Enzymatic Synthesis of Oligosaccharides Containing Gal<i>β</i>→4Gal Disaccharide at the Non-Reducing End Using<i>β</i>-Galactanase from<i>Penicillium citrinum</i>
The transglycosylation reaction was done with a beta-galactanase from Penicillium citrinum. The regioselectivity in the transglycosylation reaction was studied using soy bean arabinogalactan as a donor and mono- or disaccharide derivatives containing beta-galactosyl residue as acceptors. We also synthesized oligosaccharides containing Gal beta 1-->4Gal sequence such as Gal beta 1-->4Gal beta1-->4Glc
Engineering of the <i>Bacillus circulans</i> β-Galactosidase Product Specificity
作者:Huifang Yin、Tjaard Pijning、Xiangfeng Meng、Lubbert Dijkhuizen、Sander S. van Leeuwen
DOI:10.1021/acs.biochem.7b00032
日期:2017.2.7
the multiple biological functions of hMOS, it is important to broaden the variety of GOS structures. In this study, residue R484 near +1 subsite of the C-terminally truncated β-galactosidase from Bacillus circulans (BgaD-D) was subjected to site saturation mutagenesis. Especially the R484S and R484H mutant enzymes displayed significantly altered enzyme specificity, leading to a new type of GOS mixture
微生物β-半乳糖苷酶在工业上被广泛用作从乳糖生产益生元低聚半乳糖(GOS)的生物催化剂。GOS混合物在婴儿配方食品中用作有益的添加剂,以模仿人乳寡糖(hMOS)的益生元作用。GOS混合物的结构多样性明显低于hMOS。由于这种结构复杂性被认为是hMOS多种生物学功能的基础,因此拓宽GOS结构的多样性非常重要。在这项研究中,来自圆形芽孢杆菌C末端截短的β-半乳糖苷酶+1亚位点附近的残基R484(BgaD-D)进行位点饱和诱变。特别是R484S和R484H突变酶显示出显着改变的酶特异性,从而导致一种新型的GOS混合物,其结构和键合类型也发生了改变。这些突变酶产生的GOS混合物含有14种在野生型GOS混合物中不存在的结构。其中10个是全新的结构。这些突变酶产生的GOS包含(β1→3)和(β1→4)键的组合,而野生型酶对(β1→4)键具有明显的偏好。三糖β- d -Gal p-(1→3)-β- d-
Glycosidase-catalysed oligosaccharide synthesis of di-, tri- and tetra-saccharides using the N-acetylhexosaminidase from Aspergillus oryzae and the β-galactosidase from Bacillus circulans
作者:Suddham Singh、Michaela Scigelova、Gabin Vic、David H. G. Crout
DOI:10.1039/p19960001921
日期:——
The N-acetylhexosaminidase from Aspergillusoryzae catalyse transfer of N-acetylglucosaminyl and N-acetylgalactosaminyl residues selectively on to the 6-OH group of N-acetylgalactosamine to give the corresponding (1→6)-linked disaccharides 3 and 6 in 26 and 38% yield, respectively. The disaccharide β-D-GlcpNAc-(1→6)-β-D-GalpNAc 3 thus synthesized acts as acceptor for transfer of a β-D-galactosyl residue
所述Ñ从-acetylhexosaminidase米曲霉的催化转移Ñ -acetylglucosaminyl和Ñ -acetylgalactosaminyl残基选择性地到6-OH基团的Ñ -acetylgalactosamine,得到相应的(1→6) -连接的二糖3和6在26和38%产量分别。二糖β- d -Glc p NAc-(1→6)-β- d -Gal p伏隔3这样合成充当受体用于传送的β- d半乳糖残基由相应的p硝基苯基糖苷到4非还原单元的-OH基团产生卵巢囊液粘蛋白片段β-d -Gal p - (1→4)-β-GLC p NAc-(1→6) - d -Gal p伏隔8产率48%与四糖β-一起d -Gal p - (1→4) - β- D- Gal-(1→4)-β- D- Glc p NAc-(1→6)-D- Gal p NAc 9,产率为7%。以乳糖为受体,在人肠双歧杆菌的生长因子中产生了三糖β-
Structural Elucidation of Enzymatically Synthesized Galacto-oligosaccharides Using Ion-Mobility Spectrometry–Tandem Mass Spectrometry
ingredients derived from lactose in a reactioncatalyzed with β-galactosidases. Enzymatic transgalactosylation results in a mixture of compounds of various degrees of polymerization and types of linkages. Because structure plays an important role in terms of prebiotic activity, it is of crucial importance to provide an insight into the mechanism of transgalactosylation reaction and occurrence of different types