Lecture 15-16 Flashcards
What are Thylakoids?
Specialist systems in only Gram-negative phototrophs (ex. cyanobacteria) that maximize the photosynthetic capability of the cell
What are Carboxysomes?
Specialized protein microcompartments found in Gram-negative cells that fix CO2 using enzymes (ex. cyanobacteria)
What are Gas Vesicles?
Hollow proteins tubes that allow microbes to float by maintaining a set buoyancy (ex. Microcystis algal blooms)
What are the applications of cyanobacteria in real life?
1) The colour of flamingoes are from a cyanobacteria diet
2) Cyanobacteria produce highly potent toxins
3) Used as a dietary supplement and food source
4) Used in the production of eco-friendly renewable biodiesel/fuels
What are the classification parameters of microorganisms based on temperature?
1) Hyperthermophiles - Above 80°C
2) Thermophiles - Between 50-80°C
3) Mesophiles - Between 15-45°C
4) Psychrophiles - Below 15°C
What are the classification parameters of microorganisms based on pH?
1) Alkaliphiles - Above pH 9
2) Neutralophiles - Between pH 5-8
3) Acidophiles - Below pH 3
What are the classification parameters of microorganisms based on osmolarity?
1) Halophiles - Live in only high salt concentrations (require above 2 M of NaCl to survive)
2) Halotolerant - Can live in both high and low concentrations of salt (Can grow up to 2 M NaCl)
What are the classification parameters of microorganisms based on oxygen use?
1) Strict Aerobe - Can only live and reproduce with oxygen
2) Facultative Microbe - Can live and reproduce with and without oxygen
3) Microaerophile -Can live and reproduce with only very small levels of oxygen
4) Strict Anaerobe - Can only live and reproduce without oxygen
What are the classification parameters of microorganisms based on pressure?
1) Barophiles - Exist at pressures greater than 380 atm
2) Barotolerant - Exist at pressures between 10-500 atm
The domain Bacteria is considered the best studied Phyla. What are the different Phyla under this domain?
1) Oxygenic Phototrophs - Cyanobacteria
2) Gram-Positive - Firmicutes and Actinobacteria
3) Gram-Negative - Proteobacteria, Spirochetes, Bacteroidetes, and PVC Superphylum
What are the characteristics of cyanobacteria?
1) Oxygenic photoautotrophic prokaryotes (produce oxygen)
2) Contain chlorophyll and other pigments
What are the characteristics of Proteobacteria?
1) Divided into 5 major classes - Alpha-, beta-, gamma-, delta-, epsilon-
2) Contain a triple-layered Gram-negative cell envelope
3) Have a diverse metabolism
4) Have diverse lifestyles
True or False: Alphaproteobacteria are endosymbionts - Nitrogen fixers and plant roots (ex. Rhizobium)
True
True or False: Betaproteobacteria include many species that are pathogenic to humans and animals
False: It is Gammaproteobacteria that contain several pathogenic species.
What are the characteristics of Bacteroidetes?
1) Non-spore forming
2) Gram-negative
3) Contain aerobic and anaerobic species
4) Can be opportunistic pathogens (beneficial more often than not) to humans
5) Breaks down toxins in food
What are the Characteristics of Firmicutes?
1) Consists of large rod-shaped cells
2) Low-GC species
3) Bacillus and Clostridium species are able to form endospores (Staphylococcus and Streptococcus are non-spore forming)
True or False: Actinobacteria are low-GC species
False: They are high-GC species
Archaea contain many phyla. What is the most divergent phylum in Archaea?
Euryarchaeota
What are methanogens and what are their function?
They are made of pseudopeptidoglycan (most commonly), sulfated polysaccharides, or S-layer proteins. They produce methane that is trapped under oceans of permafrost deep underground.
What are the characteristics of Euryarchaeota?
1) Contain several polyphyletic clades of methanogens
2) Serve as a key energetic role for anaerobic removal of H2 and other reductants
3) Inhabit diverse environments
What are the charactersitics of Pyrococcus furiosus?
1) Live in deep-sea hydrothermal vents
2) Hyperthermophiles and barophiles
3) Thrives in 100°C conditions
4) Can metabolize sulfur into sulfuric acid (H2S)
5) An anaerobe
What are the uses of Archaea in Biotechnology?
1) Creating extremozymes - Enzymes with novel ranges in stability
2) Making vaccine adjuvants - An ingredient used to create a stronger immune response
3) Potential source of antibiotic classes being researched by the pharmaceutical industry
