The gut-associated Klebsiella sp. of the apple snail produces multiple polysaccharide degrading enzymes

Abstract

Pila globosa, an edible variety of apple snail is a common inhabitant of lentic ecosystem and feeds on plant detritus. The tissue extract of gastrointestinal tract from Pila globosa demonstrated the presence of carboxymethyl cellulase, xylanase, alginate lyase and pectinase activity. Culture-dependent method was used to isolate carboxymethyl cellulose (CMC) degrading bacteria from the gastrointestinal tract of apple snail. Morphologically identical colonies were obtained on M9 gelrite plates containing CMC as carbon source. One such bacterial isolate was purified by streaking and designated as strain PG-1. Bacterial strain PG-1 degraded CMC, pectin, starch and alginate. The 16S rDNA sequence of strain PG1 was 99% identical to Klebsiella oxytoca. Phylogenetic analysis using maximum likelihood revealed the clustering of strain PG1 with the clade belonging to Klebsiella oxytoca type strain.