Title :
Study on the characterization of a potential thermostable β-galactosidase from thermus thermophilus HB27
Author :
Li, Yan ; Yao, Tianran ; Wei, Miao ; Yan, Ming ; Hao, Ning ; Xu, Lin
Author_Institution :
State Key Lab. of Mater.-Oriented Chem. Eng., Nanjing Univ. of Technol., Nanjing, China
Abstract :
A β-galactosidase gene bgal from Thermus thermophilus was cloned and expressed in Escherichia coli. The optimum temperature for this β-galactosidase activity was 70 °C, at which it maintained stable. The optimal pH for enzyme activity is 6.5. The Km value for ONPG was 3.5 mM, while in the presence of cysteine it decreased to 1.4 mM. Cysteine, β-mercaptoethanol, Fe2+ or Mn2+ promoted the enzymatic activity.
Keywords :
biochemistry; enzymes; microorganisms; molecular biophysics; pH; Escherichia coli; Thermus thermophilus HB27; beta-galactosidase activity; beta-galactosidase gene; beta-mercaptoethanol; cysteine; enzyme activity pH; iron dication; manganese dication; pH 6.5; temperature 70 degC; thermostable beta-galactosidase; Biotechnology; Dairy products; Kinetic theory; Proteins; Substrates; β-galactosidase; Thermus thermophilus; lactose;
Conference_Titel :
Biomedical Engineering and Informatics (BMEI), 2010 3rd International Conference on
Conference_Location :
Yantai
Print_ISBN :
978-1-4244-6495-1
DOI :
10.1109/BMEI.2010.5639979
