Table 1. HMW DOM-enriched dilution to extinction cultivation experimental design and growth screen results. Forty-eight well plates were filled with TFF oligotrophic seawater amended with HMW DOM at 4x (280 μM) DOC, 10x (700 μM) DOC or non-amended and then inoculated with the diluted coastal bacterioplankton community.
| non-DOM | 4 × DOM | 10 × DOM | Total | |
|---|---|---|---|---|
| Wells | ||||
| Innoculated | 840 | 840 | 840 | 2520 |
| Controls | 54 | 54 | 54 | 162 |
| Cultures detected | ||||
| Innoculated | 1 | 40 | 52 | 93 |
| Controls | 0 | 0 | 0 | 0 |
Abbreviation: DOM, dissolved organic matter.
The 'controls' consisted of six wells on each treatment plate, as well as an entire microtiter plate, that contained the same media and DOM enrichment, but were not inoculated. Positive growth ('cultures detected') was defined as a well having a density of 105 or more cells per ml after 6–7 weeks of incubation and one round of redilution.