Microbio Final Exam

Crenarchaeota and Euryarchaeota

Bacteria and Eukarya

Euryarchaeota

chemotrophic energy metabolism

Respiration (citric acid cycle/TCA cycle) and oxidative phosphorylation occur here

Similar size to mitochondria, however, lacks TCA cycle enzymes and cristae. Oxidation of pyruvate to H2, CO2 and acetate

0.4 um and it contains one of the smallest genomes known

• 1. inhabit temperature extremes
• 2. most cultured representatives are hyperthermophiles
• 3. other representatives found in extreme cold environments

contains a membrane enclosed nucleus and several other organelles (mitochondria, golgi complex, peroxisomes, endoplasmic reticula, microtubules, and microfilaments)

Chlorophyll containing organelle found in phototrophic eukaryotes

Stroma

Large amounts of RubisCO

Calvin cycle

Stacks of membrane distinct from, but functioning in concert with, the ER. It modifies products of the ER destined for secretion.

• 1. Membrane enclosed compartments
• 2. Contain various digestive enzymes used for hydrolysis
• 3. Allow for lytic activity to occur within the cell without damaging other cellular components

Oxidize various compounds (alcohols, fatty acids, toxins) Also funtion in synthesis of bile salts.

Hyphae

Mycelia

Conidia

Heritable change in DNA sequence that can lead to a change in phenotype (observable properties of an organism)

A strain of any cell or virus differing from parental strain in geotype (nucleotide sequence of genome)

• 1. Mutations that cnage only one base pair
• 2. Can lead to single amino acid change in a protein or no change at all

Does not affect amino acid sequence

amino acid changed; polypeptide altered

codon becomes stop codon; polypeptide is incomplete

• 1. Deletions or insertions that result in a shift in the reading frame
• 2. Often result in complete loss of gene function

Strain in which original phenotype that was changed in the mutant is restored

Same-site revertant: mutation restoration activity is at the same site as original mutation

• Restriction enzymes
• Gel electrophoresis
• Nucleic acid hybridization
• Nucleic acid probes
• Molecular cloning
• Cloning vectors

recognize specific DNA sequences and cut DNA at those sites

• 1. They carry out anoxygenic photosynthesis; no oxygen evolved
• 2. Contain bacteriochlorophylls and carotenoid pigments

• 1. Most can grow aerobically in the dark as chemoorganotrophs
• 2. Some can also grow anaerobically in the dark using fermentative or anaerobic respiration
• 3. Most can grow photoheterotrophically

Most can grow autotrophically with H2 as sole electron donor and O2 as electron acceptor

• Straight or curved rods with polar flagella
• chemoorganotrophs
• obligate aerobes

Facultative aerobes

• Play important roles in production of buttermilk, silage, and other products
• Some species are pathogenic

genera of dairy significance

• generally found in soils
• endospores are advantageous for soil microorganisms

• Lack a respiratory chain, anaerobic
• Some clostridia perform stickland reactions
• Mainly found in anaerobic pockets in the soil
• Also live in mammalian intestinal tract
• Some are pathogenic; others cause diseases such as botulism, tetanus, and gangrene

metabolism of pair of amino acids

valuable for antibiotics and certain fermented dairy products

• first discovered in swiss cheese
• gram-positive anaerobes

• Over 500 species of streptomyces are recognized
• Streptomyces spores are called conidia
• Primarily soil microorganisms, responsible for earthy odor of soil (geosmins)
• Strict aerobes that produce many extracellular enzymes

• 50% of all isolated streptomyces produce antibiotics
• Over 500 distinct antibiotics produced by streptomyces

• Key genera: synechococcus, Oscillatoria, Nostoc
• Oxygenic phototrophs

• Budding bacterium
• Facultative aerobic chemoorganotroph
• Stalked
• Priarily aquatic
• Extensive cell compartmentalization including a membrane enclosed nuclear structure

gram-negative, motile, and tightly coiled

• Majority are human or animal pathogens
• Borrelia burgdorferi is the causative agent of Lyme disease

Borrelia burgdorferi

• Separates DNA molecules based on size
• Gels can be stained with ethidium bromide and DNA can be visualized under UV light

• recognize specific DNA sequences and cut DNA at those sites
• Essential for in vitro DNA manipulation
• Sticky ends or blunt ends

Ethidium bromide

Base pairing of single strands of DNA or RNA from two different sources to give a hybrid double helix

Segment of single stranded DNA that is used in hybridization and has a predetermined identity

Hybridization procedure where DNA is in the gel and probe is RNA or DNA

isolation and incorporation of a piece of DNA into a vector so it can replicated and manipulated

Plasmids or viruses

in vitro

• enzyme that joins two DNA molecules
• works with sticky or blunt ends

• Performed in vitro and introduces mutations at a precise location
• can be used to assess the activity of specific amino acids in a protein
• Structural biologists have gained significant insight using this tool

encode proteins that are easy to detect and assay

promoters or coding sequences of genes of interest can be swapped with those of reporter genes to elucidate gene regulation under various conditions

plasmids are natural vectors and have useful properties as cloning vectors

• common cloning vector
• contains ampicillin resistance and lacZ gene
• contains polylinker (multiple cloning site) within lacZ gene

blue colonies do not have vector with foreign DNA inserted

White colonies have foreign DNA inserted

• LacZ gene is inactivated by insertion of foreign DNA
• inactivated lacZ cannot process Xgal; blue color does not develop