Role of asparagine 1134 in glucosidic bond and transglycosylation specificity of reuteransucrase from Lactobacillus reuteri 121

被引：34

作者：

Kralj, Slavko

Eeuwema, Wieger

Eckhardt, Tom H.

Dijkhuizen, Lubbert

机构：

[1] Univ Groningen, Dept Microbiol, Groningen Biomol Sci & Biotechnol Inst, NL-9751 NN Haren, Netherlands

[2] Univ Groningen, Dept Microbiol, TNO, Ctr Carbohydrate Bioproc, NL-9751 NN Haren, Netherlands

来源：

FEBS JOURNAL | 2006年 / 273卷 / 16期

关键词：

glucansucrase; Lactobacillus reuteri; product specificity; reuteransucrase; site-directed mutagenesis;

D O I：

10.1111/j.1742-4658.2006.05376.x

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 [生物化学与分子生物学]; 081704 [应用化学];

摘要：

Glucansucrases from lactic acid bacteria convert sucrose into various alpha-glucans that differ greatly with respect to the glucosidic bonds present (e.g. dextran, mutan, alternan and reuteran). This study aimed to identify the structural features of the reuteransucrase from Lactobacillus reuteri 121 (GTFA) that determine its reaction specificity. We here report a detailed mutational analysis of a conserved region immediately next to the catalytic Asp1133 (putative transition-state stabilizing) residue in GTFA. The data show that Asn1134 is the main determinant of glucosidic bond product specificity in this reuteransucrase. Furthermore, mutations at this position greatly influenced the hydrolysis/transglycosylation ratio. Changes in this amino acid expands the range of glucan and gluco-oligosaccharide products synthesized from sucrose by mutant GTFA enzymes.

引用

页码：3735 / 3742

页数：8

共 23 条

[1]

Molecular basis of the amylose-like polymer formation catalyzed by Neisseria polysaccharea amylosucrase [J].