BIS 2C Lecture Notes - Lecture 9: Blood Falls, Rhizobium, Anaerobic Organism
27 Apr 2018
School
Department
Course
Case Study of Blood Falls, Antarctica
Dry valleys used as a place to study how life might be in other planets
•
Has isolated marine systems of salt water under the snow in the rock bed
•
Red because of iron oxide that seeps through the snow
•
17 kinds of bacteria and archaea that used sulfur and iron to survive
•
Functional Diversity of Prokaryotes
Anaerobic vs Aerobic
Aerobes: use oxygen
○
Anaerobes: don't used
Facultative Anaerobes: shift between both aerobic and anaerobic
§
Obligate Anaerobes: oxygen is toxic
§
Aero-tolerant Anaerobes: don't use oxygen but not harmed by it
§
○
•
Energy used
Photoautotrophs: energy source is light, carbon source is carbon dioxide
Some bacteria and eukaryotes
§
○
Photoheterotrophs: energy source is light, carbon source are organic
compounds
Some bacteria
§
○
Chemoautotrophs: use inorganic substances as energy source, carbon source is
carbon dioxide
Some bacteria but mostly archaea
§
○
Chemoheterotrophs: energy from organic (some inorganic) compounds,
carbon source are organic compounds
Found in all three domains
§
○
•
Importance to ecosystems
Primary productivity affected by Photosynthesis via plants and microbes
Aid plants in nutrient uptake and water uptake
Rhizobium bacteria help with getting nitrogen fixed from the atmosphere
§
○
•
Affect global nutrient cycles system by affecting the fixation and concentration of the
main atmospheric compounds and environmental nutrients
•
Extremophiles
Microbes that live in extreme environments
Relative to average environmental conditions such as temperature (thermophile),
absence of oxygen(anaerobe), high pressure at bottom of ocean, radiation
○
•
Thermophile adaptations (found throughout bacteria archaea)
Stress of heat
causes protein, DNA, RNA denaturation
§
Chemical reactions speed up
§
Membranes liquefy
§
○
Adaptations
More stable proteins with altered amino acids, more salt bridges
§
Slowing enzyme rates
§
Decrease fluidity of membrane
§
○
•
Convergence of Extremophily
Some adaptations require changes made in most or all genes of genome (like being
a thermophile)
So if you see distant groups with that type of adaptation then it's usually
because of convergent evolution
§
○
Other adaptations just need to have certain metabolic processes (antibiotic
resistance)
If seen in distant groups, then result of LGT or convergent evolution
§
○
•
Industrialization of Extremophiles
Thermus aquaticus
PCR - use Taq polymerase to stand through high temperature requirement while
shocking and annealing DNA strands while amplifying the number of strands.
○
•
Culturing
Culturing is the growth of microorganisms in controlled conditions
•
Pure culture is one in which only one type of microbe is present
•
Most prokaryotes can't be/haven't been cultured
•
Identifying Uncultivable Microbes
Take samples
•
Extract DNA
Barcoding a specific section to find similarities and differences
○
Metagenomic process: Entire genomic sequencing
○
•
Microbes to Know
Firmicutes
Most gram positive
○
Many agents of disease like staph, streptococcus
○
Some have no cell wall
○
•
Cyanobacteria
Gram negative
○
Phototautotrophic with chlorophyll a
○
Chloroplasts derived from endosymbiotic cyanobacteria
○
Heterocysts specialized for nitrogen fixation
○
•
Proteobacteria
Largest group of bacteria
○
Gram-negative
○
Mitochondria derived from endosymbiotic proteobacteria
○
Coli is an example
○
Archaea have lipid monolayer
○
•
Bis2C
Prokaryote…
Outline Lect
9 2016
Prokaryote Biology and Diversity (9)
Tuesday, January 23, 2018
6:06 PM
Case Study of Blood Falls, Antarctica
Dry valleys used as a place to study how life might be in other planets
•
Has isolated marine systems of salt water under the snow in the rock bed
•
Red because of iron oxide that seeps through the snow
•
17 kinds of bacteria and archaea that used sulfur and iron to survive
•
Functional Diversity of Prokaryotes
Anaerobic vs Aerobic
Aerobes: use oxygen
○
Anaerobes: don't used
Facultative Anaerobes: shift between both aerobic and anaerobic
§
Obligate Anaerobes: oxygen is toxic
§
Aero-tolerant Anaerobes: don't use oxygen but not harmed by it
§
○
•
Energy used
Photoautotrophs: energy source is light, carbon source is carbon dioxide
Some bacteria and eukaryotes
§
○
Photoheterotrophs: energy source is light, carbon source are organic
compounds
Some bacteria
§
○
Chemoautotrophs: use inorganic substances as energy source, carbon source is
carbon dioxide
Some bacteria but mostly archaea
§
○
Chemoheterotrophs: energy from organic (some inorganic) compounds,
carbon source are organic compounds
Found in all three domains
§
○
•
Importance to ecosystems
Primary productivity affected by Photosynthesis via plants and microbes
Aid plants in nutrient uptake and water uptake
Rhizobium bacteria help with getting nitrogen fixed from the atmosphere
§
○
•
Affect global nutrient cycles system by affecting the fixation and concentration of the
main atmospheric compounds and environmental nutrients
•
Extremophiles
Microbes that live in extreme environments
Relative to average environmental conditions such as temperature (thermophile),
absence of oxygen(anaerobe), high pressure at bottom of ocean, radiation
○
•
Thermophile adaptations (found throughout bacteria archaea)
Stress of heat
causes protein, DNA, RNA denaturation
§
Chemical reactions speed up
§
Membranes liquefy
§
○
Adaptations
More stable proteins with altered amino acids, more salt bridges
§
Slowing enzyme rates
§
Decrease fluidity of membrane
§
○
•
Convergence of Extremophily
Some adaptations require changes made in most or all genes of genome (like being
a thermophile)
So if you see distant groups with that type of adaptation then it's usually
because of convergent evolution
§
○
Other adaptations just need to have certain metabolic processes (antibiotic
resistance)
If seen in distant groups, then result of LGT or convergent evolution
§
○
•
Industrialization of Extremophiles
Thermus aquaticus
PCR - use Taq polymerase to stand through high temperature requirement while
shocking and annealing DNA strands while amplifying the number of strands.
○
•
Culturing
Culturing is the growth of microorganisms in controlled conditions
•
Pure culture is one in which only one type of microbe is present
•
Most prokaryotes can't be/haven't been cultured
•
Identifying Uncultivable Microbes
Take samples
•
Extract DNA
Barcoding a specific section to find similarities and differences
○
Metagenomic process: Entire genomic sequencing
○
•
Microbes to Know
Firmicutes
Most gram positive
○
Many agents of disease like staph, streptococcus
○
Some have no cell wall
○
•
Cyanobacteria
Gram negative
○
Phototautotrophic with chlorophyll a
○
Chloroplasts derived from endosymbiotic cyanobacteria
○
Heterocysts specialized for nitrogen fixation
○
•
Proteobacteria
Largest group of bacteria
○
Gram-negative
○
Mitochondria derived from endosymbiotic proteobacteria
○
Coli is an example
○
Archaea have lipid monolayer
○
•
Bis2C
Prokaryote…
Outline Lect
9 2016
Prokaryote Biology and Diversity (9)
Tuesday, January 23, 2018
6:06 PM
