Firmicutes

Definition

Firmicutes are a phylum of predominantly Gram-positive bacteria with thick cell walls. They play a significant role in the human microbiota, particularly in the respiratory and digestive systems.

5 Must Know Facts For Your Next Test

1. Firmicutes include important genera such as Lactobacillus, Clostridium, and Streptococcus.
2. These bacteria are involved in metabolic processes like fermentation within the gut.
3. An imbalance of Firmicutes in the gut has been linked to conditions such as obesity and irritable bowel syndrome (IBS).
4. In the respiratory tract, certain Firmicutes can be pathogenic, contributing to infections like pneumonia.
5. Firmicutes produce endospores, which allow them to survive harsh conditions and contribute to their resilience.

Review Questions

• What are some key genera within the Firmicutes phylum?
• How do Firmicutes contribute to metabolic processes in the digestive system?
• What role do Firmicutes play in respiratory infections?

Related terms

Bacteroidetes: A phylum of Gram-negative bacteria that also form part of the gut microbiota.

Lactobacillus: A genus within Firmicutes known for its role in fermenting lactose into lactic acid.

Clostridium: A genus of Firmicutes that includes species responsible for diseases like tetanus and botulism.