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- author "Shughesi "
- tags "Mirco Exam 2"
- description "The Proteobacteria"
- fileName "Bergey's Manual Vol 2 "
- freezingBlueDBID -1.0
- Phylum Proteobacteria
- Known as the Purple bacteria
- - Gram Negative.
- - Large and extremely complex group that over 1300 species in over 400 genera.
- - diverse in morphology, physiology, and lifestyle.
- - phototrophy, heterotrophy, and chemolithotrophy.
- - divided into 5 classes based on rRNA data.
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Class Alphaproteobacteria
- The first class of Phylum Proteobacteria.
- Contains Orders Rhodospirillum, Rickettsiales, and Rhizobiales.
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Genus Rhodospirillum
- In Order Rhodospirillum
- Ex. of the purple nonsulfur bacteria.
- Normally grow aerobically as photoorganoheterotrophs.
- Or grow aerobically as chemoorganoheterotrophs.
- Most prevalent in the mud and water of lakes and ponds with abundant organic matter
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Order Rickettsiales
- Part of Class I Alphaproteobacteria
- Obligate parasites
- Assoicated with the mononuclear phagocyte system and vascular endothelial cells
- May cause disease in humans or in vertebrate and invertebrate hosts.
- Mutualistic relationships b/t some insects and some rickettsias in which rickettsias provides factors essentials for the insects growth and reproduction.
- Cells are rod shape or coccoid.
- Often pleomorphic.
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Genus Rickettsia
- Part of order Rickettsiales in Class Alphaproteobacteria
- Growth occurs in the cytoplasm.
- Sometimes in the nucleus of certain vertebrate and arthropod cells
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Genus Ehrlichia
- In Order Rickettsiales in Class Alphaproteobacteria
- Transmitted by tick vectors
- 1986: 1st case of human monocytic erhlichiosis (HME) in the Western Hemisphere.
- 1994: new form called human granlocytic ehrlichiosis (HGE).
- Its symptoms similar to Rocky Mountain Spotted Fever except there is no rash with erhlichiosis.
- Symptoms also include leucopenia and thrombocytopenia.
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Genus Rhizobium
- Class Alphaproteobacteria Order Rhiobiales
- Symbiotic nitrogen fixation
- Bacteria induce the formation of nodules on the roots of leguminous plants and convert N2 gas to N3.
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Genus Agrobacterium
- Class Alphaproteobacteria Order Rhizobiales
- Do not fix N2
- Plant pathogens that cause tumors on the crown, roots, and stems of dicots.
- Tumor production is determined by the presence of a plasmid: Tumor inducing plasmid (TIP).
- May be modified with the insertion of desirable genes for use in genetic engineering of plants.
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Genus Bartonella
- Class Alphoproteobacteria Order Rhizobiales
- Has two species:
- Bartonella quintana
- Causes trench fever or shinbone fever.
- Symptoms are mild, primarily fever associated with pains in the shins; louse borne.
- Reappeared in homeless populations and causing endocarditis.
- Can be cultivated in vitro on a cell0free media (blood agar), in vivo it grows epicellularly.
Bartonella henselae- cat scratch disease: malaise, fever, lymphadenopathy.
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Genus Brucella
- Class Alphoproteobacteria Order Rhizobiales
- Very short rods, nonmotile, causative agent of brucellosis (Malta fever).
- Disease found in cattle, goats, swine, sheep, and bison.
- Zoonosis, less than 200 human causes a year in the U.S.
- Causes undulating fever, enlarged spleen, and lymph nodes, muscle aches, and death by endocarditis.
- Potential biological warfare agent by aerosol route.
- From consumption of unpasterized milk, abattoir (slaughterhouse), and veterinary work.
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Class II Betaproteobacteria
Has Genus Burkholderia, Bordetella, and Neisseria.
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Genus Burkholderia
- Class II Betaproteobacteria
- Has two species:
- Burkholderia cepacia: causes sour skind of onion and causes nosocomial infections.
- A problem of cystic fibrosis.
Buckholderia solanacearum: cause of bacterial Wilt of Tomatoes.
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Genus Bordetella
- Class II Betaproteobacteria
- Bordelleta
pertussis: short rods. - Found only in the repiratory tract of humans
- Cause of whooping cough or pertussis that is primarily a childhood disease (500,000 die each year.)
- Less thatn 10 in the U.S.
- Results in secretion of thick mucous in the upper repiratory tract and prolonged coughing sieges of 5 to 15 rapidly consecutive coughs followed by a whoop.
- Prevention is with the DTP or DTaP vaccine that is given at 2, 4, 6, and 18 months and repeated at 4 or 5 years.
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Genus Neisseria
- Class II Betaprobacteria Order Neisseriales
- cocci occuring singley by more often in pairs with adjacent sides flattened.
- Inhabitants of mucous membraes of mammals
- Two species highly pathogenic for humans: Neisseria gonorrheae and Neisseria meningitidis.
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Class III Gammaproteobacteria
- Consitutes the largest subgroup of proteobacteria.
- Contains Genus:
- Chromatium,
- Francisella,
- Legionella,
- Coxiella,
- Pseudomonas,
- Acinetobacter,
- Vibrio,
- Photobacterium
- Salmonella,
- Erwinia,
- Yersinia, and
- Haemophilus
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Genus Chromatium
- Class III Gammaproteobacteria Order Chromatiales
- Rod shaped or ovoid cells with rounded ends
- Motile by polar flagella
- Contain internal vesicular photosynthetic members.
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Genus Francisella
- Class III Gammaproteobacteria Order Thiotrichales
- Contains species: Francsiella tularensis
- Small rods and zoonosis
- Endemic in the U.S. in wild animals such as rabbits, squirrels, deer, and birds.
- Cause of rabbit fever or tularemia.
- Transmitted to humans by bites of ticks and deer flies.
- Hunters who skin infected rabbits can acquire the organism.
- Symptoms can include high fever of 104 - 106F, enlarged lymph nodes (buboes), and an unlcer may form at the site of entry.
- Possible bioterrorism agent.
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Genus Legionella
- Class Gammaproteobacteria Order Legionellales
- Species: Legionella pneumophila
- Cause of Legionnaires' Disease named following an outbreak of veterans who attended an American Legion convention in July 1976 in Philly.
- Small Gram Negative bacteria.
- Grows in H2O associated with amaebas on an interacellular parasite.
- Found in the A/C system, shower heads, and misters.
- Does not transmit to human to human.
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Genus Coxiella
- Gamma Betaproteobacteria Order Legionellales
- Coxiella burnetiiCause of Query or Q fever which is a type of pneumonia.
- Grows in the phagolysosmones of the host cell.
- High resistance to chemical agents & elevated temperatures.
- Can survive 143F for 30 mins.
- Resistance is due to endospore-like stucture in the large cell variant.
- WW distribution of invertebrate/ vertebrate host: cattle, sheep, and goats.
- Infection in humans happen by aerosol routes: inhaling infectious dust from tick fees deposited on the hides of animals and from the dried placenta of animals giving birth. Also from drinking unpasteurized milk.
- Biological warfare agent
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Genus Pseudmonas
- Gammaproteobacteria Order Pseudomonadaceae
- Respiratory type of metabolism (O2 is the final electron acceptor).
- Straight or slightly curved rods
- Motlie by polar flagella
- Catalase positive and usually oxidase positive
- Distributed in soil and water.
- Some pathogenic for humans, animals, and plants.
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Genus Acinetobacter
- Gammaproteobacteria Order Pseudomonadaceae
- group of bacteria found in soil and water.
- Found on the skin of healthy people especially healthcare personnel.
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Genus Vibrio
- Vibrio choleraeGammaproteobacteriaCause of cholera
- Spread in drinking water (Remember John Snow)
- Profuse diarrhea (rice water stools)
- Patients can lose 10 to 15% body weight in < one day.
- Death from kidney failure or low blood volume which are consequences of fluid loss.
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Genus Photobacterium
- Gammaproteobacteria
- Distinguished by bioluminescence
- Electrons bypass the cytochromes of the electron transport chain and instead of ATP, energy is released as light.
- Colonized in the organs of deep sea fish.
FMNH2 + O2 RCHO -luciferase--> FMN + H2O + RCOOH + light.
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Genus Escherichia
- Gammaproteobacteria Order Enterobaceriales
- E. Coli- occurs in the lower partsof the normal flora.
- Some strains cause gastroenteritis, others cause UTI.
- CO2 and H2 produced by glucose fermenation
- usually nonpathogenic.
- Synthesizes vitamin K.
- Hemolytic Uermic Syndrome outbreak in 1993 from undercooked hamburgers. 73,000 cases.
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Genus Shigella
- Gammaproteobacteria Order Enterobaceriales
- Ferment sugars without gas production.
- All stains and species are pathogenic
- Cause of bacillary dysentery or shigellosis.
- The organism is spread by contaminated food, fingers, flies, feces, fomites and water.
- Abrupt onset of diarrhea, often with blood and pus in stools.
- Children are the most susceptible and outbreaks occur in daycare centers.
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Genus Salmonella
- Gammaproteobacteria Order Enterobaceriales
- All strains are pathogenic for humans.
- Causing typhiod fever, gastroenteritis and septicemia.
- Many stains also infect a variety of animals.
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Salmonella typhi
- Cause typhiod fever.
- Only occurs in humans
- Characterized by high fever and speticemia
- Some individuals following infection become chronic carriers and harbor the bacter in the gall bladder
- Typhiod Mary
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Genus Erwinia
- Gammaproteobacteria Order Enterobaceriales
- Mainly associated with plants esp plant pathogens.
- Erwinia amylovora: cause of fireblight.
- Erwinia caratovora: cause of soft rot of fruits and vegetables.
- Erwinia tracheiphila: cause of bacterial wilt of cucurbitaceae.
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Genus Yersinia
- Yersinia pestis: cause of plague or bubonic plague.
- organism is normally maintained within populations of wild rodents and transmitted by fleas.
- The microbe is able to mulitply within the gut of flea.
- Xenopsylla cheopsis: classic vector in urban rat borne epidemics.
- Responsible for the Black Death in 1348.
- Mortality in untreated human cases is 50-60%
- Pneumonic plague occurs when aerosols from a coughing patient are inhaled and has a mortality rate apporaching 100%
- Potential bioterrorism agent.
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Genus Haemophilus
- Gammaproteobacteria Order Pasteurellales
- Parasites of the mucous membranes of humans and animals
- Require preformed growth factors present in blood such as heme &/or NAD.
- Some are pathogenic for humans
- Haemophilus influenzae type B:
- Leading cause of meningitis in infants and children WW
- 1/3 die and 1/3 to 1/2 have serious mental retardation.
- Hib vaccine at 2, 4, and 6 months in the U.S. have reduced incidence of the disease.
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Genus Bdellovibro
- Class VI Deltaproteobacteria Order Bdellovibrionales
- Gram Negative
- Aerobic curved rods with polar flagella
- Predaceous on other gram negative bacteria.
- Attaches to host bacterium and penetrates through both the out membrane and peptidoglycan layer cell well.
- Grows within the periplasmic space.
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Genus Campylobacter
- Class V Epsilonproteobacteria Order Campylobacterales
- Microaerophilic parasites.
- Found in the reproductive organs, intestinal tract and oral cavity of humans and animals.
- Campylobacter jejuni:
- Most common cause of diarrhea in the U.S.
- Est. 2 million infections each year and prevalent in poultry.
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Genus Helicobacter
- Class V Epsilonproteobacteria Order Camplyobacterales
- Microaerophilies parasites
- Found in the upper intestines, and stomachs of humans, dogs, cates, and other mammals.
- Helicobacter pylori:
- Found by Barry Marshall
- Causal agent of peptic ulcer disease and gastritis.
- Also linked to gastric carcinoma.
- Designated as a class I carcinogen.
- Produce enzyme urease
- H2N-C-NH2 + H2O -urease---> 2NH3 + CO2
Double bond O to the first carbon.
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