Some characteristics and isolation of novel thermostable β-galactosidase from Thermus oshimai DSM 12092
- 173 Downloads
The β-galactosidases belong to the class of hydrolytic enzymes and have been used as lactose hyrolysis. The enzyme is used in reducing lactose milk production, an outstanding industrial product used by a large lactoseintolerant population. This is the first detailed report of some characteristics of β-galactosidase and the gene encoding β-galactosidase in Thermus oshimai DSM 12092. The growth rate (μ, 1/h), and the doubling time (tD, h) for T. oshimai grown both in shaking flasks and in a bioreactor were determined. The optimal temperature and pH for β-galactosidase were determined as 75°C and 7.4, respectively. This enzyme was thermostable and was retained by more than 70% at 90°C for 3 h. The β-galactosidase from T. oshimai DSM 12092 was more stable in basic pH and Zn2+ was the most effective divalent cation. Also, 2 steps of purification consisting of ammonium sulfate precipitation and gel filtration were employed and purified 32-fold.
Keywordsβ-galactosidase T. oshimai DSM 12092 thermostability galactooligosaccarides synthesis
Unable to display preview. Download preview PDF.
- 4.Grosova Z, Rosenberg M, Rebroš M. Perspectives and applications of immobilised β-galactosidase in food industry — A review. Czech J. Food Sci. 26: 1–14 (2008)Google Scholar
- 11.Koyama Y, Hoshino T, Tomizuka N, Furukawa K. Genetic transformation of the extreme thermophile Thermus thermophilus and of other Thermus spp. J. Bacteriol. 166: 338–340 (1986)Google Scholar
- 13.Vian A, Carrascosa AV, García JL, Cortés E. Structure of the β-galactosidase gene from Thermus sp. strain T2: Expression in Escherichia coli and purification in a single step of an active fusion protein. Appl. Environ. Microb. 64: 2187–2191 (1998)Google Scholar
- 14.Nam ES, Choi JW, Lim JH, Hwang SK, Jung HJ, Kang SK, Cho KK, Choi YJ, Ahn JK. β-Galactosidase gene of Thermus thermophilus KNOUC112 isolated from hot springs of a volcanic area in New Zealand: Identification of the bacteria, cloning, and expression of the gene in Escherichia coli. Asian Austral. J. Anim. Sci. 17: 1591–1598 (2004)Google Scholar
- 15.Fridjonsson O, Watzlawick H, Gehweiler A, Rohrhirsch T, Mattes R. Cloning of the gene encoding a novel thermostable α-galactosidase from Thermus brockianus ITI360. Appl. Environ. Microb. 65: 3955–3963 (1999)Google Scholar
- 17.Miller JH. Experiments in Molecular Genetics. Cold Spring Harbor Laboratory Press, New York, NY, USA. p. 468 (1972)Google Scholar
- 21.Demirtas MU, Kolhatkar A, Kýlbane JJ. Effect of aeration and agitation on growth rate of Thermus thermophilus in batch mode. J. Biosci. Bioeng. 95: 113–117 (2003)Google Scholar
- 23.Dickson RC, Markin JS. Physiological studies of β-galactosidase induction in Kluyveromyces lactis. J. Bacteriol. 142: 777–785 (1980)Google Scholar
- 29.Koyama Y, Okamoto S, Furukawa K. Cloning of α- and β-galactosidase genes from an extreme thermophile, Thermus strain T2, and their expression in Thermus thermophilus HB27. Appl. Microbiol. Biot. 56: 2251–2254 (1990)Google Scholar