TY - JOUR
T1 - Functional characterization and crystal structure of thermostable amylase from Thermotoga petrophila, reveals high thermostability and an unusual form of dimerization
AU - Hameed, Uzma
AU - Price, Ian
AU - Ikram-Ul-Haq, null
AU - Ke, Ailong
AU - Wilson, David B
AU - Mirza, Osman
N1 - Copyright © 2017 Elsevier B.V. All rights reserved.
PY - 2017/10
Y1 - 2017/10
N2 - Thermostable α-amylases have many industrial applications and are therefore continuously explored from novel sources. We present the characterization of a novel putative α-amylase gene product (Tp-AmyS) cloned from Thermotoga petrophila. The purified recombinant enzyme is highly thermostable and able to hydrolyze starch into dextrin between 90 and 100°C, with optimum activity at 98°C and pH8.5. The activity increased in the presence of Rb(1+), K(1+) and Ca(2+) ions, whereas other ions inhibited activity. The crystal structure of Tp-AmyS at 1.7Å resolution showed common features of the GH-13 family, however was apparently found to be a dimer. Several residues from one monomer interacted with a docked acarbose, an inhibitor of Tp-AmyS, in the other monomer, suggesting catalytic cooperativity within the dimer. The most striking feature of the dimer was that it resembled the dimerization of salivary amylase from a previous crystal structure, and thus could be a functional feature of some amylases.
AB - Thermostable α-amylases have many industrial applications and are therefore continuously explored from novel sources. We present the characterization of a novel putative α-amylase gene product (Tp-AmyS) cloned from Thermotoga petrophila. The purified recombinant enzyme is highly thermostable and able to hydrolyze starch into dextrin between 90 and 100°C, with optimum activity at 98°C and pH8.5. The activity increased in the presence of Rb(1+), K(1+) and Ca(2+) ions, whereas other ions inhibited activity. The crystal structure of Tp-AmyS at 1.7Å resolution showed common features of the GH-13 family, however was apparently found to be a dimer. Several residues from one monomer interacted with a docked acarbose, an inhibitor of Tp-AmyS, in the other monomer, suggesting catalytic cooperativity within the dimer. The most striking feature of the dimer was that it resembled the dimerization of salivary amylase from a previous crystal structure, and thus could be a functional feature of some amylases.
KW - Journal Article
U2 - 10.1016/j.bbapap.2017.06.015
DO - 10.1016/j.bbapap.2017.06.015
M3 - Journal article
C2 - 28648523
SN - 1570-9639
VL - 1865
SP - 1237
EP - 1245
JO - B B A - Proteins and Proteomics
JF - B B A - Proteins and Proteomics
IS - 10
ER -