tailieunhanh - Báo cáo khoa học: Enzymatic characterization and molecular modeling of an evolutionarily interesting fungal b-N-acetylhexosaminidase

Fungalb-N-acetylhexosaminidases are inducible extracellular enzymes with many biotechnological applications. The enzyme fromPenicillium oxalicum has unique enzymatic properties despite its close evolutionary relationship with other fungal hexosaminidases. | IFEBS Journal Enzymatic characterization and molecular modeling of an evolutionarily interesting fungal b-N-acetylhexosaminidase Helena RySlava1 AlZbeta Kalendova1 Veronika Doubnerova1 Premysl Skocdopol1 Vinay Kumar1 2 Zdenek Kukacka1 Petr Pompach1 3 Ondrej Vanek1 3 Kristyna Slámová3 Pavla Bojarova3 Natallia Kulik4 Rudiger Ettrich4 Vladimir Kren3 and Karel Bezouska1 3 1 Department of Biochemistry Faculty of Science Charles University Prague Czech Republic 2 Department of TropicalMedicine Schoolof Public Health and TropicalMedicine Tulane University New Orleans LA USA 3 Institute of Microbiology Academy of Sciences of the Czech Republic Prague Czech Republic 4 Department of Structure and Function of Proteins Institute of Nanobiology and StructuralBiology of GCRC Academy of Sciences of the Czech Republic and Faculty of Sciences of the University of South Bohemia Nove Hrady Czech Republic Keywords deglycosylation enzyme kinetics hexosaminidase molecular dynamics molecular modeling Correspondence K. Bezouska Department of Biochemistry Faculty of Science Charles University Prague Czech Republic Fax 420 22195 1283 Tel 420 2 2195 1272 E-mail bezouska@ Received 21 December 2010 revised 29 April 2011 accepted 9 May 2011 doi Fungal b-N-acetylhexosaminidases are inducible extracellular enzymes with many biotechnological applications. The enzyme from Penicillium oxalicum has unique enzymatic properties despite its close evolutionary relationship with other fungal hexosaminidases. It has high GalNAcase activity tolerates substrates with the modified N-acyl group better and has some other unusual catalytic properties. In order to understand these features we performed isolation biochemical and enzymological characterization molecular cloning and molecular modelling. The native enzyme is composed of two catalytic units 65 kDa each and two propeptides 15 kDa each yielding a molecular weight of 160 kDa. Enzyme deglycosylated by .