Chapter 11 Microbial World And You Flashcards
How are the domains and kingdoms now classified?
Via rRNA signatures
Peptidoglycan rRNA signatures gives rise to what Domain?
Pseudomurein rRNA signature gives rise to what Domain?
Domain Bacteria
Domain Archaea
Domain Bacteria is broken down by what distinction
Gram - and Gram +
Gram negative Bacteria is further broken down into what two groups?
Proteobacteria and Nonproteobacteria
How is Gram positive bacteria broken down by?
Low G+C nucleotides and High G+C nucleotides
In Domain Bacteria, how did Proteobacteria get its name?
What are its Characteristics?
From the mythical Greek god Proteus, who could assume MANY SHAPES
Gram Negative
Chemoheterotrophic
They have a photosynthetic ancestor
The relationship is based on nucleotide sequence of ribosomal RNA
How are the subgroups designated by?
Give the names?
Subgroups are designated by Greek letters Alphaproteobacteria Betaproteobacteria Gammaproteobacteria Deltaproteobacteria Epsilonproteobacteria
What are the characteristics of alpha bacteria?
What is the most abundant living organism on earth and where is it found?
Capable of growth at low level nutrients
Some with unusual morphology such as: prosthecae- stalks or buds
Pelagibacter ubique: the most abundant living organism on earth in the ocean
They are very small; only 1354 genes
What are the human pathogens?
Bartonella
Brucellosis
Ehrilichia
Rickettsia
What is Bartonella?
-B. henselae: cat scratch disease
What is Brucella?
What does it cause and its key features?
causes Brucellosis or Malta Fever
Fluctuating fever that spikes every afternoon that is why it is called Undulant Fever
Survives phagocytosis
Ingestion of contaminated milk
What is Ehrilichia? What are its characteristics and how is it transmitted?
Transmitted by ticks
Causes the disease Ehrilichiosis (fever, chills, nausea)
It’s a tick-borne human disease
Obligate Intracellular parasites (WBC)
What is Rickettsia? Characteristics?
Rickettsia: Arthropod-borne. Cause number of diseases know as spotted fever group
What are the three forms of Rickettsia and how are they transmitted?
R. prowazekii - Epidemic Typhus. Transmitted by lice
R. typhi- Ednemic Murine Typhus. Transmitted by the Rat Flea
R. rickettsii - Rocky Mountain spotted fever. Transmitted by tick
For Alphaproteobacteria, they have a prosthecae? What is it and what is it’s purpose?
Have a prosthecae (stalk)
Used for attachment and nutrient absorption
How do alpha reproduce?
No binary fission
Reproduce by bidding (Asexual reproduction)
What Stalked bacteria are found in lakes?
Caulobacter
What budding bacteria are found in lakes? Where else do these grow?
Hyphomicrobium
They also grow in lab water baths
What is Agrobacteriaum?
What is type of research is it important in?
Plant pathogen
They insert a plasma into plant cells, inducing a tumor called a Crown Gall
Important in Biotechnology
Alphaproteobacteria use what for energy? How do they do this?
They are Chemoautotophic and oxidize nitrogen for energy
They fix CO2
How is nitrogen oxidized for Nitrosomonas and Nitrobacter?
Nitrosomonas: NH3 (ammonia).–> NO2- (nitrite)
Nitrobacter: NO2- ( nitrite) —> NO,- (nitrate; a better nitrogen source for plants
What are these nitrogen using bacteria called and what are they important for?
Nitrifying Bacteria
They are important for agriculture
What does Azosprillum and Rhizobium have in common?
Both are nitrogen fixing bacteria
What are the characteristics of Azospirillum? Are they aerobic or anaerobic?
Anaerobes
Lives in close association with the roots of plants (beans legumes)
Nitrogen fixation
What are the characteristics of Rhizobium? Where do they do nitrogen fixation?
Fix nitrogen in the roots of plants (symbiosis)
They induce nodules so important in agriculture by infects the roots of plants beans legumes clovers
What is Acetobacter and Gluconobacter? What is their significance?
What does this produce in industry?
What can this destroy?
Produce acetic acid form ethanol, so important to industry
They are aerobic
Ethanol to Acetic acid (vinegar)
This spoils wine
What are the general characteristics of Betaproteobacteria?
Use Hydrogen gas, ammonia and methane
Some are pathogens
It overlaps with alpha
What is Thiobacillus (Acidithiobacillus)?
What do they oxidize (from what to what)?
Sulfur-oxidizing bacteria: Chemoautotrophic
The obtain energy by oxidizing:
H2S or S (elemental sulfur). To SO42- (sulfate)
What is Spirillum?
What type of energy source and carbon sources does Spirillum use?
Where are they found
Chemoheterotrophic, helical
In fresh water
They are Gram negative
How are Spirillum and Spirochetes different?
Spirillum are motile by a polar flagella
What is Sphaerotilus natans?
Energy, and carbon source type?
Where are they found
Chemoheterotrophic; that form sheaths
Found in fresh water and sewage
Gram negative
What does Sphaerotilus natans have for protection?
What is one if the problems that this contributes to ?
Sheath is for protection and nutrient accumulation
Contributes to bilking; a problem in sewage treatment
What is Neisseria?
Energy and carbon source?
Where are they commonly found?
Chemoheterotrophic; aerobic cocci
Gram negative
Normal Microbiota of the mucous membrane
What are the pathogenic species of Neisseria?
What do they cause?
N.meningitidis: causes meningitis
N.gonorrhoea: causes gonorrhoea
What is Bordetella?
What does it cause?
Energy and carbon source?
Chemoheterotrophic, gram negative, non motile, rods
B.pertussis: causes whooping cough
What is Burkholderia?
What does it cause and where is it primarily found?
Is it motile and if so how?
All motile with polar flagella or tuft.
Gram -
Nosocomial (hospital) infections or Healthcare-associated infections (HAI)
What is the best know species of Burkholderia and where does it grow?
What is this a problem in specific patients? What does it do to their respiratory tract?
B.cepacia: can grow in disinfectants, can degrade more than 100 different organic molecules ad contaminate hospital equipment and drugs
Problem in cystic fibrosis patients because it metabolizes accumulated respiratory secretions
What HAI’s are the greatest since 2011
Pneumonia
Surgical site infection from any inpatient surgery
Gastrointestinal illness
In 2014 there was a HAI study published, what was the results?
2011- there were ~ 722,000 HAI’s in US acute care hospitals
And additionally, about 75,000 patients with HAI’s dies during their hospitalization.
What is the Betaproteobacteria Zoogloea?
Important in sewage-treatment processes such as the activated sludge system.
They form fluffy, slimy mass which is important in the activated sludge system
What is the largest subgroup of Proteobacteria?
Gammaproteobacteria
What are Pseudomonadales? Pseudomonas?
Are the motile and how?
Gram - aerobic rods or cocci
Rods are motile with polar flagella either single or tuft
Opportunistic pathogens in immunocompromised patients
Describe Pseudomonas aeruginosa?
What does it cause
Produces a soluble blue-pigmentation
In weakened patients it can cause: urinary tract infections, but, wound, septicemia, abscesses and meningitis.
Where can P.aeruginosa grow,a new what type of respiration doe they perform?
where are they found?
Can grow in the fridge
Although aerobic, can also upset nitrate to perform anaerobic respiration meaning use nitrogen and final electron acceptor (loss of nitrogen in fertilizer)
They are found in soil and water
They can decompose pesticides that are added to soil
What is Moraxella lacunata?
What does it cause?
Aerobic coccobacilli
Cause Conjunctivitis: inflammation of the eye membrane
What are Azotobacter and Azomonas?
What is their primary function?
Nitrogen fixing
Free living in the soil and important in agriculture
What is Legionella?
Where is it found and what does it cause?
Found in Streams, warm-water pipes, cooling towers.
Intracellular parasites
Causes L.pneumophila (Leginnaires’ disease)
Outbreak in NY 2015
What is Coxiella burnetii?
What does it cause and how is it transmitted?
What is now done to stop this?
Causes Q fever and transmitted by contaminated milk from cattle ticks that harbor the organism.
That is why milk is pasteurized
It’s and intracellular parasite
May form endospores
What is Gammaproteobacteria Vibrio?
What type of respiration does it do?
Where is it found
Anaerobic Gram negative curved rods that are found in mostly aquatic habitats - coastal water
What are two species that are pathogenic of Vibrio?
What do they cause?
V.cholerae causes cholera
V.parahaemolyticus: causes gastroenteritis from raw undercooked shellfish
What is Enteronacteriaceae? What else are they called
Where are they found?
Facultative anaerobic gram negative rods
Also called enterics or coliform
They inhabit the intestinal tract of humans and animals.
How do Enterobacteriaceae move?
They are Peritrichous flagella
What are the characteristics of Enterobacteriacea?
Have fimbriae which help them adhere to surface or mucous membrane
Have sex pili to exchange genetic material which often included antibiotic resistance
Ferment glucose and other carbs
What are some of the important genera of Enterobacteriaceae?
Enterobacter Erwinia Escherichia Klebsiella Proteus Salmonella Serratia Shigella Yersinia
What is Escherichia coli? What are its characteristics?
Produces bacteriocin: lyses closely related bacteria. It’s a facultative anaerobe that inhabits the human intestinal tract. (Which this form is not a pathogen)
Some produce toxins E.coli O157:H7
What can E.coli cause?
Could cause urinary infections and traveler’s diarrhea (which is a food-borne disease)
What is Samonella and what are its characteristics?
Where is it found?
All are pathogens
Found in the normal Microbiota of intestinal tract of poultry and cattle which are warm blooded animals
What species which is pathogenic is divided into more art 2400 serovars?
Salmonella enterica
What does Serotype mean?
What is a Serovars of S. enterica?
Serovars or serotypes are serological varieties that is often used to mean the same thing
S.typhimurium is a serovars of S.enterica
What it’s the Kauffman-White scheme and what does it depend on?
The Kauffman-White scheme is serotyping and it depends on antigens (Ag) on
K capsule
O cell wall
H flagella
What does S.typhi cause?
Causes typhoid fever (the most sever)
What is Samonellosis?
Less sever that typhoid fever and is caused by salmonella
Less severe gastrointestinal disease
Common food-borne illness
What is Shigella?
What is it caused by?
Only found in humans
Causes bacillary dysentery or shigellosis
It’s second to E.coli causing traveler’s diarrhea
What is Klebsiella? Where is it commonly found?
What is its primary diet?
What does it primarily cause?
Found in soil or water
Capable of fixing nitrogen form the atmosphere
Causes nosocomial infections
K.pneumoniae causes pneumonia
What is Serratia marcescens?
What distinguishes it? Where is it commonly found?
Production of red pigment
Found on catheters, in saline irrigation solutions
Cause urinary and respiratory nosocomial infections
What is Yersinia pestis?
What dose it cause and who carries it?
causes plague: the Balck Death of medieval Europe
Rats carry the bacteria and ground squirrels in the American Southwest carry it
Fleas transmit the organism as (vectors)
Respiratory droplets, bits and contact is also the cause of transmission
What is Bubonic Plague?
Called this due to the swelling of lymph nodes
NOT spread from person to person
What is Septicemic plague?
When bacteria enter the blood and causes septic shock
What is Pneumonic plague?
What does it result in?
How is it spread
Infection of the lungs.
100% mortality
Can spread from person to person through aerosols
What is Erwinia? What does it cause and how does it cause it?
Primarily a plant pathogen
Causes soft-rot diseases
The enzymes hydrolyze pectin in plants that cause the cells to separate.
What is Enterobacter cloacae and E.aerogenes?
What do they cause and where are they found?
Cause urinary tract infection
Found in water, sewage and soil
What is Pasturellales (Pasteurella)?
They are non-motile and best now as human and domestic animal pathogens
Pasteurella is mainly a pathogen of domestic animals
What is Pasteurella multocida?
Causes septicemia in cattle and fowl cholera in chickens
It can be transmitted to man by dogs and cat bites
What does Proteus mirabilis cause?
Cause urinary tract, wound infection, infant diarrhea
They are motile, swarming (spreading)
What is Haemophilus Influenzae?
Where is it found and what does it cause and in who?
Inhabits mucous membrane of the respiratory tract, vagina and intestinal tract
Causes meningitis in children
Is NOT the cause of Influenza
What does Haemophilus require to survive?
Requires blood because they are unable to synthesize important parts of the cytochrome system, therefore they need substances from the heme fraction called the X-factor of blood hemoglobin
What is the V-factor that is a cofactors that is also needed by Haemophilus?
What are the X and V factors used for?
(NAD+, NADP+)
In clinical settings the X and V factors are used to identify isolates of the Haemophilus species
What is H.ducreyi?
Causes sexually transmitted disease called Chancroid
Describe a colony of Proteus mirabilis?
A swarming colony that shows concentric rings of growth
What is Francisella? What type of energy is needed and how does it grow in the lab?
Chemoheterotrophic: grows only in complex media that is enriched with blood
What type if disease is Francisella? Who is affected by it?
It’s it s zoonotic disease: meaning diesels of animals transmissible to humans.
Reservoir is rabbit therefore it is also called Rabbit Fever
What cause Tularemia (septicemia)
Francisella tularensis causes Tularemia
What is the Deltaproteobacteria?
Include some bacteria that are predators on other bacteria. Bacteria in this group are slo important contributors to the sulfur cycle.
What is the Deltaproteobacteria Bdellovibrio?
Predators on other Gram - bacteria it attached tightly and after penetrating the outer layer of the bacteria, it reproduces within the periplasm causing the host cell to lyse.
What is Desulfovibrio?
What is its final electron acceptor and what type of anaerobe is it?
Sulfur-reducing bacteria
S as the final electron acceptor
Obligate anaerobe
Where is Desulfovibrio found and what does it produce?
Found in anaerobic sediment and in the human intestinal tract
Produces H2S rotten egg gas
Because H2S is not used as a nutrient, this type of metabolism is called dissimilatory.
What is Myxococcus or Myxococcales?
How do they move?
Classified among the fruiting and gliding bacteria
Vegetative cells of the Myxobacteria move by gliding and leave behind a slime trail.
Large numbers of Myxococcus aggregate to form?
What is differentiation is cause by what?
What do they resemble?
Resting Cells aggregate to form myxospores.
Under proper conditions, spores will germinate, which is triggered by low nutrients
Resemble Eukaryotic cellular slime molds
What is Epsilonproteobacteria?
How do they mover?
Slender gram-negative rods that are helical or curved
Motile by flagella
They are microaerophilic
What is campylobacter fetus?
What is C. jejuni?
Campylobacter fetus is causes abortion in animals
C. jejuni causes food born intestinal disease
Both are vibrios
What is Helicobacter pylori?
Curved rods with multiple flagella
Causes ulcers and stomach cancer
What is the formula for Oxygenic photosynthesis?
What does it use?
2H20 + CO2 —–> (CH2O) + H2O + O2
Light
Uses Oxygen
What is the formula for Anoxygenic photosynthesis?
what does it use?
2H2S + CO2 ——–> (CH2O) + H2O + 2S0
Light
Uses Sulfur not oxygen
What is Cyanobacteria?
Oxygenic photosynthetic bacteria
Used to be called blue-green algae Aerobic Gliding motility They are capable of fixing nitrogen from the atmosphere Filamentous with sheath
How do they fix nitrogen?
Fix nitrogenby using specialized cells called Heterocyst (anaerobic)
They fix nitrogen gas in to ammonium (NH4+)
What type of Cyanobacteria divide by binary fission?
A unicellular, nonfilamentous and they are held together by a surrounding glycocalyx
What are Anoxygenic Photosynthetic Bacteria?
They live in sediments
They can use H2S instead of H2O
Some may also use organic compounds, such as acids and carbohydrates
What are the 4 types of bacteria that do not use O2 but either use H2S or other organic compounds?
Purple sulfur bacteria
Purple nonsulfur bacteria
Green sulfur bacteria
Green nonsulfur bacteria
What are Chlamydias. Characteristics?
Gram negative
No peptidoglycan in cell wall
They are interacellular parasites like Rikettsia
What is Chlamydia trachomatis?
Gram - Coccus bacteria which is the infective agent.
Transmitted by interpersonal contact or by airborne respiratory routes
What disease does Chlamydia trachomatis cause?
Trachoma (blindness)
Urethritis and STD’s
What is Chlamydophila pneumoniae?
Mild form of pneumonia that is found in young adults
What is Chlamydophila psittaci?
Causative agent of the respiratory disease psittacosis
Psittacosis: a disease of birds that could be transmitted to man
What are Bacteroides?
Where are they found?
Anaerobic and gram negative
Bacteroides are found in the mouth and large intestine
What do bacteroides cause?
Cause peritonitis: inflammation of the bowel
What is Fusobacteria?
Anaerobes, pleomorlphic, spindle shaped
Where are Fusobacterium and what types of diseases are they involved in?
Are found in the mouth and may be involved in dental diseases.
They are slender gram negative bacteria with pointed ends
What are Spirochetes
Have a coiled morphology, resembling a metal spring
Motile by at least 2 axial filaments (or endoflagella) that rotates in the opposite direction like a corkscrew
Found in the oral cavity
What is Treponema pallidum?
Causes syphilis
What is Borrelia?
What does it cause?
Causes relapsing fever and Lyme disease
What is B. burgdorgeri, what does it cause?
Causes Lyme disease
Transmitted by ticks or lice.
Ticks must remain on host for 36-48 hours to transmit the spirochetes
What is Leptospira?
Causes leptospirosis
Spread by water contaminated wth urine of dog, rats, swine
How are Gram positive bacteria classified? What are the two groups?
Classification is based on G+C contents
Those that have high G+C ratio and those that have low G+C ratios
Firmicutes have what G+C ratios
Low G+C ratios
They are gram + bacteria
Firmicutes include what two endospore forming bacteria?
Clostridium and Bacillus
What is Clostridium?
Endospore-producing that are important in medicine and food
Obligate anaerobes
What is C.tetani?
Causes tetanus
What is C.botulinum?
Causes botulism
What is C.perfringens?
Causes gas gangrene and food-borne diarrhea
What is C.difficile?
Normal inhabitant of intestinal tract
Could cause senior diarrhea if antibiotics kill other organism and let overgrowth by toxin-producing strains
What is Epulopiscium?
What does the name mean
Lack nutrient transport systems, use simple diffusion to obtain nutrients
Large cigar-shaped
Live symbiotically in the gut of Red Sea Surgeon Fish
Name means guest at the banquet
How does the Epulopiscium reproduce?
Describe internal structures?
Does not reproduce by binary fission
Daughter cells are formed within the cell and are released through a slit opening
Has flagella and didn’t have a membrane enclosed nucleus
What is the morphology of Bacillaes?
Includes several genera of Gram + rods and cocci
What is Bacillus?
Endospore-productions rods
Found in soil and few are harmful to humans
Some produce antibiotics
What is B.anthracis?
What is the disease?
Non-motile, facultative anaerobe that forms chains.
Causes anthrax
Anthrax is the disease of cattle, sheep and horses that can be transmitted to man
Agent of biological warfare
What is B.thuringiensis?
Best know microbial insect pathogen that produces Intracellular crystals when it sporulates.
What is B.cereus
Cause of food poisoning primarily in starchy foods such as rice
What is Staphylococcus?
Grape-like cluster of cocci
Facultative anaerobes
What is the most important species of Staphylococcus?
What are its characteristics?
S.aurues: yellow pigmented colonies- also facultative anaerobes
Found in nasal secretions
Where does S.aurues grow?
Grows in food with high osmotic pressure, like cured foods: ham, and cured meats or in low moisture foods that tend to inhibit growth.
What does S.aurues cause?
What are the symptoms
Produces toxins can cause toxic shock syndrome
High fever, vomiting and sometimes death
Infects surgical wounds in hospitals
Also produces Enterotoxin that causes vomiting and nausea which is the common cause of food poisoning
What is Lactobacillus?
Where is it found?
Used for lactic acid production and fermentation of buttermilk, yogurt, and sauerkraut
Normal Microbiota of the Vagina, intestinal tract, mouth (oral cavity)
Most lack a cytochrome system and are unable to use oxygen as a final electron acceptor
What is Streptococcus?
Spherical gram + bacteria that appear in chains
They are probably more responsible for causing illness and a greater variety of diseases than any other group of bacteria.
They make products that protect them from phagocytosis
They spread infection by digesting the host’s tissues
How are Streptococcus classified?
Classified based on action on blood agar.
Alpha-hemolytic: produces alpha hemolysis that reduces: hemoglobin Red—>methemoglobin (greening)
Beta-hemolytic: produces hemolysis that create a clear zone on blood agar
Gamma-hemolytic: non-hemolytic
What is Streptococcus pyrogens, and what does it cause?
Beta hemolytic
Causes scarlet fever
Pharyngitis
Pneumonia
Rheumatic fever
What is Streptococcus mutans?
Causes dental caries (cavities)
What is Enteococcus and what does it cause?
They adapt to area of the body that are rich in nutrients but low in oxygen like the gastrointestinal track, vagina, oral cavity and stool.
Responsible for nosocomial infections that have developed a high antibiotic resistance
What is E.faecalis and E.faecium cause?
Responsible for wound and urinary tract infections
They are resistant to most antibiotics
What is Listeria? What does it cause?
L.monocytogenes?
Where do they grow?
Who are they the most problematic to?
Can contaminate food
Contaminate dairy products
They survive phagocytosis
Grows at refrigerator temps
Infection in pregnant women poses serious damage to the fetus
What are Mycoplasma? What are their characteristics?
They are wall-less; pleomorphic many shapes
Very small .1 - 0.24 micrometer
No gram-stain
Produces filaments like fungus (myco)
What does Mycoplasma pneumoniae cause?
Causes walking pneumonia (mild)
What does Mycoplasma look like?
What environment do they need to grow?
Look like a fried egg appearance
Need sterol in media to grow
Grow in cell culture
Which phylum has High G+C Gram positive bacteria in it?
Actinobacteria
What is mycobacterium?
What is M.tuberculosis?
Aerobic, non-endospore-forming rods
Have a waxy cell wall made of mycolic acid
M.tuberculosis causes the disease tuberculosis
What it Streptomyces?
Best known of the Actinomycetes
Found in soil
Strict anaerobe
Most produce antibiotics
Produce a musty odor
How do Streptomyces reproduce?
Reproduces by forming asexual spores called Conidiospores
The spores travel and land on substrate and germinate
What is Actinomyces and where are they found?
Facultative anaerobes that are found in the mouth and throat of humans and animals
What is Actinomyces israelii? What does it cause?
Causes actinomycosis which is a tissue destroying disease
What is Corynebacterium? Describe it characteristics?
What is C.diptheriae?
Coryne= clubs shaped
C.diptheriae is the causative agent of diphtheria which causes bacterial infection of the upper Respiratory system
What is Propionibacterium?
What is P.acnes?
Produce propionic acid; important in fermentation of Swiss cheese
P.acnes cause acne that is found on human skin
What is Gardnerella?
What is G.vaginalis?
Gram variable therefore hard to classify
G.vaginalis causes vaginitis
Frothy vaginal secretions with a characteristic fishy odor (whiff test) when tested with potassium hydroxide
What is the characteristics of Domain Archaea?
What separates them from the two other Domains?
Lack cell wall. If they do, there is no peptidoglycan in cell wall
rRNA sequences are different from the other two Domains
They are rods, cocci, helixes and unusual morphology
How do Archaea reproduce and what are their nutritional characteristics?
Some divide by binary fission, some by fragmentation, some by budding
They are nutritionally very diverse and live in extreme environments, such as chemoautotrophs, photoautotrophs and chemoheterotrophs
