PDBsum entry 4lpc

Transferase

PDB id: 4lpc

Contents

Protein chains

587 a.a.

Ligands

GLC-GLC ×4

GLC-GLC-GLC

BGC-GLC ×4

BGC-GLC-GLC-GLC-GLC-GLC-GLC

GLC-GLC-GLC-GLC

GOL ×11

BGC

Waters ×842

PDB id:

4lpc

Name:

Transferase

Title:

Crystal structure of e.Coli branching enzyme in complex with maltoheptaose

Structure:

1,4-alpha-glucan branching enzyme glgb. Chain: a, b, c, d. Fragment: unp residues 117-728. Synonym: 1,4-alpha-d-glucan:1,4-alpha-d-glucan 6-glucosyl- transferase, alpha-(1->4)-glucan branching enzyme, glycogen branching enzyme, be. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Gene: glgb, b3432, jw3395. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.39Å R-factor: 0.186 R-free: 0.234

Authors:

L.Feng,J.H.Geiger

Key ref:

L.Feng et al. (2015). Crystal Structures of Escherichia coli Branching Enzyme in Complex with Linear Oligosaccharides. Biochemistry, 54, 6207-6218. PubMed id: 26280198 DOI: 10.1021/acs.biochem.5b00228

Date:

16-Jul-13 Release date: 01-Apr-15

Protein chains

P07762  (GLGB_ECOLI) -  1,4-alpha-glucan branching enzyme GlgB from Escherichia coli (strain K12)

Seq: 728 a.a.

Struc: 587 a.a.

Enzyme reactions

• Enzyme class: E.C.2.4.1.18 - 1,4-alpha-glucan branching enzyme.
• Reaction: Formation of 1,6-glucosidic linkages of glycogen.

DOI no: 10.1021/acs.biochem.5b00228

Biochemistry 54:6207-6218 (2015)

PubMed id: 26280198

Crystal Structures of Escherichia coli Branching Enzyme in Complex with Linear Oligosaccharides.

L.Feng, R.Fawaz, S.Hovde, L.Gilbert, J.Chiou, J.H.Geiger.

ABSTRACT

Branching enzyme is responsible for all branching of glycogen and starch. It is an unusual member of the α-amylase family because it has both α-1,4-amylase activity and α-1,6-transferase activity [Drummond, G. S., et al. (1972) Eur. J. Biochem. 26, 168-176]. It also does not react with shorter glucans, though it will bind much longer substrates and substrate mimics [Binderup, K., et al. (2002) Arch. Biochem. Biophys. 397, 279-285]. In an effort to better understand how branching enzyme interacts with its polymeric substrate, we have determined the structure of Δ112 Escherichia coli branching enzyme bound to maltoheptaose and maltohexaose. Together, these structures define six distinct oligosaccharide binding sites on the surface of E. coli branching enzyme. Most of these binding sites surround the edge of the β-barrel domain and are quite far from the active site. Surprisingly, there is no evidence of oligosaccharide binding in the active site of the enzyme. The closest bound oligosaccharide resides almost 18 Å from the active site. Mutations to conserved residues in binding sites I and VI had a debilitating effect on the activity of the enzyme.