Draft genome sequence of Parvularcula flava strain NH6-79, revealing its role as a cellulolytic enzymes producer.

To date, the genus Parvularcula consists of 6 species and no potential application of this genus was reported. Current study presents the genome sequence of Parvularcula flava strain NH6-79 and its cellulolytic enzyme analysis. The assembled draft genome of strain NH6-79 consists of 9 contigs and 7 scaffolds with 3.68 Mbp in size and GC content of 59.87%. From a total of 3,465 genes predicted, 96 of them are annotated as glycoside hydrolases (GHs). Within these GHs, 20 encoded genes are related to cellulosic biomass degradation, including 12 endoglucanases (5 GH10, 4 GH5, and 3 GH51), 2 exoglucanases (GH9) and 6 β-glucosidases (GH3). In addition, highest relative enzyme activities (endoglucanase, exoglucanase, and β-glucosidase) were observed at 27th hour when the strain was cultured in the carboxymethyl cellulose/Avicel-containing medium for 45 h. The combination of genome analysis with experimental studies indicated the ability of strain NH6-79 to produce extracellular endoglucanase, exoglucanase, and β-glucosidase. These findings suggest the potential of Parvularcula flava strain NH6-79 in cellulose-containing biomass degradation and that the strain could be used in cellulosic biorefining process.