Micro 205 exam 3 (CH 10 & 11)

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pH indicators

-Sugar fermentation lowers pH and may trap gas in inverted tube -Urease raises pH

Bdellovibrio species

Are highly motile gram negative curved rods Bore a hole in the cell wall of their prey Prey on gram negative bacteria like e. coli

the three-domain system

Bacteria, Archaea, Eukarya

________ species are Gram-negative, strictly anaerobic, make up about a third of the bacteria in fecal matter in humans, and are associated with abscesses and bloodstream infections.

Bacteroides

________ species are Gram-negative curved rods that are highly motile and prey on other Gram-negative rods by boring a hole in their cell wall.

Bdellovirbrio

Myxobacteria fulfill an important role in nature ______.

Can digest certain algae and fungi can digest bacteria are degraders or complex organic compounds

The cells of species in the genus Neisseria are ______.

Cocci usually in pairs Gram negative

Which of the following groups of bacteria is best described as a diverse group of photosynthetic Gram-negative bacteria that inhabit a wide range of environments?

Cyanobacteria

Campylobacter jejuni infections are commonly associated with ______.

Diarrhea

Taxonomic Hierarchy

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species(did king Phillip come over for great spaghetti)

During photosynthesis, anoxygenic phototrophs use _______ as a source of electrons to make reducing power.

H2S (hydrogen sulfide)

Medically-significant members of the genus Neisseria include?

N. gonorrhoaeae N. meningitidis

Gram-negative bacteria, that are typically kidney-bean-shaped cocci in pairs

Neisseria

Members of the genus are causative agents of gonorrhea and meningitis.

Neisseria

A diverse group of Gram-negative bacteria that obtain energy by oxidizing inorganic nitrogen compounds such as ammonium or nitrate are known as?

Nitrifiers

Many cyanobacteria can convert nitrogen gas (N2) to ammonia, which is a process called ______.

Nitrogen fixation

Nitrifiers can be described as bacteria that ______.

Obtain energy from inorganic nitrogen compounds (ex. ammonium or nitrite) Are gram negative

Cyanobacteria as a group are capable of ______.

Photosynthesis Nitrogen fixation

5 kingdom system based on morphological differences

Plantae, animilia, fungi, protista, prokaryotae

A viral species is defined by

Population of viruses with similar characteristics that occupies a particular ecological niche

Nitrogen fixation, or the process of converting nitrogen gas (N2) into ammonia, is an exclusive ability of ______. Multiple choice question.

Prokaryotes

Which of the following correctly describe relationships between genera of bacteria and their means for obtaining nutrients from plants?

Rhizobium species form a mutually benificial relationship with certain types of plants Agrobacterium species are plant pathogens that cause tumor like growth.

In a healthy individual, anaerobes can regularly be found on and in the ______

Skin Oral cavity Intestinal tract

You isolate an organism from the soil. If it turns out to be an aerobic Gram-positive rod that resembles a fungus in its pattern of growth, then it most likely belongs to the genus ______.

Streptomyces

Bacteria that oxidize sulfur are Gram-negative rods or spirals that ______.

Use sulfur compounds as an energy source and oxygen as a terminal electron receptor (sulfur oxidizing bacteria)

Strain

a sub-population of a species that share some properties absent in the rest of the group

Variant

a sub-population that contains a number of nucleotide changes, may/may not have any change in properties

In addition to being photosynthetic, many cyanobacteria have the ability to convert nitrogen gas (N2) into ______, a process known as nitrogen fixation.

ammonia

Which of the following were likely the earliest photosynthesizing organisms?

anoxygenic phototrophs

An organism found in an environment that is very hot and acidic is most likely a member of the domain

archaea

Characterized members of the domain ______ typically thrive in extreme environments, such as high heat, acidity, alkalinity, and salinity. Multiple choice question.

archaea

Certain bacteria that form symbiotic relationships with specific types of fish and squid are____, meaning they emit light.

bioluminescent

As a group, anaerobic chemoorganotrophs ______

can obtain energy via fermentation produce ATP via substrate level phosphorylation

A key characteristic of the genus Mycoplasma is that they lack a ____ _____, instead usually relying on sterols in their membrane to provide strength and rigidity.

cell wall

Serratia marcescens

colonies are typically red at 22 celcius

Facultative anaerobes can use aerobic respiration if O2 is present and ____ if O2 is not available.

fermentation

The genus Streptomyces includes more than 500 species that resemble ______ in their growth but are ______.

fungi; prokaryotes

The normal habitat of Bacteroides species in humans includes the ______.

genital tract intestines mouth

Extreme thermophiles are found near ______.

hot springs volcanic vents hydrothermal vents

Phylogenetics

infers evolutionary relationship among organisms by analyzing DNA sequences and/or other characteristics(DNA analysis is the most reliable way to classify a relationship between organisms)

Enterobacteriaceae get their name because they reside in the ______ tract of humans and animals.

intestinal

What makes eukaryotic Taxonomic Hierarcy different

it contains a subphylum

A group of Gram-negative bacteria that serve as an important model in the study of developmental biology because of their unique developmental cycle that includes the production of a fruiting body are the

myxobacteria

Aerobic chemoorganotrophs gain energy via the _______, using O2 as a terminal electron acceptor.

oxidization of organic compounds

Cyanobacteria are

photosynthetic gram-negative Morphologically diverse (range in shape from unicellular organisms to filamentous multicellular associations.)

Pseudomonas aeruginosa

produces green pigment and has a disting fruity odor

The _______ bacteria have projections called prosthecae, which are extensions of the cytoplasm and cell wall that increase the surface area to facilitate absorption of nutrients.

prosthecate

The purpose of the sheath in sheathed bacteria is for ______.

protection

By definition, obligate intracellular parasites cannot

replicate outside a host cell

Obligate aerobes obtain energy using _______ exclusively; none of them can ferment.

respiration

A group of Gram-negative bacteria has a spiral shape and a unique motility mechanism that allows them to move through thick, viscous substances. This group is called the

spirochetes

Which of the following bacteria is typically a harmless resident of the skin?

staphylococcus epidermis

Streptococcus pyogenes

strep throat- produces beta-hemolytic colonies on bloood agar

The motile cells found in sheathed bacteria are called ______ cells, and these exit through the end of the sheath.

swarmer

Bioluminescent bacteria are characterized by ______.

the ability to emit light

Humans infected with Helicobacter pylori may develop peptic____

ulcers

E. coli

urinary tract infection- ferments lactose, forms pink colonies on macconkey agar

Oxygenic phototrophs use ______ as a source of electrons for reducing power, generating O2. Multiple choice question.

water

Which of the following genera of endospore formers include both obligate aerobes and facultative anaerobes?

Bacillus

Antibiotics that interfere with peptidoglycan synthesis are ineffective in the treatment of _______ infections because these organisms lack a cell wall

mycoplasma

An organism that cannot reproduce outside of a host cell is termed an _____ ______ parasite.

obligate intracellular

Photoautotrophs

Organisms that use light as a source of energy to synthesize organic substances.(CO2-sugar). 2 types. - primary producer

molecular identification: Protein based tests vs. nucleic acid based tests

Protein based: - serology -protein profile Nucleic acids-based tests: - Hybridization -PCR -Sequencing

Which of the following taxonomic units have a higher a level and a lower level listed

The highest and lowest ones of the options given are the only ones that will not be selected.

How do we know if an infection comes from a common source?

We must identify the strain of the bacterium to conclusively say that.

Classification of microorganisms

What is the relationship amoung the micobes were looking at? - phenotypic traits(rarely used now) -Sequences or rRNA/rDNA, ribisomal protien genes, or even the entire genome(most commonly used now) -Dna composition and hybridization(rarely used now)

anaerobic chemoorganotrophs (chemoheterotrophs)

anaerobic respiration Oxidize organic compounds for energy sulfur/sulfate is their terminal electron acceptor form hydrogen sulfate They are sulfur/sulfate reducing bacteria

DNA sequences

analysis provides insight into evolutionary relationships between organisms and allows for phylogenetic tree construction.

genomic sequencing from metagenomic data

genomes are assembled from metagenomic data via a gene bank website. Gather info from a database and analyze it and this leads to the identification(in one study 8 new archeal Phyla and 14 new bacterial phyla)

extreme halophiles

grow in high salt concentrations(salt/soda lakes, and brines),require 9% Nacl but can grow in up to 32%, produce pigment(reddish), are aerobic/faculative areobic, chemoheterotrophs, various shapes ex: halobacterium, halorubrum natronobacterium, natronococcus

real depiction of phylogeny

network vs. two dimensional tree we are used to. Due to horizontal gene transfer.

What is the 3 domain system based on?

nucleotide sequences of ribisomal RNA (rRNA)

Extromophiles

thermus aquaticus- derives taq DNA polymeraser that is used in PCR, live in aquatic enviroments like hot springs thermotoga martima- also lives in aquatic enviroments( hot springs), contains some genome of archeal microbes

Nucleic acid based tests(genotype)

-DNA base composition - DNA fingerprinting -nucleic acid amplification test- PCR,LAMP,NASBA - Nucleic acid hybridization -Microarray chips -Sequencing (rRNA/other genes)

scientific name

genus + specific epithet, names are unique universal and meaningful

relationship between eukarya and archaea

most closly related domain

Taxanominc Endings Class Phylum subphylum order family

- ends in -tes -ends in -ota - ends in -cotina -ends in -ales -ends in -aceae

anoxygenic photoautotrophs

Earliest photosynthesizers use organic compounds(besides water) or h2s as electron sources and co2 as carbon source dio not produce oxygen -purple sulfur bacteria: perfer h2s, can live without light via oxidization of inorgaic/organic compunds, produce sulfur granules purple non sulfur bacteria: perfer orcanic sources for electron but can use h2 or h2s -green sulfur bacteria: strictly phototrophs and anerobes -filamentous bacteria: multicellular and thrive in hot springs

Anaerobic Chemoorganotrophs

fermentation glucose is their energy source pyrucate is their terminal electron acceptor produce lactic acid or ethanol EX. Clostridium(can be a pathogen), lactic acid bacteria(typically found in body. examples: streptococcus, lactococcus, lactobacillius- prevents vaginal yeast infection by maintaing pH balance), Propionibacterium(ferment lactic acid important in the making of cheese)

Methanogens often grow in association with

fermentative bacteria because they are both anaerobic bacteria

Aquatic bacteria

frequent environment changing, and changing nutrient amount that can be diluted, need to be able to fix themselves in one place. Examples: -Sheathed bacteria-can attach to a solid surface, form spores with flagella that allow them to find a new place in water (sphaerotilus) -Prosthecate bacteria- produce prostecat which is elongated cytopplasm of cell surface that allows for more nutrients to be absorbed(hypomycrobium- grow and then split off with newly formed flagella, caloubacter- has a 'hand' that can anchor bacteria to a solid surface, and they form flagella that allow them to swim away)

isolate

A sample obtained form an infected individual, a specific site, etc

Cyanobacteria living in aquatic environments can ______.

Accumulate in large numbers, which is known as a bloom Use gas vesicles to move vertically through a water column

Chemoorganotrophs that perform ______ often use sulfur or sulfate as a terminal electron acceptor

Anaerobic respiration

Most of the anaerobic chemolithotrophs that have been discovered are members of what domain?

Archea

Members of the family Enterobacteriaceae are _______.

gram negative rods

Endospore-forming bacteria are typically ______.

gram-positive rod shaped

Culture

grown in laboratory media

An organism that requires a minimum of 9% NaCl would be called an extreme

halophile

Prokaryotes that grow well in an environment that contains 32% NaCl would be called extreme

halophiles

Single-Cell Genomic Sequencing

sample is collected from an environment, and a single cell is separated into a tube via a cell sorter, the dna is then amplified to a sufficient amount via PCR, then assembled into a complete genomic sequence via a next generation sequencing machine. (in a single study this identified 44 bacterial phyla and 10 archeal phyla)

The most reliable indicator of evolutionary relatedness in prokaryotes

sequence of ribosomal components

microscopic morphology

Quickly determines size, shape, staining characteristics - gram stain, and other useful stains

Stereyotypes

a sub-population with the same antigenic properties

ch of the following can be used to distinguish between members of the genus Bacillus and Clostridium?

Their oxygen requirements

Mycobacterium species stain poorly because their cell walls contain ______.

Waxy lipids, A.K.A. mycolic acid

A eukaryotic species is defined by

a group of closely related organisms that breed amoung themselves

A prokaryotic species is defined as a

a population of cells with similar characteristics and inhibiting similar ecological niche (70% nucleic acid hybridization)

A special staining procedure called the ______ is used in the identification of Mycobacterium species.

acid-fast stain

Azotobacter species produce a resting cell called a(n) _________, that allows the organism to withstand drying and ultraviolet radiation

cyst

The resting cell produced by Azotobacter species that allows the organism to survive drying and ultraviolet radiation is called a(n) ______.

cyst

Biochemical tests

determines presence of bacterial enzymes

In this micrograph of stained bacterial cells, the structures forming in the mid-portion of the cells are called

endospores

Prosthecate bacteria form projections called prosthecae, which are extensions of the cytoplasm and cell wall. These prosthecae ______.

facilitate absorption of nutrients

An anaerobic chemoorganotroph that uses glucose for energy and pyruvate as its terminal electron acceptor is performing ____

fermentation

Taxanomy

the science of charicterize, name and arrange organism into groups

Scientists are interested in studying the growth of extreme _______,archaea that grow near volcanic vents and fissures because these conditions are thought to mimic early earth's environment.

thermophile

Sulfur-oxidizing bacteria

Are gram negative rods/spirals Oxidize sulfur/reduced sulfur compounds (ex. hydrogen sulfide and thiosulfate) Can sometimes grow in filaments

The two most common genera of Gram-positive rod-shaped bacteria that form endospores are ______.

Bacillus Clostridium

Hydrogen-oxidizing bacteria such as Aquifex and Hydrogenobacter are ______.

Gram negative Obligate chemolithotrophs thermophilic

Spirochetes are bacteria that are ______ and possess a unique mechanism of _______.

Gram negative; motility

Species of Campylobacter and Helicobacter are ______.

Microaerophilic Gram-negative curved rods

A reason why environments that are routinely exposed to O2 can support anaerobic growth is that ______.

O2 consuming organisms deplete oxygen levels

Of the various types of dormant cells, the ______ is the most resistant to environmental extremes.

endospore

Members of the Gram-negative genera Aquifex and Hydrogenobacter are hydrogen-oxidizing bacteria. An example of their metabolism involves using

hydrogen as an energy source, oxygen as an electron acceptor, and form water

Chemoorganotrophs oxidize _______ compounds such as glucose to obtain energy.

organic

As a group, chemolithotrophs ______ to obtain energy.

oxidize reduced inorganic compunds(such as hydrogen gas)

Bacteria that inhabit the skin

- Skin typically dry, salty; inhospitable to many microbes(typically gram +) - Staphylococcus are Gram-positive cocci- faculative anerobes, catalase positive, mostly harmless(S epidermis), many are medically important(pathogens: S. aureus- causes skin infections and can grow in food causing food poisoning. S. saprophyticus- causes UTIs)

Aerobic Chemolithotrophs- hyrdogen-oxidizing bacteria

- h2 energy source and o2 electron acceptor and produces water -gram negative thermophilic (some can grow in 95 celcius) - one of the earliest forms of bacteria - microaerophile: require a low level of oxygen -EX. aquifex, hydrogenobactera

Archeal microbes

- hyperthermophiles(pyrodictium-anaerobic, sulfur-reducing, disc shaped, pyrococcus-PCR, derives- pfu DNA polymerase) -extreme halophiles-require minimum of 9% of salt(halobacterium- ) -acidophiles(solfolobus- pH 2, 70 celcius.). Picrophilus- grow best below pH 1) -methanogens- methanobacterium- generate methane after oxidizing hydrogen as an energy source and using CO2 as a terminal electron acceptor.

Aerobic Chemolithotrophs- Sulfur oxidizing bacteria

-Gram-negative rods or spirals -Obtain energy through oxidation of sulfur/sulfur compounds -produces sulfuric acid -important to sulfur cycling -unicellular sulfur oxidizers: Acidothiobacillus- can drop surrounding pH to 1 -filamentous sulfur oxidizers: Beggiatoa- found in sulfur springs, sewage polluted waters, etc

nucleic acid hybridization with probes

-Southern hybridization(DNA) -Northern hybridization(RNA) Probes can be labeled with isotopes haptens or fluorochromes

faculative anaerobe chemoorganotrophs

-corynebacterium: gram+, club-, or v-shaped rods(C. diphtheriae causes diphtheria) -Enterobacteriaceae: Gram - rods, found in intestines, and sometimes soil, sometimes pathogens. Ferments glucose.peritrichous flagella if motile. Normal microbiota: Enterobacter, Klebsiella, Proteus, most E. coli strains. Pathogens: shigella, salmonella enterica, yersinia pestis, some E. coli strains - Vibrio: Gram -, found in Marin water, include the agent of cholera (V. cholerae), some are bioluminescent

extreme thermophiles

-methane generating hyperthermophiles: methanothermus-84-97 celcius. Methanophyrus kendlrei- can grow in 122 celcius -sulfur reducing hyperthermophiles: oxidize organics for energy and use S2 as terminal electron acceptor. pryolobus- 90-113 celcius. pyroditium-82-121 celcius -sulfur oxidizers- sulfolobus- grows in hot springs and produces sulfuric acids- pH2, 70 celcius -nanoarchea- nanoarchaeum equitans- parasite to other archea, 400 nm shpere

Aerobic Chemolithotrophs- nitrifiers

-oxidize inorganic nitrogen compunds for energy -oxygen as terminal electron acceptor -diverese gram negative -ammonium oxidizers: nitrosomonas, nitrosococcus - Nitrite oxidizers: nitrobacter, nitrococcus - If their waste is high in ammoniun then they will deplete water of o2 - useful in microbial food chain, their waste can be energy source

Aerobic Chemoorganotrophs

-oxidize organic compounds, use O2 as the final electron acceptor, generate some CO2 as waste product -large portion of bacteria, live in a variety of environments(ubiquitous) - some are obligate aerobes: cannot ferment -some are facultative anaerobes: can ferment if lack of o2 in the environment

2 methods of a urea test

1. breath test by testing the patience breath to see if it contains C2O. 2. A biochemical test conducted in the laboratory using a medium that contains urea and a pH indicator.

plant associated bacteria

Agrobacterium: G- rods, transfer DNA on Ti-plasmid to plant genomes, cause tumor and produce nutrients for themselves,opine. Rhizobium: G- rods, often fix nitrogen as do several related species, endosymbionts with plants, infect root hair of legumes and induce proliferation of cells that form nodules, provides fertilizer for plants and plant provides it nutrients Plant pathogens: Erwina, pectobacterium, pseudonomas, xanthomanos, liberbacter.

Photoheterotrophs

An organism that uses light to generate ATP but that must obtain carbon from an existing organic compound.

Anaerobic

Cannot grow in the presence of oxygen- likely were first bc earth's atmosphere did not used to have oxygen

Hybridization with a probe

DNA Microarrays -

Bioluminescent bacteria

Derive nutrients from other organisms, gram -, straight/curved rods, faculative anaerobes(aliivibro, photobacteria, vibro), the light is catalyzed from luciferase which is regulated by qurom sensing. at high concentrations the gene is transcribed, proteins are made and luminesence is produced, symbiotic- animal provide nutrients and bacteria help them to scare away predators, typically in deep sea animals.

metabolic diversity

Different ways a microbe can harvest energy to produce ATP

Protien profiling

Matrix assistid laser desorption ionization- time of flight-mass spectrometry- identifies common protein sequence in the sample, allows for easy bacteria identifiation- no longer common due to price and special equipment 1. Isolated colony and made her solution or attitude sample plate. 2. A laser beam converts the molecules in a sample to an ionized gaseous form. As the ions travel through the flight tube, they separate insured by mass. Detector records them as they arrive. 3. A mass spectrum is generated. Computer software then compares the profile with a reference database

Bacteria that inhabit mucous membranes

Moist, wet, has a lot of nutrients being secreted from the cell - Bacteroides species- gram-, rods or cocci, inhabit the mouth, intestinal tract, and genital tract, important for human digestion, require a lot of nutrients from humans to survive(1/3 of feces) - Bifidobacterium species-,gram -, aerobe, fastidious, coccobacillus reside primarily in the intestinal tract(B. pertussis- causes whooping cough) - Campylobacter and Helicobacter species are microaerophilic, Gram -, curved rods. (c, jejuni- causes diarrhea, H, pylori- causes ulcers, produces urease which neutralizes pH) - Haemophilus species found in blood - Neisseria species- gram -, paired cocci, in the oral cavity and genital tract, nutritionally fastidious, obligate aerobes - Treponema- gram -, spirochetes, inhabit mouth and genital tract, unculturable(T. pallidum causes syphilis) - Borrelia - gram -, spirochetes, inhabit mucous membranes, arthropod transmitted, linear chromosomes(B. burgdorferi-causes Lyme disease) - Mycoplasm- lacks cell wall(antibiotics for peptidoglycan synthesis are ineffective), very small, colony looks like fried eggs(m. pneumoniae- causes walking phenomena)

Why have a large amount of bacteria not been identified

They may be non culturable- may require special growth factors(nutients), may require a complex community and are reliant on the products of other bacterias, we do not know their physical/chemical conditions -note: New techniques, single cell genome sequencing and amplification of that genome or genome assembly from metagenomics sequences and next generation sequencing(low cost and accessible), have accelerated our ability to identify these unknown organisms

Human genomes

a composited of genes from various sources. 1/3 of genes are retrotransposons sequences. 47% of protein coding genes are from archaeal ancestors(used for information processing, DNA replication, RNA transcription, protein translation etc ), and about 53% of protein coding genes are from bacterial ancestors(essential for metabolic processes)

dichotomous key

a key for the identification of organisms based on a series of choices between alternative characters

Chemoautotrophs (AKA. chemolithotrophs)

can oxidize inorganic chemicals for an energy source(CO2 into sugar) - primary producers

Archea in extrme environments

can withstand: high heat, acidity, alkalinity, salinity. methanogens have exceptions many others are not found in extreme environments, but are not well characterized- detected via molecular techniques

culture characteristics

colony sizes colony color differential media aids in identification

Chemoheterotrophs

derive both carbon and energy from organic compound oxidization

Urea breath test

detects Helicobacter pylori

terrestrial environment

dry environment, microbes living in this environment have to be tough, typically gram +, able to survive unfavorable conditions(temperataure lack of nutrients etc.) examples: -Endospore bacteria- bacillus oblagate and faculative anaerobes(pathogen: Bacillus anthracis) , clostridium obligate anerobes(pathogens: C. botulinum,tetani, perfringes, difficle) - Myxobacteria- aerobic, gram - rods, groups of these form microcysts(dormant structure that allows for survival in unfavorable conditions), use organics and other microorganisms as food -Streptomyces-aerobic, gram +, form fungus like hyphae and conidia(dormant form with thick wall that can withstand dry environments), helps to produce many antibiotics, produce geosmin(rain smell, bc it releases gas)

predatory bacteria

live on other bacteria, - Bdellovibrio- gram - curved rods, often pray on E. coli, have a strong flagella, and secrete digestive enzymes to creat a hole in the bacteria they are latching to, live in the cell and secrete more digestive enzymes that digest away the cytoplasm of the host cell. THey grow, elongate, divide and by the time they finish digesting the host they grow flagella and leave.

Diversity of Prokaryotes

only 21,000 of estimated millions of species have been names and many bacteria have not been identified - metabolic(energy used) and ecophysiological(environment they live in) diversity

Anaerobic Chemolithotrophs

oxidize reduced inorganic chemicals to obtain energy. Use something other than oxygen as their terminal electron acceptor. (h2+co2-> ch4 2h2o) Were likely the first organisms on earth Mostly are Archaea EX. methanogens- most common found in swamps and digestive tracks of mammals, especially high in cows.

How do you rapidly test for a large variety of bacterial characteristics

rapid identification, commercial test kits

Aerobic

requires oxygen- evolved later

obligate intracellular parasites

small, gram - rods or coccobacilli, reduced genome size and needs nutrients to synthesize, - chlamydia- no peptidoglycan in cell wall, 2 forms: non infectious reticulate body and infection elementary body(c. trachomatis- urinary/vaginal infections, c. pneumoniae-phnemonia) -Anthropod transmitted pathogens: Rickettsia, Orientia, erhlichia -Wolbachia: parasites/mutulats of anthropods, and helminths(w. pipientis- kills embryos from mating with uninfected females- to ensure all progeny will be infected with the bacteria, kills male embroyo's, can change males to females)

oxygenic phototrophs

use light as their energy source, CO2 as a carbon source, and water as their electron source and produce sugar and oxygen cyanobacteria - earliest o2 producers/oxygenic phototrophs - many can fix nitrogen to ammonia via heterocysts that protect nitrogenase from oxygen - can be unicellular or multicellular (morphologically diverse) - plant chloroplasts evolved from their ancestors - can bloom from a lot of nutrients in their environment and can be toxic

Serilogical techniques

using antibodies to detect presence of specific molecules (proteins, polysaccharides, and nucleic acids) - targets: celll walls, capsules, flagella, etc techniques: -agglutination -Double immunodiffusion- not used often- forms parcipitate lines - Western blot: detects a specific protien and confirms size- uses protiens already seperated on a polyacrylamide gel -Enzyme-linked immunocorbent assay- allows processing of a large number of samples- uses a microtiter plate

obligate anaerobe chemoorganotrophs

variety of groups so just examples - micrococcus: gram+ cocci, yellow pigment, dry/salty conditions, can be airborne, found in soil dust and skin -mycobacterium: acid fact, pleomorphic rods, resistant to drugs(pathogens: m. tuberculosis, m. leprae) -Pseudomonas: Gram - rods, polar flagella, green pigment, fruity smell, metabollically diverse(pathogen:p. aeruginosa) -2 related genera: Thermus(gram-, thermophilic) and Deinococcus(gram+, radiation resistant)- both have unusual cell walls

The earliest oxygenic phototrophs probably belonged to a group of bacteria called ____

cyanobacteria


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