Microbiology: Chapter 11

50 terms by firefly1145

Create a new folder

Advertisement Upgrade to remove ads

Exam 2: Bacteria types

Proteobacteria

most of the gram-negative, chemoheterotrophic bacteria, presumed to come from common photosynthetic ancestor, name comes from Greek god Proteus who could assume many shapes

Alphaproteobacteria

most are capable of growth at very low levels of nutrients, unusual morphology: protrusions such as stalks and buds called prosthecae, agriculturally important due to nitrogen fixation in symbiosis with plants, plant and animal pathogens

Rickettsia

Alphaproteobacteria
Obligate intracellular parasites: reproduce only within a mammalian cell, gram-negative, rod-shaped, transmitted to humans through bites of insects and ticks
Damage permeability of human capillaries: cause rashes

Rickettsia prowazekii

epidemic typhus from lice

Rickettsia typhi

endemic murine typhus from rat fleas

Rickettsia rickettsii

Rocky mountain spotted fever from ticks

Rhizobia

Alphaproteobacteria
Includes Rhizobium and Bradyrhizobium
Infect the roots of leguminous plants (beans, peas, or clover)
Formation of nodules on the plant
Symbiotic relationship: bacteria fixes nitrogen from air for plant to use

Agrobacteria

Alphaproteobacteria
ability to invade plants
No nitrogen fixation, does not invade roots

Agrobacterium temfaciens

Causes crown gall in plants where roots and stem merge
inserts a plasmid that contains genetic information into the plant's chromosomal DNA

Betaproteobacteria

Use nutrient substances that diffuse away from areas of anaerobic decomposition of organic matter: hydrogen gas, ammonia, and methane
Several pathogenic bacteria

Spirillum

Betaproteobacteria
Mainly in fresh water
motile by conventional polar flagella
Relatively large, gram-negative, aerobic bacteria

Burkholderia

Betaproteobacteria
motile by a single polar flagellum or tuft of flagella

Burkholderia cepacia

Best known species of burkholderia
aerobic, gram-negative rod
Large nutritional spectrum and can degrade over 100 organic molecules
Contamination of equipment and drugs in hospitals
Can grow in disinfectant solutions
Metabolizes secretions in patients with cystic fibrosis

Bordetella

Betaproteobacteria

Bordetella pertussis

nonmotile, aerobic, gram-negative rod
Cause of whopping cough or pertussis

Neisseria

Betaproteobacteria
aerobic, gram-negative cocci
Inhabit mucous membranes of mammals

Neisseria gonorrhoeae

Causes gonorrhea

Neisseria meningitidis

Causes meningococcal meningitis

Gammaproteobacteria

Largest subgroup of proetobacteria

Pseudomonas

Gammaproteobacteria
Pseudomonadales
Aerobic, gram-negative rods
Motile by polar flagella: single or tufts
Many excrete extracellular, water-soluble pigments that diffuse into their media
Can grow on minute traces of carbon sources such as soap residue and cap-liner adhesives
People with cystic fibrosis are susceptible
Have as much genetic capacity as the eukaryotic yeasts and half as the fruit fly

Pseudomonas aeruginosa

Pseudomonadales
Can cause infection of the urinary tract, burns, and wounds, and can cause blood infections

Azotobacter

Gammaproteobacteria
Pseudomonadales
Nitrogen fixing bacteria
Free living in soil
Large, heavily capsulated

Azomonas

Gammaproteobacteria
Pseudomonadales
Nitrogen fixing bacteria
Free living in soil
Large, heavily capsulated

Legionellales

Gammaproteobacteria
Previously considered rickettsial
Readily grow on suitable artificial media

Legionella

Gammaproteobacteria
Legionellales
Cause of an outbreak of pneumonia
Common in streams
Colonize habitats such as warm-water supply lines in hospitals and water in the cooling towers of air conditioning systems

Coxiella

Gammaproteobacteria
Legionellales
Coxiella burnetii: responsible for Q fever
Need a mammalian host to reproduce
Not transmitted through insect or tick bites
Most commonly transmitted through aerosols or contaminated milk
High resistance to the stresses of airborne transmission and heat transmission

Vibrio

Gammaproteobacteria
Legionellales
Slightly curved rods
Usually inhabit coastal salt waters
Transmitted usually by raw or undercooked fish

Vibrio cholerae

Gammaproteobacteria
Legionellales
Causes cholera

Enterobacteriales

Gammaproteobacteria
Facultatively anaerobic, gram-negative rods
Peritrichously flagellated if motile
Inhabit the intestinal tracts of humans and other animals
Fimbriae that help them to adhere to surfaces or mucous membranes
Sex pili for reproduction: help to transfer bacteria resistance
Produce bacteriocins that cause the lysis of related bacteria, which may help maintain the ecological balance in the intestines

Enterics

Another word used to reference the bacterial group Enterobacteriales
Intestinal tracts

Escherichia

Gammaproteobacteria
Enterobacteriales
Escherichia coli: most common inhabitants in human intestinal tract, also very useful in the laboratory

Salmonella

Gammaproteobacteria
Enterobacteriales
Almost all are potentially pathogenic
Common inhabitants of the intestinal tract
Often divided into several serovars/serotypes: serological varieties

Shigella

Gammaproteobacteria
Enterobacteriales
Responsible for bacillary dysentery or shigellosis
Found only in humans
Some cause life-thretening dyssentery

Klebsiella

Gammaproteobacteria
Enterobacteriales
Commonly found in soil or water
Fix nitrogen from the atmosphere which could be a nutritional advantage
Causes a serious form of pneumonia in humans

Serratia

Gammaproteobacteria
Enterobacteriales
Production of red pigment
Probably the cause of many urinary and respiratory infections in hospitals

Proteus

Gammaproteobacteria
Enterobacteriales
Swarming type of growth
swarmer cells have flagella ,move to outside of colony, then resort to normal growth
In urinary tract and wounds

Yersinia

Gammaproteobacteria
Enterobacteriales
Yersinia pestis: causes plague, Black death in Europe
Fleas transmit the disease

Erwinia

Gammaproteobacteria
Enterobacteriales
Primarily plant pathogens
Produce enzymes the hydrolyze the pectin between plant cells that causes plant cells to separate: plant rot

Enterobacter

Gammaproteobacteria
Enterobacteriales
Cause urinary tract infections
widely distributed in humans and animals and water, sewage, and soil

Pasteurellales

Gammaproteobacteria
Non motile
Best known as human and animal pathogens

Haemophilus

Gammaproteobacteria
Pasteurellales
X factor: heme fraction: need blood for respiration
V factor: NAD+ or NADP+: cofactor also needed from media for respiration

Deltaproteobacteria

Include some bacteria that are predators on other bacteria

Bdellovibrio

Deltaproteobacteria
attacks other gram-negative bacteria
Attaches tightly and reproduces in the periplasma
Cell elongates and the cell lyses releasing the bacteria

Desulfovibrionales

Deltaproteobacteria
Sulfur reducing bacteria
Use oxidized forms of sulfur instead of oxygen

Epsilonproteobacteria

slender, gram-negative rods
Helical or curved

Campylobacter

Epsilonproteobacteria
Each cell has one polar flagellum
Can cause spontaneous abortion
Leading cause of outbreaks of foodborne intestinal disease

Helicobacter

Epsilonproteobacteria
Microaerophilic curved rods with multiple flagella
Cause peptic ulcers in humans

Two groups of Gram-positive bacteria

Firmicutes (low G + C ratios)
Actinobacteria (high G + C ratios)

Firmicutes

Low G + C ratio
Includes important endospore-forming bacteria
Mycoplasma also found in this phylum, although they do not have a cell wall

Clostridium

Firmicutes
Clostridiales
Obligate anaerobes
Rod-shaped cells
Contain endospores that usually distend the cell
Endospore: resistant to heat and many chemicals

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set