Which genes does P. gingivalis need to grow?
A near-saturating Tn-seq screen finds ~463 (~22%) P. gingivalis genes putatively essential on blood agar.
Source
Identification of essential genes of the periodontal pathogen Porphyromonas gingivalis
What they did
Authors built a Mariner Tn-seq library in P. gingivalis ATCC 33277 and scored insertion under-representation to call genes required for in vitro survival on blood agar.
What they found
463 genes (22%) are putatively essential; most have essential homologues elsewhere, while ~21% may be species/niche-specific essentials.
The limits
What it doesn't show
Blood-agar essentials ≠ all virulence genes in the host; different selective pressures will reveal other gene sets.
Key terms
- Tn-seq
- Transposon insertion sequencing to find essential/conditioned genes.
- Essential gene
- Gene required for growth under the tested condition.
- Porphyromonas gingivalis
- Oral anaerobic keystone pathogen linked to periodontitis.
- Mariner transposon
- Mobile element inserting primarily at TA dinucleotides.
- Keystone pathogen
- Microbe whose presence disproportionately reshapes community and disease.
Flashcards
Want these cards to stick?
Save the deck to NoteFren and study it with spaced repetition.
Quiz yourself
Putative essential gene count:
Common questions
How many essentials were called?
463 genes (~22%).
What growth condition?
In vitro survival/growth on blood agar.
What method?
Mariner Tn-seq with quantitative sequencing.
Are all essentials universal?
No—about 21% lack DEG homologues and may be niche-specific.
More on Host–pathogen