Function

Exoenzymes (Exo) are secreted by cells and break large macromolecules outside the cells. The breakdown components can pass through the cell wall. Exo C3 is a Clostridium butulinum toxin which binds NAD, splits it into ADP-ribose and nicotinamide and transfers the ADP-ribose to a protein substrate. Exo S and Exo T are secreted by Pseudomonas aeruginosa and has GTPase-activating activity as well as ADP-ribosyltransferase activity.

Disease

Relevance

Structural highlights

3D structures of exoenzyme

Updated on 22-May-2025

Exoenzyme C3

1g24 – CbExo residues 8-218 – Clostridium butulinum

1uzi, 1r45, 1r4b, 2c89 – CbExo catalytic domain
1gze, 2c8b, 2c8d, 2c8e, 2c8g – CbExo catalytic domain (mutant)
3bw8 - Exo catalytic domain - Clostridium limosum

Exoenzyme C3 complexes

1gzf – CbExo catalytic domain + pyridinium derivative + ADP + NAD

2bov – CbExo + GDP + Ral-A GTPase
2a78 – CbExo catalytic domain + GDP + Ral-A GTPase
2a9k – CbExo catalytic domain+ GDP + Ral-A GTPase + NAD
2c8a – CbExo catalytic domain + nicotinamide
2c8c – CbExo catalytic domain (mutant) + ADP + NAD
2c8f, 2c8h – CbExo catalytic domain (mutant) + NAD

Exoenzyme S

1r4t – PaExo GAP domain – Pseudomonas aeruginosa - NMR

1he1 – PaExo GAP domain + Ras-like protein + GDP
1he9 – PaExo GAP domain + Ras-like protein

Exoenzyme T

4jmf – PaExo residues 28-77 + chaperone


Structure of exoenzyme C3 catalytic domain complex with ADP and NAD (PDB code 2c8c).

Drag the structure with the mouse to rotate

ReferencesReferences

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

Michal Harel, Alexander Berchansky