Ch 11: Prokaryotes: Domains, Bacteria, and Archaea Flashcards
What phylum contains mostly chemoheterotrophic bacteria and is the largest taxonomic group of bacteria? Gram-positive or Gram-negative?
- Proteobacteria
- Gram-negative
What are the subclasses of proteobacteria?
- Alpha-
- Beta-
- Gamma-
- Delta-
- Epsilon-
Identify the genus:
- Phylum: Alphaproteobacteria
- One of the most abundant microbes on Earth (accounts for 25% of ocean bacteria)
- Only one species (ubique) of this genus
- 0.3 μm diameter
- Simplest autonomously replicating cells (1,354 genes)
Pelagibacter (pel-aj’ē-bak-ter)
True or false. Pelagibacter contains no duplicate gene copies, viral genes, introns, or junk DNA.
True
How does Pelagibacter get its energy?
- Respiring organic carbon
- Using a light-driven proton pump (not photosynthesis)
Identify the genus
- Phylum: Alphaproteobacteria
- Found in low-nutrient aquatic environments (i.e. lakes)
- Produce prominent prostheca and has a dimorphic cycle
- Replicate by budding at hyphal tips
Hyphomicrobium
Identify the genus
- Phylum: Alphaproteobacteria
- Found in low-nutrient aquatic environments (i.e. lakes)
- Produce prominent prostheca and has a dimorphic cycle
- Produce stalks for anchoring to surfaces and increasing SA/Vol ratios
- Replicate by binary fission
Caulobacter
Identify the genus:
- Phylum: Alphaproteobacteria
- Nitrogen-fixing
- Enter the roots of leguminous plants and form nodules
- Endosymbiotic and cannot fix nitrogen independently from host plant
Rhizobium
Identify the genus:
- Phylum: Alphaproteobacteria
- Nitrogen-fixing
- Free-living on plant root surfaces commonly found on tropical grasses and sugarcane
- Uses nutrients excreted by plants and fixes nitrogen in return
Azospirillum
Identify the genus
- Phylum: Alphaproteobacteria
- Plant pathogen; invade plant cells but do not induce nodules or fix nitrogen
- Species tumefaciens induces crown gall disease in plants
Agrobacterium
Identify the genus:
- Phylum: Betaproteobacteria
- Nitrogen-fixing: NH4+ → NO2-
- Chemoautotroph (oxidize nitrogen for energy and fix CO2)
Nitrosomonas
Identify the genus
- Phylum: Alphaproteobacteria
- Part of the nitrogen cycle: NO2- → NO3-
- Chemoautogrph (oxidize nitrogen for energy and fix CO2)
Nitrobacter
What is a facultative intracellular parasite?
Microbe that can reproduce outside or inside of the cells
Identify the species
- Phylum: Alphaproteobacteria
- Facultative intracellular parasite
- 40% of cats carry it in their mouths or under their claws; acquired from infected fleas
- Bacillus inhabits cat’s RBCs
- Primary mode of transmission to humans is infected flea feces
- “Cat-scratch fever”
Bartonella henselae
Identify the genus:
- Phylum: Alphaproteobacteria
- Facultative intracellular parasite
- Different species infect cattle, swine, goats, sheep, dogs, and humans
- Spreads to humans by contact with animals or ingestion of undercooked meat or unpasteurized dairy products
- Can survive in phagosomes of macrophages by blocking lysosomal fusion
- Causes Brucellosis
Brucella
What is an obligate intracellular parasite?
Microbe that requires a host to reproduce
Identify the genus
- Phylum: alphaproteobacteria
- Obligate intracellular parasite
- Pleomorphic (rods or coccobacilli)
- Transmitted to humans by insect or tick bites
- Prefers to infect endothelial cells lining blood vessels
- Cause several diseases known as the spotted fever group
Rickettsia
What species of Rickettsia causes epidemic typhus? How is it transmitted?
- R. prowazekii
- Transmitted through lice
What species of Rickettsia causes endemic murine typhus? How is it transmitted?
- R. typhi
- Transmitted through rat fleas
What species of Rickettsia causes rocky mountain spotted fever? How is it transmitted?
- R. rickettsii
- Transmitted through ticks
Identify the genus:
- Phylum: Alphaproteobacteria
- Obligate intracellular parasites
- Rickettsia-like bacteria
- Transmitted by ticks to humans and cause ehrlichiosis
- Survive phagosomes after phagocytosis in macrophages
Ehrlichia
Identify the genus:
- Phylum: Alphaproteobacteria
- Endosymbiont; lives in cells of insects and other invertebrates
- Not a human pathogen, but the most common infectious bacterial genus on Earth (infects over 1 million species)
- 20-75% of all insects are infected
- Complex interactions with hose; interfere with reproduction and egg development
Wolbachia
True or false. All betaproteobacteria are anaerobic
False. They are all aerobic
Identify the genus
- Phylum: Betaproteobacteria
- Relatively large cell bodies that twist like a spiral
- Habitat: freshwater (with one species exception)
- Motile due to bipolar tufts of flagella
Spirillum
____ is the largest species of Spirillum at 60 microns in length
Spirillum volutans
Identify the genus:
- Phylum: Betaproteobacteria
- Acidi-, Halo-, and Thermi- subtypes
- Oxidize reduced sulfur for energy and fix CO2 (participate in sulfur cycle)
Thiobacillus
Identify the genus:
- Phylum: Betaproteobacteria
- Rod-shaped with single polar flagella or tuft of flagella
- Found in soil
Burholderia
Identify the organism:
- Phylum: Betaproteobacteria
- First discovered as the cause of onion skin rot and then as a human pathogen
- Opportunistic pathogen that metabolizes respiratory secretions in cystic fibrosis patients
- Can grow in disinfectant
Burkholderia cepacia
Identify the organism:
- Phylum: Betaproteobacteria
- Cause of melioidosis, which is endemic in Southeast Asia and Northern Australia
Burkholderia pseudomallei
Identify the organism:
- Phylum: Betproteobacteria
- Pathogenic
- Nonmotile rods/coccobacilli
- Adhere to cilia of bronchial epithelium
- Causative agent of pertussis (whooping cough)
Bordetella pertussis
Identify the genus:
- Phylum: Betaproteobacteria
- Diplococci
- Use fimbriae to attach to mucous membranes in mammals
- Species meningitidis causes meningococcal meningitis
- Species gonorrhoeae causes gonorrhea
Neisseria
What is the largest subphylum of Proteobacteria?
Gammaproteobacteria
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Thiotrichales
- Oxidizes H2S and causes elemental sulfur to accumulate
- Largest known bacterium (100 - 300 micron diameter)
- Found in seafloor sediments of coastal waters off Namibia
Thiomargarita namibiensis
Identify the genus
- Phylum: Gammaproteobacteria
- Order: Pseudomonadales
- Aerobic rods with polar flagella (single or tufts); common in soil
- Opportunistic pathogen of urinary tract, burns, and wounds
- Responsible for food spoilage (grow at refrigeration temps)
Pseudomonas
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Pseduomondales
- Aerobic nonmotile rods found in soil and water
- Opportunistic pathogen found in hospital settings; primary respiratory but can infect skin, etc.
- Rapidly becomes resistant to antibiotics and disinfectants
- Survive on surfaces for weeks
Acinetobacter baumanii
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Pseduomondales
- Aerobic coccobacilli
- One of several organisms that can cause conjunctivitis
Moraxella lacunate
Identify the organism (2)
- Phylum: Gammaproteobacteria
- Order: Psudomondales
- Large ovoid heavily capsulated bacteria
- Free living in soil that fix nitrogen
Azotobacter and Azomonas
Identify the genus:
- Phylum: Gammaproteobacteria
- Order: Legionellales
- Found in streams , warm-water pipes, HVAC cooling towers
- Facultative intracellular parasites
- Humans are accidental hosts by inhalation of contaminated water droplets
Legionella
What organism is responsible for Legionnaires disease (pneumonia)?
Legionella pneumophilia
Identify the organism
- Phylum: Gammaproteobacteria
- Order: Legionellales
- Highly infectious; transmitted to humans via inhalation of animal derived dusts, aerosols, or contaminated milk
- Potential bioweapon
- Causes flu-like pneumonia called Q fever
- Highly resistant to environmental stresses
Coxiella burnetti
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Vibrionales
- Facultative anaerobic curved rods
- Mostly found in aquatic environments
- Responsible for causing cholera through infected water
Vibrio cholerae
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Vibrionales
- Facultative anaerobic curved rods
- Mostly found in aquatic environments
- Responsible for causing gastroenteritis from eating raw or uncooked shellfish
Vibrio parahaemolyticus
What is the only Family under the Order of Enterobacteriales?
Enterobacteriaceae
Identify the order:
- Facultative anaerobic rods
- Also called “enterics”
- Ferment glucose and other sugars
- Have peritrichous flagella (if motile)
- Fimbriae to aid with adhesion
- Sex pili for exchange of genetic material (especially antibiotic resistance)
Enterobacteriales
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- Common inhabitant of human intestinal tract, but not most abundant (0.1% of gut flora)
- A great deal is known about its biochemistry and genetics
- Some strains produce Shiga toxin or enterotoxins that act on intestinal wall
- Presence in food indicates fecal contamination
Escherichia coli
Identify the genus:
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- 2 species identified: enterica and bongori
- Can contaminate food under unsanitary conditions
Salmonella
Identify the genus
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- 4 known species; all responsible for shigellosis/bacillary dysentery (species dysenterie most extreme)
- Only found in humans; no other natural reservoirs have been proven
Shigella
Identify the genus:
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- Common in soil and water
- Many can siolate and fix nitrogen
- pneumoniae species can cause pneumonia
Klebsiella
Identify the organism:
- Phylum: gammaproteobacteria
- Order: Enterobacteriales
- Destinguished by production of red pigment
- Opportunistic pathogen; cause many hospital acquired urinary, respiratory, and wound infections
Serratia marcescens
Identify the genus
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- Opportunistic pathogen if they enter the urinary tract or wound
- Multicellular behavior on agar (form concentric rings)
- Motile on solid surfaces
Proteus
Identify the organism:
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- Causes plague (black death of medieval Europe)
- Flea bits generally transmit bacteria from animals to humans as well as inhalation of respiratory droplets
Yersinia pestis
Identify the genus
- Phylum: Gammaproteobacteria
- Order: Enterobacteriales
- Their presence in the intestinal tracts of animals results in their wide distribution in soil, water, and sewage
- Pathogenic species can both cause urinary and hospital acquired infections
Enterobacter
What two species of Enterobacter are known to cause disease?
- E. cloacae
- E. aerogenes
Identify the genus
- Phylum: Gammaproteobacteria
- Order: Pasteurellales
- Primarily pathogens of domestic animals
- multocida species can be transmitted to humans via dog and cat bites
- Especially virulent present in Komodo dragon saliva
Pasteurella
Identify the genus:
- Phylum: Gammaproteobacteria
- Order: Pasteurellales
- Pathogens that inhabit mucus membranes of the upper respiratory tract, mouth, vagina, and intestinal wall
- named for its blood requirement in culture media
Haemophilus
Identify the species:
- Phylum: Gammaproteobacteria
- Order: Pasteurellales
- Genus: Haemophilus
- Mistakenly considered to be the cause of influenza
- Actually causes: meningitis, earaches, bronchitis, pneumonia, or septic arthritis
H. influenzae
Identify the species:
- Phylum: Gammaproteobacteria
- Order: Pasteurellales
- Genus: Haemophilus
- Causes the STD chancroid
H. ducreyi
Identify the species:
- Phylum: Gammaproteobacteria
- Order: Pasteurellales
- Genus: Haemophilus
- Causes the STD chancroid
H. ducreyi
Identify the genus
- Phylum: Deltaproteobacteria
- Attach tightly to other gram-negative bacteria, penetrates the outer layer, and enters the periplasm
- Breaks down host cell molecules to use elongate and form filaments
Bdellovibrio
Members of the order _______ are sulfur reducing bacteria that play a key role in the sulfur cycle.
Desulfovibrionales
Identify the genus:
- Phylum: Deltaproteobacteria
- Order: Desulfovibrionales
- Obligate anaerobes found in sediments and intestinal tracts of humans and animals
- Black color of sediments is due to H2S reacting with iron to form insoluble FeS
Desulfovibrio
Species of the order _____ are predatory upon other bacteria.
Myxococcales
Species of the order _____ are predatory upon other bacteria.
Identify the genus:
- Phylum: Deltaproteobacteria
- Order: Myxococcales
- Vegetative cells move by gliding motility and leave slime trail obtaining nutrition from bacteria they encounter
- Cooperative predation accomplished by secretion of antibiotics and lytic compounds to immobilize and degrade prey organism
Myxococcus
Members of the phylum _____ are slender rods that are helical or curved.
Epsilonproteobacteria
Identify the organism
- Phylum: Epsilonproteobacteria
- Microaerophilic
- Moltile by single polar flagella
- causes foodborne gastroenteritis
Campylobacter jejuni
Identify the organism
- Phylum: Epsilonproteobacteria
- Microaerophilic
- Moltile by single polar flagella
- Causes spontaneous abortion in domestic animals
Campylobacter fetus
Identify the organism:
- Phylum: Epsilonproteobacteria
- Multiple flagella
- Infect the lining of the stomach; most common cause of peptic ulcurs
- Associated with the development of stomach cancers
Helicobacter pylori
Identify the phylum:
- Gram-negative
- Oxygenic photosynthetic bacteria; use chlorophyll
- NOT eukaryotic algae
- Believed to have generated most of Earth’s atmospheric O2 millions of years ago
- Unicellular divide by binary fission
- Colonial have multiple visions
- Filamentous divide by fragmentation
Cyanobacteria
Is the phylum “Plantomycetes” Gram-Positive or Gram-Negative?
Gram- Negative
Identify the genus:
- Phylum: Planctomycetes
- Acquadic budding bacteria
- Produce stalks like Caulobacter
Planctomyces
Identify the organism:
- Phylum: Planctomycetes
- Model organism for the origin of the eukaryotic nucleus
- Double internal membrane around DNA like a nuclear membrane (nucleoid)
Gemmata obscuriglobus
Identify the phylum:
- Gram-negative
- Remarkably diverse
- Obligate intracellular parasites
- Direct transmission: interpersonal contact or aerosols
- Lab cultivation is difficult; requires lab animals, cell culture, or yolk of embryonated chicken eggs
Chlamydiae
Identify the organism:
- Phylum: Chlamydiae
- Different serovars are responsible for different diseases such as:
- Trachoma (leading cause of blindness in developing countries)
- Nongonococcal urethritis
- Lymphogranuloma venerum
Chlamydia trachomatis
Identify the organism:
- Phylum: Chlamydiae
- Causes mild form of pneumonia
Chlamydophila pneumoniae
Identify the organism:
- Phylum: Chlamydiae
- Causes respiratory disease Psittacosis
Chlamydophila psittaci
Identify the phylum:
- Name is derived from their coiled morphology
- Motile by rotating axial filaments
- May inhabit the muna oral and vaginal cavities
Spirochaetes
Identify the organism:
- Phylum: Spirochaetes
- Causative agent of Lyme disease
- Transmitted from ticks or lice to humans
Borrelia burgdorferi
Identify the genus:
- Phylum: Spirochaetes
- Causes Leptospirosis
- Transmitted from animals to humans through contaminated water
Leptospira
Identify the organism:
- Phylum: Spirochaetes
- Causative agent of Syphillis
Treponema pallidum
Is the phylum “Bacteroides” aerobic or anaerobic? Gram-Negative or Gram-Positive?
- Anaerobic
- Gram-Negative
Identify the genus:
- Phylum: Bacteroides
- Rod-shaped, non-motile, non-endospore forming
- Common inhabitant of GI tract
- Some species found in gingival crevices
- Cause infection at surgical sites, puncture wounds, and perforated bowels
Bacteroides
Identify the phylum:
- Anaerobic
- Gram-Negative
- Often pleiomorphic, but may be spindle-shaped
Fusobacteria
Identify the genus:
- Phylum: Fusobacteria
- Primarily found in mouth and associated with dental diseases
- Can be pathogenic to other parts of the body
Fusobacterium
Members of the phylum _______ appear to stain Gram-positive due to a thick cell wall, however they have an outer membrane so they are closer in structure to Gram-negative
Deinococcus-Thermus
Identify the organism
- Phylum: Deinococcus-Thermus
- More resistant to radiation than endospores (survive 1500x the lethal human dose)
- Reistance is due to rapid repair of radiation damage, which also extends to chemical mutagens
Deinococcus radiodurans
Identify the organism:
- Phylum: Deinococcus-Thermus
- Was isolated from a hot spring in Yellowstone National Park
- Source of Taq polymerase
Thermus aquaticus
Gram positive bacteria can be divided based on:
G/C content of their genetic material
- Phylum Firmicutes: Low G/C
- Phylum Tenericutes: Low G/C
- Phylum Actinobacteria: High G/C
Identify the genus:
- Phylum: Firmicutes
- Order: Clostridium
- common in soil
- Form endospores
- Obligate anaerobes
- Rod-shaped
Clostridium
Identify the species:
- Phylum: Firmicutes
- Order: Clostridiales
- Genus: Clostridium
- Responsible for some GI tract infections
C. difficile
Identify the species:
- Phylum: Firmicutes
- Order: Clostridiales
- Genus: Clostridium
- Cause tetanus
C. tetani
Identify the species:
- Phylum: Firmicutes
- Order: Clostridiales
- Genus: Clostridium
- Cause food poisoning
C. botulinum
Identify the species:
- Phylum: Firmicutes
- Order: Clostridiales
- Genus: Clostridium
- Cause foodborne diarrhea
C. perfringens
Identify the genus:
- Phylum: Firmicutes
- Order: Clostridiales
- Nutrionally symbiotic with gut of Red Sea sturgeon fish (Dory)
- Can be seen with naked eye
- Breaks the known rules of dize/diffusion limitations
- Has tens of thousands of copies of its genome
- Daughter cells burst cell wall of mother cell
Epulopiscium
Identify the genus:
- Phylum: Firmicutes
- Order: Bacillales
- Endospore-forming rods
- Obligate aerobes or facultative anaerobes
- Common in soil and form in chains in culture
- Produce antibiotics
- Only species are pathogenic to humans
Bacillus
Identify the species:
- Phylum: Firmicutes
- Order: Bacillales
- Genus: Bacillus
- Disease of cattle, sheep, and horses that can be transmitted to humans (linked with bioterrorism)
B. anthracis
Identify the species:
- Phylum: Firmicutes
- Order: Bacillales
- Genus: Bacillus
- Agriculturally important insect pathogen used as a pssticide
B. thuringiensis
Identify the species:
- Phylum: Firmicutes
- Order: Bacillales
- Genus: Bacillus
- Associated with food poisoning, typically through infection of starchy foods
B. cereus
Identify the genus:
- Phylum: Firmicutes
- Order: Bacillales
- Cocci bacteria that arrange themselves in grape-like clusters
- Considered part of our normal flora
- Grow well in high osmotic pressure, low moisture conditions (nasal passages and skin)
Staphylococcus
Identify the species:
- Phylum: Firmicutes
- Order: Bacillales
- Genus: Staphylococcus
- Golden in color (may protect from antimicrobial effects of sunlight)
- Produce many exotixins
- Commonly infect surgical wounds
- Quickly develop antibiotic resistance
S. aureus
S. aureus infections differ by anatomical region
- Vaginal tract = ?
- GI tract = ?
- Respiratory tract = ?
- Toxic shock syndrome
- Food poisoning
- Sinus infections
Identify the genus:
- Phylum: Firmicutes
- Order: Lactobacillales
- Produce lactic acid
- Commercially important in pickle, yogurt, sauerkraut, and buttermilk production
- Aerotolerant anaerobes
- In humans it can be found in the oral cavity, vaginal, and GI tracts
Lactobacillus
Identify the genus
- Phylum: Firmicutes
- Order: Lactobacillales
- Cocci bacteria that typically grow in chains
- Responsible for more illnesses and greater variety of diseases than any other genus
- Express and secrete substances that aid in its pathogenicity
Streptococcus
What type of Streptococci is the most virulent? Alpha, Beta, or Gamma? Why?
- Beta
- Express hemolysin that lyses RBCs
What is the causative agent of Scarlet and Rheumatic Fever?
Streptococcus pyogenes
Identify the genus:
- Phylum: Firmicutes
- Order: Lactobacillales
- Part of our normal intestinal flora
- Occasionally cause UTIs and sepsis
- Adapted to nutrient rich, low oxygen body regions (GI, oral cavity, vagina)
- Major cause of hospital-acquired infections
- Persist on inanimate objects for long periods
- High antibiotic resistance
Enterococcus
Identify the organism:
- Phylum: Firmicutes
- Order: Lactobacillales
- Usual causative agent of food listerosis and spoilage
- Most virulent foodborne pathogen (20-30% of clinical infections result in death)
- Can survive phaocytosis
- Pose risk for a developing fetus
Listeria monocytogenes
Identify the genus:
- Phylum: Tenericutes
- Order: Mycoplasmatales
- Lack cell wall; pleomorphic
- Produce filaments resembling those of fungi
- Believed to be the smallest, self-replicating, free-living life forms (0.1 - 0.24 microns)
Mycoplasmas
Identify the genus
- Phylum: Actinobacteria
- Common soil isolate
- Reproduce via asecual spores (conidiospores)
- Strick aerobes
- Produce gaseous compound geosmin that gives soil its musty odor
- Produce most of our commercial antibiotics
Streptomyces
Identify the organism:
- Phylum: Actinobacteria
- Exhibit filamentous growth
- Acid-fast staining; not Gram-positive
- Resistant to environmental stressors like drying
- Causative agent for tuberculosis
Mycobacterium tuberculosis
Identify the organism:
- Phylum: Actinobacteria
- Gram-negative
- Exhibit filamentous growth
- Acid-fast staining
- Resistant to environmental stressors like drying
- Causative agent for leprosy
Mycobacterium leprae
Identify the genus
- Phylum: Actinobacteria
- Facultative anaerobes
- Branched filaments that replicate by fragmentation
- Common in soil and animal microbiota (mouth and throat of humans)
Actinomyces
What organism is the causative agent of actinomycosis? Symptoms?
- Actinomyces israelii
- Destroys tissue of the head, neck, and lungs
Identify the genus:
- Phylum: Actinobacteria
- Morphogically similar to Actinomyces
- Aerobic
- Acid-fast
Nocardia
Identify the organism:
- Phylum: Actinobacteria
- Pleomorphic; morphology changes with age
- Causative agent of diphteria
Corynebacterium diphtheriae
Identify the organism:
- Phylum: Actinobacteria
- Named for its ability to form propionic acid
- Commonly found on human skin and are the primary cause of acne
Propionibacterium acnes