EXAM II MICROBIO Flashcards
preserving bacterial cultures
deep freezing: helps draw cultures (-50C to -95C)
lyophilization: removes water, becomes powder form (-54C to 72C)
Winograsky column
distributes microbes, preserved for years
“zones of development”
gene sequences of ___ suggest there are more than 80 phyla
16 SrRNA
4 phyla of bacteria
proteobacteria
actinobacteria
firmicutes
bacteroidetes
proteobacteria
-gram negative stain
-diversity of form (various shapes)
-share common form of cell envelope
5 classes of proteobacteria
alphaproteobacteria
betaproteobacteria
gammaproteobacteria
deltaproteobacteria
epsilonproteobacteria
alphaproteobacteria
nitrogen fixing –> agricultural importance
obligate or facultative intracellular
oligotrophs: grow at low level of nutrients
What is an illness of alphaproteobacteria
Rickettsia
-R. rickettsi: rocky mountain spotted fever (face rash)
infects ticks, human becomes infected after tick bite
Betaproteobacteria
wide range of environments
Neisseria (gram -, coffee bean cocci) : fastidious, difficult to culture
-require moisture and CO2, grow on chocolate agar
*Gonnorhea
*Bacterial meningitis
Gammaproteobacteria
largest subgroup of proteobacteria
PSEUDONOMAS:
gram negative bacillus
pyanocin: soluble green culture
aerobic
hospital acquired infections, cystic fibrosis
grow in low temp
grow on soaps, antibiotics
-anti drug resistant
pseudonomas aeruginosa
aerobic, gram -, highly motile
grows in soil as decomposer
infect surgical wounds or form biofilms in CF
resistant to antibiotics and form biofilms
Legionella pneumophila
related to pseudonomads
grow in warm waters
grow inside ameba and human macrophages
transmitted to humans via inhalation of aerosolized ameba with Legionella inside
Deltaproteobacteria
sulfate or sulfur reducing
gram negative
Bdellovibrio: obligate aerobe, parasitic (feed on other bacteria)
Desulfovibrio: reduce sulfur, remove toxic wastes
Myxobacteria: colonies, live in soil by gliding
Epsilonbacteria
slender gram negative rods, helical or curved
Campylobacter: spiral rod, microaerophilic, infect chicken, transmit to humans via uncooked chicken
Helicobacter: spiral rod, damage inner lining of stomach
motile flagella
Gram positive is differentiated by
low or high G+C nucleotides in their DNA
Firmicutes
form endospores ex. Clostridum, Bacillus to resist environment changes
-lactic acid
-LOW G+C
Bacteria with gram positive cell walls
*firmicutes
*actinobacteria
Bacillus
endospores
B. thuringiensis: insecticide
B. anthacis: anthrax
B. cerus: food poisoning
Clostridium (forms neurotoxins)
obligate anaerobes
form endospores (club-shaped)
C tetani: tetanus, spastic paralysis
C botulinum: botulism, flaccid paralysis
C perfringens: has gangrene
C dificile: diarrhea, microbiota eradicated by antibiotics
Mycoplasma (firmicutes)
lacks cell wall
Actinobacteria
non- endospore forming
HIGH G+C
peptidoglycans in cell wall
Listeria spp (firmicute)
intracellular pathogen causing diseases Gi tract and nervous system
-Listeria monocytogenes: delivery, miscarriage, stillbirth
gram positive cocci (firmicute)
enterococcus
streptococcus (chains)
staphylococcus
streptococcus
chains, aerotolerant
grow in O2, ferment sugar (lower pH to dimeralize)
lack ETC
oral cavity, skin, intestines
site: blood clot –> spread to other tissues
groups of streptococci
pyogene (strep throat)
viridans (dental carries)
blood agar hemolysis
destroys RBCs, complete RBC hemolysis - Beta hemolysis
- S pyogenes: strep throat
-S. agalactiae: neonatal sepsis, meningtis
alpha hemolysis of streptococci
incomplete hemolysis, greenish, hydrogen peroxide produced
presence of oxygen
S. pneumonae
S. mutans: causes dental caries
streptococcus structure
chains
staphyloccus
facultative anaerobe
grapelike cocci clusters
tolerate drying and high salt
nasal secretions
S. epidermis: skin scalded syndrome, bone infection
S. aureus: wound infection, antibiotic resistance, produces enterotoxin
enterococcus (nonspore firmicute)
fecal origin
found in intestinal tract, hands, bedding, hospitals
antibiotic resistance
E faecalis and faecium infect surgical wounds and urinary tract
vancomycin
Staph Aureus is resistant to
methicillium
MRSA (methillium resistant StaphA)
mycoplasma
pleomorphic
self- replicating
lack cell wall
M. pneumonae causes mild pneumonia
actinobacteria
-high G+C
-gram positive bacteria
-pleomorphic, some branching
actinomycetes
form mycelia with branching filaments
streptomyces
Streptomyces coelicolor: produces many antibiotics
Frankia: older trees, nitrogen-fixing
nocardia: acid fast
N. asteroides cause pulmonary infections
actinobacteria
mycolic acid, acid fast
dont form mycelia
Gardenella vaginalis
Corynebacterium diphterae: metachromatic granules white greyish membrane is formed blocking the air to reach lungs
DTap
Propionibacterium freduenrichii makes swiss cheese (ferm.)
cutibacterium: found in skin, acne
mycobacterium (actinobacteria)
high G+C
common in soils
acid fast bacilli (mycolic acids)
mycrobacterium tuberculosis
-tubercle: lumps/knots -> Grohns complex -> bacteria -> latent infection
M. leprae: PNS loss of sensitive disfigurement nodules
Deinococcota
-actinobacteria
-resist radiation
-unique DNA
-red or pink
Thermus aquaticus
hot spring in Yellowstone
source of Taq polymerase- thermotolerant enzyme used in Polymerase chain rx
gram negative nonproteobacteria
chlymydia
spirochetes
CFB
plantomycetes
chlamydias
lack cell wall but not mycoplasma
obligate parasites/ pathogens
life cycle of chlymadia
- elementary body attach to host (infective, condensed DNA)
- endocytosis
- EB differentiates to reticulate body (cytoplasm, uncondensed- threadlike)
4.RB replicates
5.RB develop into EB - cell lyses - release EB
elementary body of chlymadia
small, dense and reisstant to drying and means of dispersal
specialized for infectious transmission
reticulate body of chlymadia
vegetative form, divide by binary fission
noninfectious
convert to elementary body when host cell disintegrates
types of chlymadia
trachomatis: blindness in humans, STD
psittaci: respiratory psittacosis (birds and humans)
pneumonae: pneumonia
spirochetes
twisted
spiral shaped
darkfield microscope
trepoma pallidum: syphillus
endoflagella in periplasm, outer sheath
genus Borrelia
B burgdorferi causes lyme disase
B recurrents cause Louse born relapse fever
CFB group
cytophaga
fuscobacterium
bacteroides
*nonproteobacteria gram negative
cytophaga
motile aquatic bacteria that glide (slimy substance is released)
degrade cellulose and chitin in soil
fuscobacteria
anaerobic
in mouth –> dental abscesses
bacteroides
obligate anaerobe
human colon: fermnent ingestible sugars and breakdown toxins
Bacteroides thetaiotamicron: in lumen of large intestine –degrades complex polysaccs
phototropic bacteria
both proteo and nonproteo
use sunlight as energy
oxygenic photosynthesis: cyanobacteria
anoxygenic photosynthesis
classified into sulfur and nonsulfur bacteria - hydrogen sulfide
purple and green sulfur bacteria use
reduced sulfur ie. Hydrogen sulfide and produce sulfur rather than oxygen
what compounds carry out anoxygenic photosynthesis
green sulfur bacteria: Chlorobi
green nonsulfur bacteria: Chloroflexi
purple sulfur and nonsulfur are proteo
cyanobacteriaa
oxygenic photoautotrophs
fix nitrogen
changed anoxic atmosphere -> oxygen
heterocysts - specialized cells
cyanobacteria bloomds
swimmers
peptide
toxins
*edible spirulina salad
purple sulfur bacteria
purple bc carotenoid pigments
capture light
transfer e- to bacteriochlorophyll
plantomycetes
gram negative, budding bacteria
cell wall resemble archae
organelle resemble eukarya
gamma obsuriglobus: membrane around DNA, resemble eukaryotic nucleus
Gemmata obscuriglobus
double membrane surrounding nucleoid resmbles a eukaryotic nucleus
enterobacteriacae (gammaproteobacteria)
enterics: intestinal tract
facultative anaerobes: motile, commensals + pathogens
flagella cell surface
salmonella
salmonella enterica: 3500 seratypes - serover –> salmonella externica - typhmminum - person to person via water and feces
salmonella enterica: food illness
salmonella typhi: typhoid fever (person to person)
Escherichia
e coli
-food contamination
-UTI
gammaproteobacteria
shigella
klebsiella
serratia
proteus
yestinia
erwina
shigella (gamma)
e. coli, shiga toxin
klebsiella
solid, nitogen fixing
k. pneuomnaie: causes pneumonia
serratia
produces red pigment
nosocominal infections- hospital acquired via catheters, saline irrigation tubes
proteus
swarming motility, colonies form concentric rings
-uti, kidney stones, pH alkaline
proteus mirabilis: concentric rings, have flagella in edges, center = loose flagella
yestinia
Y pestis causes plague
fleas
erwinia
plant pathogens
pectinase- hydrolyzes pectin
archae
pseudopeptidoglycan
five major phyla:
crenarcheota
euryaarcheota
korarcheota
nanoarcheota
thaumarcheota
crearcheota
aquatic organisms
aerobic: heterotroph
anaerobe: store sulfur
sulfolobus:
-thermophile, acidophile
-oxidizes sulfur; used for thermostable and acid- resistant protiens
thermoproteus:
-lipid monolayer instead if bilayer
-strictly anaerobic
-deepest branching genus of archae
-plants earliest forms of life
-reduce sulfur or hydrogen and use CO2 or CO as carbon source`
euryachaeota
methane producing archae
Halobacteria
-high conc of sodium chloride
-photosynthesis using bacteriorhodopsin
two main types of microbiota
permenant
transient: temporary -> pathogens
human microbiota: mutualistic relationship
mutuatlism (symbiotic)
both benefit
ex. e coli
amensalism
one is harmed, other is unaffected
commensalism
one is benefitted, other is unaffected
ex. S. epidermis (dead cells benefit) on skin
parasitism
one benefits, other is harmed
ex. influenza virus
neutralism
both are unaffected
acidic environment
inhibits growth of other pathogens
locatioons of commensal microorganisms
skin: Staph epidermis
oral cavity: no teeth - aerotolerent bacteria - streptolococcus between teeth - teeth gums - anaerobic - Streplolococci fuscobacterium
upper respiratory tract
intestines
urogenital tract: lactobacillus - vagina - glycogen and candida inhibit yeast grown in vagina
GI tract health is influenced by
host
genetics
diet lifestyle
adults (vaginal health)
lactobacillus -> lactic acid -> yeast infections
before puberty (vaginal health)
pH is neutral
Strapholoccus, Streptolococcus
vaginal birth vs cesarian birth
vaginal: lactobacillus and bacteroides
ceserean: staph aureus; nosocomial pathogens
eukaryotes
fungi:
-microscopic
-hyphae filament
-yeast single cell
protozoa:
-first animal
-amoeba
-paramecia -> motile
algae:
-plants
-algae: chloroplast - motile
fungi and microsporidians
lack motility
tough cell walls
heterotrophs
lignin
cilates
cilia
some are parasites
apicomplexans
apical complex allows attachment and penetration of host cell
helminths
multocellular worms
arthopods
multicellular insects
fungi
many are beneficial: recycle vital elements
decompose dead plants, recycle elements – Saprophytic
mycorrhizae form symbiotic relationships w plants and help absorb water
penecillin: antibiotic production
food: beer, cheese
mycology
study of fungi
chemoheterotrophs - decompose organic matter
aerobe or facultative anaerobe
aerobes
use sugar to produce carbon dioxide and water
facultative anaerobes
ferment to produce ethanol and CO2
fungi vegetative structures
-fungal thalamus (body) has hyphae filaments
-septate hyphae: contain cross walls (divided but cytoplasm connected)
-coenocytic hyphase: no septa (continuous)
hyphae
mass of hyphae is mycelium
hyphae grow by elongating at tips
vegetative vs aerial hyphae
vegetative: obtain nutrients
aerial: reproduction
pseudohyphae
doesnt divide but invades deeper tissues
yeasts (fungi vegetative)
unicellular
budding: 24 daughter cells; divides unevenly - sacchomyces
fission: divide evenly - schizosacchromyces
dimorphic fungi
yeast at 37C
mold at 25C
how do fungi reproduce
sexually and asexually via spore formation that detach from parent and germinate into new mold
life cycle of asexual spores
mitosis and cell division
formed by hyphae of one organism
-conidospore: not enclosed in sac
-anthroconidia: fragments septate hyphae
-blastoconidia: buds of parent cell
-chlamydoconidum: spore within hyphal segment
-sporagniospore: enclosed in sac
life cycle of sexual spores
fusion of nuclei from 2 opposite mating strains
diploid zygote
meoisis: diploid nucleus produces haploid nuclei (sexual spores)
fungi environmental and nutritional adaptations
grow best at pH 5
oxic/ anoxic:
-molds: aerobic
-yeasts: facultative anaerobe
grow in high sugar and salt, resistane to osmotic pressure
grow in low moisture
require less nitrogen than bacteria
metabolize complex carbs - lignin
medically important fungi
mucoromycota
microsporidia
asomycota
basidomycota
mucoromycota
conjugation
coenocytic hyphae
produced asexually: sporangiospore
sexually: zygospere - form when nuclei of two similar cells fuse
ex. Rhizopus stolonifer - common black bread mold
life cycle of Rhizopus (zygomycete)
-usually asexually
asexual reproduction
aerial hypha -> sporagium->spore -> hyphae
sexual:
plasmogamy: penetrates cytoplasm
zygospore forms -> meiosis -> sporagium -> spore -> hyphae
microsporidia
no sexual reproduction
no mitochondria
obligate intracellular parasites
diseases –
chronic diarhea
keratoconjunctivitis
ascomycota
sac fungi, septate hyphae
asexual rep by budding
some are anamorphic: lose ability to sexually reproduce
-asexual production: condiospore
-sexual production: ascospore
nuclei fuse in saclike ascus
sacchromyces, candida, aspergillus
basidomycota
mushroom
club fungi
septate hyphae
asexually produced: condiospore
sexually produced: basidospore
-formed on base pedestal called basidium
genera: amanita, agarius
amanita: highly poisonous
human fungal pathogen: crypotococcus
mycosis
fungal infection
chronic, slow growing
5 types of mycoses
systemic: deep within body
-soil -> inhaled -> lungs -> different tissues of organs
subcutaneous: beneath skin
superficial: localized (hair shaft)
oppurtunistic: fungi harmless in normal habitat but pathogenic in compromised host
cutaneous mycroses
affects hair, skin, nails
aka “dermatomycoses”
trichophyton: infect hair, skin, nails
microsporum: only hair or skin
epidermophyton: skin and nails only
subcutaneous mycroses
penetrate statum corneum
caused by soil fungi
wound -> spore
sporotrichosis enters wound, forms ulcer
histoplasmosis
dimorphic fungus
grows intracellularly in macrophages
negative tuberchlosis skin test
acquired from airbone condia in areas with bird or bat droppings - lower body temp - shed in feces
cocidiomycosis
valley fever
caused by coccidiodes immitis - dimorphic fungus
form a sphreule filled with endospores in tissues
fever, coughing, weight loss
resemble tuberchlosis
blastomyosis
caused by blastomyces dermatidis
-dimorphic fungus
-grows in soil
symptoms resemble bacterial pneumonia - cutaneous abcess, extemsive tissue damage
pneuomocystis pneumonia (PCP)
yeast like fungus
asymptomatic in immunocompetent causes pneumonia in immunocompromised
*indicates AIDS
-found in alveoli lining
-forms cysts
-cysts rupture, releasing 8 trophozoites
candidiasis
C. albicans
-forms pseudohyphae making it -resistant to phagocytosis (invade deeper tissues)
-mucous membranes and genitoruinary tract
trush = infection of oral cavity
results when antibiotics supress competing bacteria or changes in mucosal pH
glycogen increases
increases pathogens
Cryptococcosis
soil fungi
pigeon and chicken dropings
transmitted through respiratory route
immunocompromised: meningitis
*phagocytosis
aspergillas fumigatas
causes aspergillosis
airbone conidia - decaying vegetation
rhizopur and mucor
mold spores
predisposing factors - cancer, diabetes, immunocompromised state
mycotoxins
toxins produced by fungi
-blood diseases
-nervous system disorders
-kidney damage
-liver damage
-cancer
ergot poisoning
myxotoxins produced by Claviceps purpurea
-occurs in rye grains
-restricts blood flow (gangrene) and causes hallucinations
aflatoxin poisoning
mycotoxins produced by aspergillus flavus
-causes liver cirrhosis and liver cancer
aspergillus niger (fungi)
produces citric acid
aspergillus terreaus
statins inhibit cholestrol synthesis
saccharomyces cerevisae
bread, wine, hepatitis B vaccine
trichoderma
cellulase
degrades outer covering of fruit
taxomyces
taxol: anti-cancer drug
coniothyrium minitans
kills fungi on crops
biological pesticide
lichens
controlled parasitism
mutualism of green algae and fungus
3 categories:
crustose - encrusted on substratum
foliose- leaflike
fructicose - fingerlike
thalus (body) of lichens is made of
medulla - hyphae grown around algal cells
rhizines- hyphae below body
cortex- protective coating over algal layer
lichens first colonize on
rock or soil
-indicates air pollution
-superoxide
-differentiated based on morphology
alga produce and secrete
carbohydrates
fungus provides holdfast
importance of lichens
dyes - litmus, eryhtrolcetin - pH
antimicrobial - usnic acid
litmus
food for herbivores
algae
aquatic: nutrient reproduction
or phototrophic
unicellular or filamentous photoautotrophs
lack roots stems and leaves
mostly aquatic
characteristics of algae
location depend on nutrient availability, light wavelengths and surfaces to attach
pnemocyst: floating gas filled bladder
-have sexual and asexual reproduction
mostly photosynthetic, chrolorophyll
oomycotes: chemoheterotrophic
-fungus like algae, plant parasites, potatoes, soybeans
brown algae (kelp)
cellulose and alganic acid cellwalls
produce algin - thickener used in foods
red algae
multicellular
live in greater depths
harvested for agar and carrageenan
green algae
cellulose cell walls
unicellular or multicellular
store starch
chlorophyll a and b