. KMBS018 had <TEX>β</TEX>-glucosidase activity only. None of the 100 bacterial colonies had any cellobiohydrolase activity.