title: Glucoamylases from Penicillium verruculosum and Myceliophthora thermophila: analysis of differences in activity against polymeric substrates based on 3D model structures of the intact enzymes.
abstract: Two glucoamylases, a recombinant enzyme from Penicillium verruculosum (PvGla) heterologously expressed in Penicillium canescens RN3-11-7 (niaD-) strain and a native glucoamylase from Myceliophthora thermophila (MtGla), were purified and their properties were studied. MtGla displayed 2-5-fold higher specific activities against soluble starch, amylose and amylopectin than PvGla. MtGla also provided higher glucose yields in extended hydrolysis of the polymeric substrates. Analysis of 3D model structures of the intact PvGla and MtGla, which were built using the 2vn7.pdb crystal structure of the intact Trichoderma reesei glucoamylase (TrGla) as a template, showed that the reason for lower hydrolytic performance of PvGla in comparison to MtGla may be less strong interactions between the enzyme domains as well as a longer (by 17 residues) linker in the first enzyme.
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia.
authors.forename: Pavel V
authors.initials: PV
authors.lastname: Volkov
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia. Electronic address: amrojkova@mail.ru.
authors.forename: Aleksandra M
authors.initials: AM
authors.lastname: Rozhkova
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia; Department of Chemistry, M.V. Lomonosov Moscow State University, Vorobyovy Gory 1/11, Moscow 119991, Russia.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Gusakov
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia; Department of Chemistry, M.V. Lomonosov Moscow State University, Vorobyovy Gory 1/11, Moscow 119991, Russia.
authors.forename: Ivan N
authors.initials: IN
authors.lastname: Zorov
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia; Department of Chemistry, M.V. Lomonosov Moscow State University, Vorobyovy Gory 1/11, Moscow 119991, Russia.
authors.forename: Arkady P
authors.initials: AP
authors.lastname: Sinitsyn
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000201:enzymology*; D001704:Biopolymers / Q000378:metabolism*; D005087:Glucan 1,4-alpha-Glucosidase / Q000737:chemistry* / Q000378:metabolism*; D006868:Hydrolysis; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010407:Penicillium / Q000201:enzymology*; D011485:Protein Binding; D011487:Protein Conformation; D013045:Species Specificity; D013379:Substrate Specificity
chemical_list: D001704:Biopolymers; D005087:Glucan 1,4-alpha-Glucosidase
keywords: Glucoamylase; Hydrolysis; Modeling; Myceliophthora thermophila; Penicillium verruculosum