title: Diversity of plant cell wall esterases in thermophilic and thermotolerant fungi.
abstract: Fourteen thermophilic and thermotolerant fungal strains isolated from composting soils produced plant cell wall-acting esterases in a medium containing corn cobs and oat spelt xylan. The concentrated and dialyzed protein extracts of these fungi were fractionated using isoelectric-focusing, gels sliced and eluted protein in each slice was assayed for esterase activity against p-nitrophenyl acetate. A total of 84 esterases detected on the basis of pI were found to show distinct preferential substrate specificities towards p-nitrophenyl acetate, p-nitrophenyl ferulate and p-nitrophenyl butyrate, and were putatively classified as acetyl esterases and esterases types I and II. None of the esterases were active against p-nitrophenyl myristate. In addition, these esterases were characterized as acid, neutral or alkaline active.
authors.affiliation: Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, India.
authors.forename: Sonia K
authors.initials: SK
authors.lastname: Ghatora
authors.forename: Bhupinder S
authors.initials: BS
authors.lastname: Chadha
authors.forename: Harvinder S
authors.initials: HS
authors.lastname: Saini
authors.forename: Mahalingeshwara K
authors.initials: MK
authors.lastname: Bhat
authors.forename: Craig B
authors.initials: CB
authors.lastname: Faulds
mesh_terms: D002473:Cell Wall / Q000378:metabolism; D005591:Chemical Fractionation; D004950:Esterases / Q000145:classification* / Q000378:metabolism; D005656:Fungal Proteins / Q000145:classification* / Q000378:metabolism; D005658:Fungi / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing / Q000379:methods; D020033:Protein Isoforms / Q000145:classification / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D005656:Fungal Proteins; D020033:Protein Isoforms; D004950:Esterases