Transferase Activity of Lactobacillal and Bifidobacterial β-Galactosidases with Various Sugars as Galactosyl Acceptors
详细信息 查看全文
- 作者：Sheryl Lozel Arreola ; Montira Intanon ; Pairote Wongputtisin ; Paul Kosma ; Dietmar Haltrich ; Thu-Ha Nguyen
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2016
- 出版时间：March 30, 2016
- 年：2016
- 卷：64
- 期：12
- 页码：2604-2611
- 全文大小：377K
- ISSN：1520-5118
文摘
The β-galactosidases from Lactobacillus reuteri L103 (Lreuβgal), Lactobacillus delbrueckii subsp. bulgaricus DSM 20081 (Lbulβgal), and Bifidobacterium breve DSM 20281 (Bbreβgal-I and Bbreβgal-II) were investigated in detail with respect to their propensity to transfer galactosyl moieties onto lactose, its hydrolysis products d-glucose and d-galactose, and certain sugar acceptors such as N-acetyl-d-glucosamine (GlcNAc), N-acetyl-d-galactosamine (GalNAc), and l-fucose (Fuc) under defined, initial velocity conditions. The rate constants or partitioning ratios (kNu/kwater) determined for these different acceptors (termed nucleophiles, Nu) were used as a measure for the ability of a certain substance to act as a galactosyl acceptor of these β-galactosidases. When using Lbulβgal or Bbreβgal-II, the galactosyl transfer to GlcNAc was 6 and 10 times higher than that to lactose, respectively. With lactose and GlcNAc used in equimolar substrate concentrations, Lbulβgal and Bbreβgal-II catalyzed the formation of N-acetyl-allolactosamine with the highest yields of 41 and 24%, respectively, as calculated from the initial GlcNAc concentration.