title: Affinity precipitation of Aspergillus niger pectinase by microwave-treated alginate.
abstract: Affinity precipitation is a simple, single plate separation process in which the complex of a smart macroaffinity ligand with the target protein (from a crude broth) can be selectively precipitated by application of a suitable stimulus. Alginate is a copolymer of guluronic acid and mannuronic acid residues and precipitates with Ca(2+) ions. It was found to bind to pectinase present in a commercial preparation of Aspergillus niger, Pectinex Ultra-SPL. Microwave pretreatment of alginate at 75 degrees C was found to enhance the selectivity of the affinity precipitation. Using microwave-treated alginate, 83% of the enzyme activity with 20-fold purification could be recovered. SDS-PAGE upon silver staining confirmed the enhanced selectivity of affinity precipitation when microwave-treated alginate was used.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India.
authors.forename: Kalyani
authors.initials: K
authors.lastname: Mondal
authors.forename: Payal
authors.initials: P
authors.lastname: Mehta
authors.forename: Munishwar N
authors.initials: MN
authors.lastname: Gupta
mesh_terms: D000464:Alginates / Q000737:chemistry / Q000378:metabolism*; D001234:Aspergillus niger / Q000201:enzymology*; D002122:Calcium Chloride / Q000737:chemistry; D011232:Chemical Precipitation; D004591:Electrophoresis, Polyacrylamide Gel; D020723:Glucuronic Acid / Q000737:chemistry / Q000378:metabolism*; D006603:Hexuronic Acids / Q000737:chemistry / Q000378:metabolism*; D008872:Microwaves; D011096:Polygalacturonase / Q000302:isolation & purification* / Q000378:metabolism; D011485:Protein Binding; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D011096:Polygalacturonase; D002122:Calcium Chloride