title: Thermostable, haloalkaline cellulase from Bacillus halodurans CAS 1 by conversion of lignocellulosic wastes.
abstract: An extracellular thermostable, haloalkaline cellulase by bioconversion of lignocellulosic wastes from Bacillus halodurans CAS 1 was purified to homogeneity with recovery of 12.54% and purity fold 7.96 with the molecular weight of 44 kDa. The optimum temperature, pH and NaCl for enzyme activity was determined as 60°C, 9.0 and 30% and it retained 80% of activity even at 80°C, 12 and 35% respectively. The activity was greatly inhibited by EDTA, indicating that it was a metalloenzyme and significant inhibition by PMSF revealed that serine residue was essential for catalytic activity. The purified cellulase hydrolyzed CMC, cellobiose and xylan, but not avicel, cellulose and PNPG. Furthermore, the cellulase was highly stable in the presence of detergents and organic solvents such as acetone, n-hexane and acetonitrile. Thus, the purified cellulase from B. halodurans utilizing lignocellulosic biomass could be greatly useful to develop industrial processes.
authors.affiliation: Department of Chemistry, University of Puerto Rico at Cayey, 205, Antonio R. Barcelo, Cayey, PR. annabact@gmail.com
authors.forename: Neelamegam
authors.initials: N
authors.lastname: Annamalai
authors.forename: Mayavan Veeramuthu
authors.initials: MV
authors.lastname: Rajeswari
authors.forename: Sivaramasamy
authors.initials: S
authors.lastname: Elayaraja
authors.forename: Thangavel
authors.initials: T
authors.lastname: Balasubramanian
mesh_terms: D001407:Bacillus / Q000201:enzymology* / Q000254:growth & development; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D002480:Cellulase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D002852:Chromatography, Ion Exchange; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D012275:Oryza / Q000737:chemistry; D010802:Phylogeny; D012965:Sodium Chloride / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013379:Substrate Specificity; D013696:Temperature; D014908:Triticum / Q000737:chemistry; D014866:Waste Products
chemical_list: D001426:Bacterial Proteins; D012997:Solvents; D014866:Waste Products; C036909:lignocellulose; D012965:Sodium Chloride; D008031:Lignin; D002480:Cellulase