4P02: Structure Of Bacterial Cellulose Synthase With Cyclic-di-gmp Bound

Citation:
Abstract
The bacterial signaling molecule cyclic di-GMP (c-di-GMP) stimulates the synthesis of bacterial cellulose, which is frequently found in biofilms. Bacterial cellulose is synthesized and translocated across the inner membrane by a complex of cellulose synthase BcsA and BcsB subunits. Here we present crystal structures of the c-di-GMP-activated BcsA-BcsB complex. The structures reveal that c-di-GMP releases an autoinhibited state of the enzyme by breaking a salt bridge that otherwise tethers a conserved gating loop that controls access to and substrate coordination at the active site. Disrupting the salt bridge by mutagenesis generates a constitutively active cellulose synthase. Additionally, the c-di-GMP-activated BcsA-BcsB complex contains a nascent cellulose polymer whose terminal glucose unit rests at a new location above BcsA's active site and is positioned for catalysis. Our mechanistic insights indicate how c-di-GMP allosterically modulates enzymatic functions.
PDB ID: 4P02Download
MMDB ID: 119073
PDB Deposition Date: 2014/2/20
Updated in MMDB: 2017/10
Experimental Method:
x-ray diffraction
Resolution: 2.65  Å
Source Organism:
Similar Structures:
Biological Unit for 4P02: trimeric; determined by software (PISA)
Molecular Components in 4P02
Label Count Molecule
Proteins (3 molecules)
1
Cellulose Synthase Subunit a
Molecule annotation
1
Cellulose Synthase Subunit B
Molecule annotation
1
Unidentified Peptide
Molecule annotation
Chemicals (25 molecules)
1
17
2
2
3
4
4
1
5
1
* Click molecule labels to explore molecular sequence information.

Citing MMDB
.