Bacteriology mnemonic

Bacterial toxins that act by ADP-ribosylation

The mnemonic

PECD

What each word stands for

  • PPertussis toxin (blocks Gi)
  • EE. coli heat-labile toxin (activates Gs)
  • CCholera toxin (activates Gs)
  • DDiphtheria toxin (inhibits EF-2)

Why it matters clinically

Links each toxin with the clinical picture: whooping cough, watery diarrhoea, or pharyngeal membrane and myocarditis.

Where it stops being reliable

Omits Pseudomonas exotoxin A, which also inhibits EF-2 by ADP-ribosylation.

Teaching aid, still awaiting independent review. Confirm facts in a standard source.

More mnemonics

Common questions

What is the Bacteriology mnemonic?

PECD. It helps you recall: Bacterial toxins that act by ADP-ribosylation.

What does "P" stand for?

Pertussis toxin (blocks Gi)

What does "E" stand for?

E. coli heat-labile toxin (activates Gs)

What does "C" stand for?

Cholera toxin (activates Gs)

What are all the parts of the PECD mnemonic?

P: Pertussis toxin (blocks Gi); E: E. coli heat-labile toxin (activates Gs); C: Cholera toxin (activates Gs); D: Diphtheria toxin (inhibits EF-2).

Which topic does this mnemonic belong to?

It belongs to Bacteriology in Microbiology.

Where does this mnemonic stop being reliable?

Omits Pseudomonas exotoxin A, which also inhibits EF-2 by ADP-ribosylation.

How is this useful clinically?

Links each toxin with the clinical picture: whooping cough, watery diarrhoea, or pharyngeal membrane and myocarditis.

How do I make this mnemonic stick?

Say it aloud, write it from memory tomorrow, then again in a week. Then test yourself on a Microbiology question about Bacteriology.

Is this a standard mnemonic?

It is a teaching aid written or adapted by our team. Some resemble ones students share informally. Check any fact that matters in a standard source.