Carbohydrate transporters of the bacterial phosphoenolpyruvate: sugar phosphotransferase system (PTS)

FEBS Letters

Flükiger, Karin¹  Siebold, Christian¹  Beutler, Rudolf¹  Erni, Bernhard¹ 

[1] Departement für Chemie und Biochemie, Universität Bern, CH-3012 Bern, Switzerland

关键词: Bacterial phosphotransferase system;    Cyclic permutation;    Glucose permease;    Intein;    Membrane protein;    Sugar phosphotransferase system;    Escherichia coli;   

DOI  :  10.1016/S0014-5793(01)02705-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The glucose transporter of Escherichia coli couples translocation with phosphorylation of glucose. The IICB^Glc subunit spans the membrane eight times. Split, circularly permuted and cyclized forms of IICB^Glc are described. The split variant was 30 times more active when the two proteins were encoded by a dicistronic mRNA than by two genes. The stability and activity of circularly permuted forms was improved when they were expressed as fusion proteins with alkaline phosphatase. Cyclized IICB^Glc and IIA^Glc were produced in vivo by RecA intein-mediated trans-splicing. Purified, cyclized IIA^Glc and IICB^Glc had 100% and 30% of wild-type glucose phosphotransferase activity, respectively. Cyclized IIA^Glc displayed increased stability against temperature and GuHCl-induced unfolding.

【 授权许可】

Unknown