Bacteria and Archaea

A set of flashcards covering essential concepts and vocabulary related to Bacteria and Archaea.

Why do biologists study Bacteria and Archaea?

To understand diseases, bioremediation, extremophiles, and global change.

Pathogens

A small percentage of bacteria that cause disease.

Extremophiles

Bacteria and archaea that live in extreme environments, utilizing special enzymes.

Global changes caused by bacteria

Include the oxygen revolution, nitrogen cycle, and eutrophication.

Bioremediation

The use of bacteria and archaea to degrade toxic pollutants.

Biostimulation

Fertilizing a contaminated site to promote growth of existing bacteria.

Seeding

Adding specific species of bacteria to contaminated sites for remediation.

Restriction Enzymes

Enzymes used in gene editing, which recognize and cut specific DNA sequences.

CRISPR Cas Enzymes

A gene editing system and bacterial defense against DNA viruses and plasmids.

Taq polymerase

An enzyme used in PCR, isolated from bacteria in hot springs of Yellowstone.

Oxygen revolution

Event where cyanobacteria produced enough oxygen for aerobic respiration.

Nitrogen Cycling

Involves fixing nitrogen and performing denitrification under anaerobic conditions.

Microbiome

The collection of microbes inhabiting a specific region, such as the gut microbiome.

Characteristics of bacteria and archaea

Prokaryotic and unicellular with lack of a nuclear envelope and organelles.

Gram positive bacteria

Stain purple, have extensive exposed peptidoglycan, and respond to penicillin-like drugs.

Gram negative bacteria

Stain pink, have less peptidoglycan, shielded by an outer membrane.

Enrichment culture

Method to culture specific bacteria by replicating growing conditions.

Direct sequencing

Method to study bacteria by extracting and sequencing DNA from environmental samples.

Robert Koch

Founder of modern bacteriology, linked specific bacteria to specific diseases.

Germ theory of disease

Theory that infectious diseases are caused by bacteria and viruses.

Lateral gene transfer

Transfer of genes between species, enhancing metabolic diversity in bacteria.

Transformation

Process of bacteria taking up DNA from the environment or host and integrating it.

Conjugation

Transfer of genetic information between bacteria through direct cell-to-cell contact.

Transduction

Transfer of genetic material through viruses.

Phototrophs

Bacteria that produce ATP using light energy.

Chemiosmosis

Process where potential energy across a membrane is converted into ATP.

Fermentation

Making ATP without an electron transport chain, less efficient than respiration.

Autotrophs

Organisms that manufacture their own carbon.

Heterotrophs

Organisms that obtain carbon by consuming other organisms.

Major lineages of bacteria

Include actinobacteria, chlamydiae, cyanobacteria, firmicutes, proteobacteria, spirochaetes.

Actinobacteria

Gram positive bacteria with high GC content, varied shapes.

Chlamydiae

Small, spherical, gram negative bacteria that live as parasites.

Cyanobacteria

Gram negative, photoautotrophic bacteria that produce oxygen and nitrogen.

Firmicutes

Gram positive bacteria, including species capable of forming spores.

Proteobacteria

Diverse group of gram negative bacteria with a variety of metabolic types.

Spirochaetes

Corkscrew-shaped, gram negative bacteria known for their distinctive morphology.

Crenarchaeota

Archaea found in hot springs, capable of diverse metabolism.

Euryarchaeota

Archaea with broad diversity in morphology and metabolic pathways.

Thaumarchaeota

Recently discovered rod-shaped archaea that are chemolithoautotrophic.