PDBsum entry 2c8c

Transferase

PDB id: 2c8c

Contents

Protein chains

205 a.a. *

Ligands

NAD ×3

ADP

* Residue conservation analysis

PDB id:

2c8c

Name:

Transferase

Title:

Structure of the artt motif q212a mutant c3bot1 exoenzyme (NAD-bound state, crystal form i)

Structure:

Mono-adp-ribosyltransferase c3. Chain: a, b, c, d. Synonym: exoenzyme c3. Engineered: yes. Mutation: yes

Source:

Clostridium botulinum. Organism_taxid: 1491. Expressed in: escherichia coli. Expression_system_taxid: 511693.

Resolution:

2.70Å R-factor: 0.243 R-free: 0.283

Authors:

E.A.Stura,J.Menetrey,G.Flatau,P.Boquet,A.Menez

Key ref:

J.Ménétrey et al. (2008). Structural basis for the NAD-hydrolysis mechanism and the ARTT-loop plasticity of C3 exoenzymes. Protein Sci, 17, 878-886. PubMed id: 18369192

Date:

03-Dec-05 Release date: 27-Feb-07

Protein chains

Q7M0L1  (Q7M0L1_CLOBO) -  Exoenzyme C3 (Fragment) from Clostridium botulinum

Seq: 22 a.a.

Struc: 205 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.2.4.2.- - ?????

Protein Sci 17:878-886 (2008)

PubMed id: 18369192

Structural basis for the NAD-hydrolysis mechanism and the ARTT-loop plasticity of C3 exoenzymes.

J.Ménétrey, G.Flatau, P.Boquet, A.Ménez, E.A.Stura.

ABSTRACT

C3-like exoenzymes are ADP-ribosyltransferases that specifically modify some Rho GTPase proteins, leading to their sequestration in the cytoplasm, and thus inhibiting their regulatory activity on the actin cytoskeleton. This modification process goes through three sequential steps involving NAD-hydrolysis, Rho recognition, and binding, leading to Rho ADP-ribosylation. Independently, three distinct residues within the ARTT loop of the C3 exoenzymes are critical for each of these steps. Supporting the critical role of the ARTT loop, we have shown previously that it adopts a distinct conformation upon NAD binding. Here, we present seven wild-type and ARTT loop-mutant structures of C3 exoenzyme of Clostridium botulinum free and bound to its true substrate, NAD, and to its NAD-hydrolysis product, nicotinamide. Altogether, these structures expand our understanding of the conformational diversity of the C3 exoenzyme, mainly within the ARTT loop.