Prokaryotes and Bacteria

Flashcards covering prokaryotes, bacteria, and archaea, including their characteristics, classifications, and pathogens.

What are the two domains into which prokaryotes are grouped according to Bergey's Manual of Systematic Bacteriology?

Bacteria and Archaea

In prokaryotes, where is the DNA located since they have no true nucleus?

A place called the nucleoid

Which scientist first defined cells having no nucleus?

Edward Chatton (1937)

According to Roger Stanier (1961), what defines prokaryotic cells?

Cells in which the nuclear material is not surrounded by a nuclear membrane

What kingdom did Robert Murray (1968) propose for prokaryotes?

Kingdom Prokaryotae

In Robert Whittaker's five-kingdom system (1969), which kingdom were prokaryotes placed in?

Monera

According to Carl Woese (1978), what domain includes animals, plants, fungi, and protists?

Domain Eukarya

The discovery of three cell types by Carl Woese was based on what observation?

Sequencing of 16S ribosomal RNA

What is a key characteristic of Domain Archaea that distinguishes them from bacteria?

Lack peptidoglycan in their cell walls

Where do archaea typically thrive due to their unique adaptations?

Extremely harsh environments of heat, cold, acidity, and pressure

What is the physiological diversity of organisms in the Domain Archaea?

Aerobic, facultative anaerobic, and strictly anaerobic

What are two key distinguishing features found in the cells of Domain Archaea?

Unusual lipids in their cell membranes and distinctive RNA molecules in their cytoplasm

What are some basic archaeal shapes?

Coccus, lobed coccus, short bacillus, and elongate bacillus.

What are the three major groups into which archaea are classified?

Methanogens, Halophiles, and Hyperthermophiles

What metabolic process defines methanogens, and what is the product?

Strict anaerobes that produce methane (CH4) from carbon dioxide and hydrogen

Where are Methanococcus and Methanobacterium commonly found?

Swamps, sewage, and other areas of decomposing matter

What environmental condition is essential for halophiles to thrive?

Require high concentrations of salt for survival

Where are Halobacterium halobium and Halococcus typically found?

Great Salt Lake

What type of environment do hyperthermophiles typically grow in?

Hot, acidic environments

Which archaea survive in acidic, sulfur-rich hot springs?

Sulfolobus archaea

Where do Pyrococcus furiosus survive in extraordinarily high temperatures?

Sea vents

Which group of archaea contains most thermophilic archaea?

Crenarchaeota

What compounds do Crenarchaeota use as electron donors or acceptors?

Sulfur compounds

Which types of archaea are included in the Euryarcheota group?

Methanogens, halophiles, and thermophiles

Where is Korarchaeota typically found?

Hot springs

Name some members of Euryarchaeota

Halobacteriales, Methanopyrales, Archeoglobales, Methanomicrobiales, Methanococcales, Methanobacteriales, Thermococcales, Thermoplasmales

What role do some prokaryotes in the Domain Bacteria play in terms of disease?

Pathogenic prokaryotes (infectious diseases)

What theory explains the origin of eukaryotes from ancient bacteria?

Endosymbiotic theory

According to endosymbiotic theory, what organelles originated from ancient bacteria?

Mitochondria and chloroplasts

Describe the basic structure of bacteria.

Simple, single-celled organisms

What unique compound is found in the cell walls of bacteria?

Peptidoglycan layer

Name two of the largest bacteria that are visible to the unaided eye.

Thiomargarita namibiensis and Epulopiscium fishelsoni

Which genus contains the smallest bacteria, measuring only 0.3 micrometres?

Mycoplasma

What are bacteria called if they form a parasitic association with other organisms?

Pathogens

Name some of the diseases caused by pathogenic bacteria.

Cholera, syphilis, anthrax, leprosy, bubonic plague, respiratory infections, tetanus, typhoid fever, diphtheria, foodborne illness

Which bacteria can cause skin infections, pneumonia, meningitis, and even overwhelming sepsis?

Staphylococcus or Streptococcus

Name a type of bacteria that are obligate intracellular parasites and cause diseases like typhus and Rocky Mountain spotted fever.

Rickettsia

Approximately how many people are killed by tuberculosis alone each year?

2 million

Which phylum of obligate intracellular parasites can cause pneumonia, urinary tract infections, and may be involved in coronary heart disease?

Chlamydia

Give examples of opportunistic pathogens that cause disease mainly in people suffering from immunosuppression or cystic fibrosis.

Pseudomonas aeruginosa, Burkholderia cenocepacia, and Mycobacterium avium

Evidence in the fossil record indicates that prokaryotes are about how old?

2.5 billion years

Classically, how have bacteria been grouped rather than on their evolutionary relationships?

Structure, Physiology, Molecular Composition, and Reaction to specific types of stains (Gram Stain)

Where is the diversity of bacterial species determined by publication?

International Journal of Systematic Bacteriology and Bergey's Manual of Systematic Bacteriology

Which committee maintains international rules for naming bacteria?

The International Committee on Systematic Bacteriology (ICSB)

According to Bergey's Manual of Systematic Bacteriology, which domain is composed of 22 phylum?

Domain Bacteria

Which phylum is the largest taxonomic group of bacteria?

Phylum Proteobacteria

What types of bacteria are included in phylum Proteobacteria?

Gram negative, chemoheterotrophic bacteria

What basis are bacterial species named and grouped upon?

Cell structure, cellular metabolism or on differences in cell components

What is the phylogenetic relationship based upon in bacterial classification?

rRNA studies.

Under what nutrient conditions can alpha proteobacteria grow?

Low levels of nutrients

What types of bacteria are included in the alpha proteobacteria?

Agriculturally important bacteria capable of inducing nitrogen fixation in symbiosis with plants, and several plant and human pathogens

Describe Azospirillum

A soil bacterium that grows in close association with the roots of plants, fixes nitrogen from the atmosphere

What do Acetobacter and Gluconobacter convert?

Convert ethanol into acetic acid (vinegar)

What shape are Rickettsia bacteria?

Rod shape or cocobacilli

How are Rickettsia typically transmitted to humans?

Bites of insects and ticks

What group of diseases are Rickettsia known as?

Spotted fever group

How is Epidemic typhus (R.prowazekii) transmitted?

Lice

How is the Endemic murine typhus (R. typhi) transmitted?

Rat fleas

How is Rocky mountain spotted fever (R.rickettsii) transmitted?

Ticks

What do rickettsial infections do in humans?

Damage the permeability of blood capillaries

What are gram negative rickettsia like bacteria that lived obligately within white blood cell?

Ehrlichia

How is Ehrlichia transmitted?

Ticks to human

What do Rhizobium and Agrobacterium do?

Infect roots of leguminous plants and fix nitrogen from the atmosphere

What disease does the Agrobacterium tumefaciens cause?

Crown gall

What are all species of Brucella?

Obligate parasites of mammals

What type of organisms are Nitrobacter and Nitrosomonas?

Nitrifying bacteria

What do Beta Proteobacteria use?

Use nutrients substances that diffuse away from areas of anaerobic decomposition of organic matter

Name some of the molecules that diffuse away from areas of anaerobic decomposition of organic matter.

Hydrogen gas, ammonia, and methane

Thiobacillus species are important in what cycle?

sulfur cycle

Where are Spirilum mainly habitat?

Fresh water

How are Spirilum motile?

Polar flagella

Where are Sphaerotilus commonly found?

Freshwater and in sewage

How are Burkholderia motile?

Single or tuft polar flagella

What does Burkholderia cepacia most often cause in immunocompromised individuals?

Pneumonia

Describe the characteristics of Bordetella species.

Non motile, aerobic, gram negative rod

What disease does Bordetella pertussis cause?

Whooping cough

What are Neisseria?

Aerobic, gram negative cocci

What does Neisseria gonorrheae cause?

Gonorrhea

What does Neisseria meningitides cause?

Meningococcal meningitis

Where is Zoogloea used?

Aerobic sewage treatment processes

What is the size of gamma proteobacteria?

Largest subgroup of proteobacteria

What media do Francisella need to grow upon?

Complex media enriched with blood or tissue extracts

What disease does Francisella tularensis cause?

Tularemia

What are Pseudomonas classifed as?

Gram negative motile aerobic rods

What does Pseudomonas aeruginosa infect?

Urinary tract, burns, wounds and can cause septicemia, and meningitis

What is P. syringae?

Plant pathogen

What type of bacteria are Azotobacter and Azomonas?

Nitrogen fixing bacteria

Where do Azotobacter and Azomonas live?

Soil

What are Moraxella?

Aerobic gram negative coccobacilli

What is Moraxella lacunata implicated in?

Conjunctivitis

What does Legionella cause?

Pneumonia like disease called legionellosis

What do Coxiella burnetii require to reproduce?

Mammalian host cell

What are facultative anaerobic gram negative slightly curved rods?

Vibrionales

What does Vibrio cholerae cause?

Cholera

How is V.parahaemolyticus transmitted?

Raw or undercooked shellfish

What are facultative anaerobic gram negative rods that are motile?

Enterobacteriales

Where do Enterobacteriales inhabit?

Intestinal tract of humans and other animals

What are most enteric?

Fermenters of glucose and other carbohydrates

What is the most common inhabitants of human intestinal tract?

Escherichia coli

What is the presence of Escherichia coli in water and food an indication of?

An indication of fecal contamination