Table 1.
Cyclomodulins and their key features.
| Toxin type | Species | Proteins | Enzymatic activity | Cell cycle phase delay | |
|---|---|---|---|---|---|
| PROTEIN OR PEPTIDES TOXINS | |||||
| Cyclomodulins with enzymatic activities | |||||
| Cycle Inhibiting Factor (CIF) | Cysteine protease | E. coli (EHEC, EPEC) | 2 domains: N-terminal (secretion and translocation) C-terminal (enzymatic) | Deamidase | G1/S G2/M |
| Y. pseudotuberculosis | |||||
| Pseudomonas sp. | |||||
| Enterobacter sp. | |||||
| Serratia sp. | |||||
| Γ-glutamyl transpeptidase (GGT) | Enzyme | H. pylori | 1 protein with 2 chains cleaved by autocatalysis | Gamma-glutamyltransferase | G1/S |
| Cytolethal Distending Toxin (CDT) | Three globular subunits | E. coli H. hepaticus S. enterica serovar Typhimurium | CdtB catalytic subunit CdtA and CdtC cell binding subunits | CdtB subunit: Dnase and phosphatase | G1/S G2/M |
| Shiga toxin (Stx) (Verotoxin) | AB5 toxin | S. dysenteriaeE. Coli (STEC) | stxA enzymatic subunit StxB binding subunit | A subunit: N-glycosidase | S |
| Subtilase AB (SubAB) | AB5 toxin | E. coli (STEC) | SubA enzymatic subunit SubB binding subunit | A subunit: protease | G1/S |
| Anthrax toxin (Edema toxin/Lethal toxin) | Tripartite toxin | B. anthracis | Edema and/or Lethal factor (A enzymatic subunit) Protective Antigen (B binding subunit) | Edema factor : adenylate cyclase Lethal factor: zinc metalloprotease | G1/S |
| Cholera toxin (Ctx) | AB5 toxin Oligomeric complex | V. cholerae | CTA comprises CTA1 and CTA2 domains CTB (B binding subunit) | ADP-ribosyltransferase | G1/S |
| Adenylate Cyclase Toxin (ACT) | AB5 toxin | B. pertussis | S1 enzymatic A subunit S2 to S5 binding B subunits | A subunit: acetyltransferase | G1/S |
| Vacuolating cytotoxin (VacA) | Pore-forming toxin | H. pylori | 3 domains (p33, p55, β-barrel) | Hypothetically | G1/S |
| Cytotoxic Necrotizing Factor 1 (CNF1) | Non canonical AB toxin | E. coli | 3 domains: N-terminal (binding) C-terminal (enzymatic) Central (translocation) | Deaminase | G2/M |
| Cyclomodulins without enzymatic activities | |||||
| Panton–Valentine leukocidin (PVL) | β-pore-forming toxin Bi-component toxin | S. aureus | LukS-PV LukF-PV | No | G0/G1 |
| Phenol soluble modulins (PSMs) | Peptides | S. aureus | PSMα, PSMβ, PSMγ | No | G2/M |
| NON-PROTEINACEOUS CYCLOMODULINS | |||||
| Mycolactone | Macrolide | M. ulcerans | − | No | G0/G1 |