Structural basis for activation of a diguanylate cyclase required for bacterial predation in Bdellovibrio

DOI: 10.1038/s41467-019-12051-6

Authors: Richard W. Meek (University of Birmingham) , Ian T. Cadby (University of Birmingham) , Patrick J. Moynihan (University of Birmingham) , Andrew K. Lovering (University of Birmingham)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 10

State: Published (Approved)
Published: September 2019
Diamond Proposal Number(s): 10369 , 14692

Abstract: The bacterial second messenger cyclic-di-GMP is a widespread, prominent effector of lifestyle change. An example of this occurs in the predatory bacterium Bdellovibrio bacteriovorus, which cycles between free-living and intraperiplasmic phases after entering (and killing) another bacterium. The initiation of prey invasion is governed by DgcB (GGDEF enzyme) that produces cyclic-di-GMP in response to an unknown stimulus. Here, we report the structure of DgcB, and demonstrate that the GGDEF and sensory forkhead-associated (FHA) domains form an asymmetric dimer. Our structures indicate that the FHA domain is a consensus phosphopeptide sensor, and that the ligand for activation is surprisingly derived from the N-terminal region of DgcB itself. We confirm this hypothesis by determining the structure of a FHA:phosphopeptide complex, from which we design a constitutively-active mutant (confirmed via enzyme assays). Our results provide an understanding of the stimulus driving DgcB-mediated prey invasion and detail a unique mechanism of GGDEF enzyme regulation.

Journal Keywords: Biochemistry; X-ray crystallography

Diamond Keywords: Bacteria; Enzymes

Subject Areas: Biology and Bio-materials


Instruments: I03-Macromolecular Crystallography , I04-1-Macromolecular Crystallography (fixed wavelength) , I04-Macromolecular Crystallography

Added On: 02/10/2019 15:46

Documents:
s41467-019-12051-6.pdf

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)