Bacterial Diversity: Cyanobacteria and Gram-Positive

These flashcards cover the key concepts of bacterial diversity, including classifications, metabolic types, structural features, major phyla, and specific genera related to Cyanobacteria and Gram-positive bacteria.

What are the three major groups of Gram-positive bacteria?

Firmicutes, Tenericutes, and Actinobacteria.

Which phylum is known as oxygenic phototrophs?

Cyanobacteria.

What characteristic do most bacterial cells possess that is a target for antibiotics?

Cell walls made of peptidoglycan.

What is a 'phylum' in the context of bacterial classification?

A group of bacteria sharing a common ancestor based on small-subunit rRNA sequences.

Name two types of metabolism found in bacteria.

Heterotrophy and phototrophy.

What is unique about the cell structure of Cyanobacteria?

They are the only oxygenic phototrophic prokaryotes and contain chlorophyll.

What is the role of heterocysts in filamentous Cyanobacteria?

They are specialized cells for nitrogen fixation.

Describe the metabolism of Bacteroidetes bacteria.

Obligate anaerobic fermenters that produce acetate and succinate.

What are deep-branching Gram-negative microbes known for?

Diverse metabolism and morphology, having diverged distantly from Proteobacteria.

How do extreme thermophiles like Aquificae and Thermotogae adapt?

They can thrive at temperatures above 80°C and have unique DNA repair mechanisms.

What are some characteristics of the phylum Firmicutes?

Includes spore-forming bacteria, such as the genera Bacillus and Clostridium.

What is an important feature of Streptomyces bacteria?

They are major antibiotic producers and form filamentous mycelia.

Why are genera like Mycoplasma significant in the context of Tenericutes?

They have completely lost their cell wall and are pleomorphic.

How do actinomycetes associate with other organisms in their environments?

They often form mutualistic relationships, such as with sponges and leaf-cutter ants.

What are Rickettsia classified as?

Obligate intracellular pathogens.

What distinguishes the phylum Chlorobi?

They are green sulfur bacteria that use photosynthesis with H2S as an electron donor.