Prokaryotes: Vocabulary Flashcards

Vocabulary flashcards covering key terms from the lecture notes on characterization and classification of prokaryotes.

Prokaryotes

Most diverse group of cellular microbes; lack a membrane-bound nucleus; reproduce asexually.

Endospores

Defensive, dormant structures formed by some bacteria (e.g., Bacillus, Clostridium) to survive unfavorable conditions.

Archaea

Domain of prokaryotes with branched membrane lipids and no peptidoglycan in cell walls; inhabit extreme environments.

Branched hydrocarbon lipids

Distinctive membrane lipids in Archaea that contribute to stability in extreme conditions.

No peptidoglycan in archaeal cell walls

Archaea lack the peptidoglycan layer found in many bacterial cell walls.

Thermophiles

Archaea that require higher temperatures for growth; functional above ~45°C.

Hyperthermophiles

Thermophiles that require temperatures over 80°C.

Geogemma

Representative genus of hyperthermophilic archaea.

Pyrodictium

Representative genus of hyperthermophilic archaea.

Halophiles

Archaea that inhabit extremely saline environments and often have red/orange pigments.

Halobacterium salinarium

Halophilic archaeon commonly cited as a model halophile.

Methanogens

Archaea that produce methane by converting CO2 and H2; found in anaerobic environments.

Methanobacterium

Genus of methanogenic archaea.

Sulfolobus

Sulfolobus: a genus of thermoacidophilic archaea often found in hot, acidic environments.

Cyanobacteria

Oxygenic photosynthetic prokaryotes; some fix nitrogen with heterocysts; aquatic and gliding motility.

Heterocysts

Specialized nitrogen-fixing cells in certain cyanobacteria.

Mycoplasmas

Bacteria lacking a cell wall; pleomorphic; among the smallest free-living cells; often parasitic.

Staphylococcus aureus

Gram-positive cocci; facultative anaerobe; causes skin infections and toxin-related diseases.

Staphylococcus epidermidis

Gram-positive cocci; normal skin flora; opportunistic infections with implants.

Streptococcus pyogenes

Group A Streptococcus; produces extracellular toxins; can cause necrotizing fasciitis.

Streptococcus pneumoniae

Gram-positive diplococcus; causes pneumococcal pneumonia and meningitis.

Streptococcus mutans

Gram-positive cocci associated with dental caries.

Lactococcus lactis

Lactic acid bacterium used in dairy fermentation.

Enterococcus faecalis

Gram-positive cocci; part of normal gut flora; can cause nosocomial infections.

Clostridium

Gram-positive, endospore-forming rods; obligate anaerobes; includes several toxin producers.

Clostridium botulinum

Produces botulinum toxin; causes botulism.

Clostridium tetani

Produces tetanus toxin; causes tetanus.

Clostridium perfringens

Causes gas gangrene and food poisoning.

Clostridium difficile

Causes antibiotic-associated colitis and pseudomembranous colitis.

Bacillus

Gram-positive, regular rods; aerobes or facultative; includes several notable pathogens and biopesticides.

Bacillus anthracis

Causes anthrax.

Bacillus cereus

Causes food poisoning.

Bacillus thuringiensis

Biopesticide-producing Bacillus species.

Lactobacillus

Gram-positive rods; lactic acid bacteria; important in dairy fermentation and human microbiota.

Listeria monocytogenes

Gram-positive rod; facultative anaerobe; notable foodborne pathogen.

Epulopiscium fishelsoni

Extremely large bacterium; notable for unusual size.

Corynebacterium diphtheriae

Gram-positive rod; causes diphtheria.

Propionibacterium acnes

Gram-positive rod associated with acne.

Actinomyces israelii

Gram-positive branching filaments; causes actinomycosis.

Streptomyces griseus

Gram-positive, branching filament; producer of many antibiotics.

Nocardia asteroides

Gram-positive branching filaments; acid-fast; opportunistic infections.

Mycobacterium

Acid-fast, aerobic rods with mycolic acid; includes M. tuberculosis and M. leprae.

Bdellovibrio

Gram-negative predatory bacterium that invades other Gram-negative bacteria.

Spirillum

Gram-negative, helical/vibroid rod; motile.

Campylobacter jejuni

Gram-negative curved rod; a common cause of gastroenteritis.

Azospirillum

Gram-negative rod associated with plant roots; nitrogen fixer.

Rhizobium

Gram-negative rod; nitrogen fixer; forms nodules on legume roots.

Pseudomonas aeruginosa

Gram-negative rod; opportunistic pathogen; environmental versatility and biofilm formation.

Legionella pneumophila

Gram-negative rod; causes Legionnaires’ disease from water systems.

Francisella tularensis

Gram-negative coccobacillus; causes tularemia.

Burkholderia

Gram-negative rod; includes opportunistic pathogens (e.g., B. cepacia).

Bordetella pertussis

Gram-negative coccobacillus; causes whooping cough.

Brucella abortus

Gram-negative coccobacillus; causes brucellosis; zoonotic.

Agrobacterium

Gram-negative rod; plant pathogen; Ti plasmid used in crown gall.

Neisseria meningitidis

Gram-negative diplococcus; encapsulated; causes meningitis.

Neisseria gonorrhoeae

Gram-negative diplococcus; causes gonorrhea.

Escherichia coli

Gram-negative rod; lactose fermenter; normal gut flora; pathogenic strains include O157:H7.

Klebsiella pneumoniae

Gram-negative rod; lactose fermenter; nosocomial pneumonia and UTIs.

Salmonella typhi

Gram-negative rod; causes typhoid fever; human-restricted pathogen.

Salmonella enteritidis

Gram-negative rod; causes gastroenteritis from contaminated food.

Proteus vulgaris

Gram-negative rod; swarming motility; UTIs and wound infections.

Proteus mirabilis

Gram-negative rod; UTIs; urease production; can form stones.

Shigella flexneri

Gram-negative rod; causes shigellosis via fecal-oral spread.

Yersinia pestis

Gram-negative rod; causes bubonic plague; transmitted by fleas.

Serratia marcescens

Gram-negative rod; opportunistic pathogen; often red pigment production.

Pasteurella multocida

Gram-negative coccobacillus; animal bite infections.

Vibrio cholerae

Gram-negative curved rod; causes cholera with severe watery diarrhea.

Vibrio parahaemolyticus

Gram-negative curved rod; gastroenteritis from seafood.

Haemophilus influenzae

Gram-negative coccobacillus; requires X and V factors; causes meningitis and pneumonia.

Haemophilus ducreyi

Gram-negative coccobacillus; causes chancroid.

Enterobacter aerogenes

Gram-negative rod; nosocomial infections; UTIs and pneumonia.

Fusobacterium

Gram-negative anaerobe; associated with periodontal disease.

Bacteroides

Gram-negative obligate anaerobe; abundant in gut flora; opportunistic infections.

Rickettsia

Gram-negative intracellular parasites; transmitted by arthropods; causes typhus and RMSF.

Coxiella burnetii

Gram-negative intracellular bacterium; causes Q fever.

Ehrlichia

Gram-negative intracellular bacterium; causes ehrlichiosis.

Chlamydophila pneumoniae

Obligate intracellular; causes atypical pneumonia.

Chlamydophila psittaci

Causes psittacosis; pneumonia linked to birds.

Chlamydia trachomatis

Obligate intracellular; causes most common bacterial STI and conjunctivitis.

Leptospira

Spiral-shaped bacterium; causes leptospirosis; shed in urine.

Treponema pallidum

Spirochete; causative agent of syphilis.

Borrelia burgdorferi

Spirochete; causes Lyme disease; tick-borne.