The bacterium Porphyromonas gingivalis is a common component…

The bacterium Porphyromonas gingivalis is a common component of dental plaque and can contribute to gum disease. When colonizing a new tooth, P. gingivalis does not start producing proteins needed to make a sticky biofilm until there are a relatively large number of the bacteria gathered. This is likely an example of…

In anaerobic conditions like deep ocean sediment, the bacter…

In anaerobic conditions like deep ocean sediment, the bacterium Desulfovibrio vulgaris is often found living together with archaea from the genus Methanospirillum. D. vulgaris can break down the carbon source formate for energy, but this produces H2, which inhibits growth of D. vulgaris. Methanospirillum archaea consume H2 in their main energy-producing metabolic pathway. Which of the following best describes this situation? Which of the following best describes this situation?