Fig 1.
Growth stimulation of ‘difficult-to-culture’ oral bacterial strains by siderophores.
(a-f) Growth of Prevotella sp. HOT-376: (a) Fusobacterium nucleatum cross-streak, (b-f) 4- & 8-d plates with pyoverdines-Fe, F. nucleatum culture supernatant (positive control) or water (negative control); (g-i) Fretibacterium fastidiosum: 28-day spread plates supplemented with desferricoprogen, positive or negative control solutions (as described above).
Table 1.
Growth stimulation of Prevotella sp. HOT-376 and Fretibacterium fastidiosum by test agents relative to positive (++++) and negative (-) controls.
Fig 2.
Secondary cultures of colonies of interest.
(a) Growth of an unknown strain limited to the surface of a Propionibacterium acnes cross-streak (on left); (b) Secondary culture of Bacteroidaceae bacterium HOT-272 showing satellitism beside the P. acnes cross-streak (on left) and around red colonies of Actinomyces odontolyticus (indicated with arrows).
Fig 3.
Phylum Chloroflexi isolate Anaerolineae bacterium HOT-439 is dependent on a helper strain for growth.
12-d growth: (a) with and (b) without F. nucleatum cross-streaks
Fig 4.
Differential growth-stimulation of Bacteroidetes bacterium HOT-365 in accordance with the ‘helper’ used at initial passage.
Eight-day cultures with cross-streaks of P. acnes (on left) and F. nucleatum (on right). (a, c) Forth and (b, d) sixth passages after initial sub-culture on membranes over P. acnes (a-b) or F. nucleatum (c-d) lawns.
Fig 5.
Plate cultures showing unusual helper- / dependent-strain relationships.
(a) 14d-culture of Fretibacterium fastidiosum with bilateral cross-streaks of F. nucleatum–small circular zone of inhibition (top left) localised to an area beside the ‘helper’; (b) Five-day culture of Prevotella sp. HOT-376 showing self-satellitism–growth restricted to the site of, and immediately beside two vertical cross-streaks of self.
Table 2.
Previously-uncultivated phylotypes detected in subgingival plaque samples and cultures derived from those samples.
Table 3.
Previously-cultivated but uncharacterised / unnamed taxa detected in subgingival plaque samples and cultures derived from those samples.
Table 4.
‘Unclassified’ sequences representing previously-uncultivated phylotypes detected in subgingival plaque samples and cultures derived from those samples.