Lecture 10 Flashcards
HD
Includes most of the Gram negative, chemoheterotrophic bacteria.
Proteobacteria
Proteobacteria are presumed to have arisen from a common ________ _________
photosynthetic ancestor
What has replaced proteobacteria’s photosynthetic characteristics?
Metabolic and nutritional capacities.
The largest taxonomic group of bacteria
proteobacteria
They are commonly described as filamentous bacteria, which resemble that of the filamentous fungi.
Actinomycetes, Ipek’s favourite bacteria
If a bacteria has branched hyphae or branching filaments does that means it is classified as a actinomycete?
No
Very common in soil where a filamentous pattern of growth has advantages.
Actinomycetes
Can bridge water-free gaps between soil particles to move to a nutritional site. This morphology also gives the organism a much higher surface-to-volume ratio and improves its nutritional efficiency in the highly competitive soil environment.
Actinomycetes
the best known and most studied of the actinomycetes, and one of the bacteria most commonly isolated from soil.
Streptomyces
What are the reproductive asexual spores of Streptomyces are called?
conidiospores
Are Streptomyces strictly aerobic or anaerobic
aerobic
Often produce extracellular enzymes that enable them to utilize proteins; polysaccharides, such as starch; cellulose, and many other organic materials found in soil.
Steptomyces
Streptomyces characteristically produce a gaseous compound called _______, which gives fresh soil its typical musty odor.
geosmin
The production of what has led to the study of streptomyces?
Antibiotics
In some studies what percentage of streptomyces have been proven to be antibiotic producers?
50%
Can Streptomyces produce more that one kind of antibiotic by one organism. Do they have to be chemically related?
Yes and no
Comprise a large and morphologically heterogenous group of phototorophic bacteria
Cyanobacteria
What species have a unique developmental cycle that is perhaps their most distinguishing characteristics.
Chlamydia
Are chlamydia gram-negative or positive
gram-negative coccoid bacteria
What is the infective agent of chlymydia?
It’s Elementary body
Unique stalked bacterium found in aquatic environments.
Planctomyces/Pirella
This phylum of bacteria derives from Greek roots meaning “warty” due to the multiple projecting prosthecae. Stalked bacteria in this group attach to particulate matter, plant material, and other microrganisms in aquatic habitats. This action also increases the surface to volume ratio of the cells.
Verrucomicrobia - think warty a warty Vera
This kingdom of bacteria contains a mixture of physiological types ranging from obligate aerobes to obligate anaerobes inhabiting in many different environments.
Flavobacteria
Members of this genus are long, slender rods, often with pointed ends, that move by gliding.
Cytophaga
This genus produce diseases that preferentially affect stressed fish, such as those living in waters receiving pollutant discharges or living in high-density confinement situations such as fish hatcheries and aquaculture operations. Infected fish show tissue destruction, frequently around the gills
Cytophaga - fish infector
What are the 2 diseases caused by cytophaga that affect these stressed fish.
columnaris caused by C.columnaris and cold-water disease caused by C.psychorphia
This bacteria are phylogenetically distinct group of non-motile anoxygenic phototrophic bacteria that contain only obligately anaerobic and phototrophic species. Like purple sulfur bacteria, green sulfur bacteria live in anoxic aquatic environments, especially where H2S is abundant
Green sulfur bacteria
Certain green-sulfur bacteria can form a tight two-member-association with chemoorganotrophic bacterium in which each organism benefits the other; such associations are called what?
consortia.
Gram-negative, motile, tightly coiled bacteria, typically slender and flexuous in shape.
Spirochetes
produces Taq DNA polymerase that is a heat stable enzyme used in PCR for the amplification of DNA.
Thermus aquaticus
The best-studied genera of the kingdom Deinococci
Deinococcus radiodurans
Is Deinococcus gram-negative or positive?
Positive
Most deinococci strains are highly resistant to ________ and _________ and ________
UV and desiccation and raditation
resistant to the mutagenic effects of many other mutagenic agents.
Deinococcus radiodurans
have been isolated from near atomic reactors and other potentially lethal radiation sources.
Deinococcus radiodurans
Powerful DNA repair machinery exists in __________ cells that are able to repair the organism’s chromosome, even from a fragmented state.
Deinococcus
This phylum of bacteria is phylogenetically distinct and contains just a few genera. Thermomicrobium is a member of this group and is strictly aerobic, Gram-negative rod, growing optimally in complex media at 75°C.
Green Non-sulfur Bacteria
These bacteria are filamentous prokaryotes that form thick microbial mats in neutral to alkaline hot springs as well as in non-thermal marine microbial mats
Chloroflexus and most other green nonsulfur bacteria
The key physiological feature of most of them is hyperthermophily, that is, optimal growth at temperatures above 80°C.
Deeply Branching Hyperthermophilic Bacteria
This bacteria is a rod-shaped hyperthermophile capable of growth to 90°C and are isolated from terrestrial hot springs as well as marine hydrothermal vents
Thermotoga
Physiologically, these organisms are either chemolithotrophs or chemoorganotrophs, and are mesophilies to thermophiles.
Nitrospira and Deferribacter
What are the 5 major phyla of Archaea?
Euryarchaeota, Nanoarchaeota, Korarchaeota, Crenarchaeota ,Thaumarchaeota
Among cultured representatives, the ____________ contain mostly hyperthermophilic species including those able to grow at the highest temperatures of all known organisms. Many hyperthermophiles are chemolithotrophic autotrophs, and because of their habitats are devoid of photosynthetic life, these organisms are thus the only primary producers in these harsh environments.
Crenarchaeaota
Such hot sulfur rich environments are called _________, and are found throughout the world (Italy, Iceland, NZ and Wyoming National Park in the USA). Hyperthermophilic Crenarchaeaota also thrive in undersea hot springs called _________ ______
solfataras, hydrothermal vents.
In contrast with the Hyperthermophiles, cold-dwelling Crenarchaeaotes have been identified from community sampling of ______ _______ from many non-thermal environments.
rRNA genes
In stark contrast to the Hyperthermophiles, cold dwelling Crenarchaeaotes can thrive in frigid waters, such as those of Antarctica. These organisms are __________(suspended freely or attached to suspended particles in the column) and occur in waters that are nutrient poor and very cold.
planktonic
Two examples of crenarchaeaotes found in trrrestrial volcanic habitats are
Sulfolobales and Thermoproteales
On example of crenarchaeaotes found from submarine volcanic habitats is
Dessulfurococcales
Euryarchaeaotes - Marine salterns are also habitats for extremely ________ _________. Marine salterns are small-enclosed basins filled with seawater that are left to evaporate, yielding NACl and other salts of commercial value.
halophilic prokaryotes.
The term extreme halophile is used to indicate not only that these organisms are halophilic, but also …..
their requirement for salt is very high (12-23%).
The extremely halophilic Archaea are frequently referred to collectively as ___________, because the genus Halobacterium was the first in this group to be described
“halobacteria”.
A large number of Euyarchaeatoa produce methane as an integral part of their energy metabolism. Such organisms are called ___________
methanogens
_____________is the terminal step in the biodegradation of organic matter in many anoxic habitats in nature such as swamps.
Methanogenesis
A phylogentically distinct line of Archaea contains two thermophilic and extremely acidophilic prokaryotes, which are called __________ and _________
Thermoplasma and Picrophilus.
Thermoplasma and Picrophilus are organisms that are among the most acidophilic of all known prokaryotes and, in the case of Picrophilus, even capable of growth below pH ____.
- as low as -0.06. Two species of this genus have been isolated from acidic Japanese solfataras.
is a chemoorganotroph and grows optimally at 55°C and pH 2.
Thermoplasma
Most strains of __________ were isolated from self-heating coal refuse piles. __________ species metabolizes organic compounds leached from the hot coal refuse.
Thermoplasma, thermoplasma
At moderately acidic pH the membranes of cells of Picrophilus quickly become ________ and literally ________, clearly indicating that this organism has evolved to survive only in highly acidic habitats.
leaky, disintegrate
A few Euryarchaeaotes thrive in thermal environments and some are extremely thermophilic; those with growth temperature optima over 80°C are called
hyperthermophiles.
3 Key genera of hyperthermophilic Euryarchaeota
Thermococcus, Pyrococcus, and Methanopyrus
___________ was isolated from hot marine sediments near hydrothermal vents and couples the oxidation of H2, lactate, pyruvate, glucose, or complex organic compounds to the reduction of sulfate to sulfide.
Archaeaoglobus
__________is not a sulfate-reducing bacterium; instead it is an iron-oxidizing chemolithotrophic autotroph, conserving energy from the oxidation of iron.
Ferroglobus
