Int J Biochem Mol Biol 2011;2(2):146-154

Original Article
Characterization of some efficient cellulase producing bacteria isolated from paper mill
sludges and organic fertilizers

Miranda L Maki, Michael Broere, Kam Tin Leung, Wensheng Qin

Biorefining Research Initiative, Lakehead University, 955 Oliver Rd, Thunder Bay, Ontario P7B5E1, Canada; Department of Biology, Lakehead
University, 955 Oliver Rd, Thunder Bay, Ontario P7B5E1, Canada.

Received April 1, 2011; accepted April 15, 2011; Epub April 19, 2011; Published April 30, 2011

Abstract: The wide variety of bacteria in the environment permits screening for more efficient cellulases to help overcome current challenges in
biofuel production. This study focuses on the isolation of efficient cellulase producing bacteria found in organic fertilizers and paper mill
sludges which can be considered for use in large scale biorefining. Pure isolate cultures were screened for cellulase activity. Six isolates: S1,
S2, S3, S4, E2, and E4, produced halos greater in diameter than the positive control (Cellulomonas xylanilytica), suggesting high cellulase
activities. A portion of the 16S rDNA genes of cellulase positive isolates were amplified and sequenced, then BLASTed to determine likely
genera. Phylogenetic analysis revealed genera belonging to two major Phyla of Gram positive bacteria: Firmicutes and Actinobacteria. All
isolates were tested for the visible degradation of filter paper; only isolates E2 and E4 (Paenibacillus species) were observed to completely
break down filter paper within 72 and 96 h incubation, respectively, under limited oxygen condition. Thus E2 and E4 were selected for the FP
assay for quantification of total cellulase activities. It was shown that 1% (w/v) CMC could induce total cellulase activities of 1652.2±61.5 and
1456.5±30.7 µM of glucose equivalents for E2 and E4, respectively. CMC could induce cellulase activities 8 and 5.6X greater than FP, therefore
CMC represented a good inducing substrate for cellulase production. The genus Paenibacillus are known to contain some excellent cellulase
producing strains, E2 and E4 displayed superior cellulase activities and represent excellent candidates for further cellulase analysis and
characterization. (IJBMB1104001).

Keywords: Biodegradation, cellulase-producing bacteria, Firmicutes, Actinobacteria

Full Text  PDF  

Address all correspondence to:
Dr. Wensheng Qin
Biorefining Research Initiative
Lakehead University, 955 Oliver Rd
Thunder Bay, Ontario P7B5E1, Canada                                                                                                        
Tel:  (807) 343-8840, Fax:  (807) 346-7796