Microbiology 1 Flashcards
MICRO stand for?
M: microscopic I: independent C: comparatively less complex R: rapid rate of reproduction/multiplication O: omnipresent (present everywhere)
Vitamin K:
A) function
B) which microbe makes it?
C) facts? (what cause Vit K deficiency?)
Vitamin K is essential for blood coagulation
Made by large intestine BACTERIA: E Coli
facts:
newborn are given vit K shots (they dont have bacteria when they are born, unlike adults)
Vitamin K deficiency:
1) major large intestine surgery
2) long term antibiotics
3) defect in bile synthesis (vit K is fat soluble and need bile to be absorbed)
Resident microflora vs Transient microflora
Resident: permanent, through life (causes no harm in most case)
Transient: remains hours/days/months
fail to persist due to competition from others (nutrient, space), elimination from body defense cell, physical/chemical change (sweat. etc)
Division/Organization of Microbial world
living and non living:
nonliving: virus, viroids, and prions.
Living: (3 domain) bacteria, archea, and eucarya.
bacteria and archea are prokaryote (unicellular) (before nucleus, have nucleoid area instead)
Eucarya (all eukaryote) is further divided into:
a) algae (uni or multicelullar),
b) protozoa (unicellular)
(both called protist),
c) fungi (uni or multi cellular)
d) helminths (multicellular parasite)
Prokaryotic vs Eukaryotic cell
1) Prokaryote: DNA not enclose in membrane (no nucleus), have nucleoid area
Eukaryote: Nucleus present to confine DNA
2) prokaryotic have one circular chromosome, eukaryotic have multiple chromosome
3) prokaryotic have NO membranous organelle (only non membranous organelle: cytoskeleton and ribosome). Eukaryote have both membranous and non membranous organelle
4) Prokaryotic have cell wall made of peptidoglycan (primitive). Eukaryote, IF have cell wall, is simply, no peptidoglycan.
5) Prokaryote only non histone protein present, Eukaryote have both histone and non histone proteins present (associated w dna)
(Histone and nonhistone protein are two types of proteins present in the chromatin structure of DNA. They perform various functions related to DNA. )
6) Prokaryote divide via binary fission, Eukaryote divide via mitosis.
Membraous vs Non membranous Organelle
Membranous organelle:
mitochondria, golgia apparatus, endoplasmic reticulum, lysosome, nucleus, transport vesicle, vacuoles,
Nonmembraous organnlle: ribosome, cytoskeleton, centrioles, protesome.
(note: prokaryote only have non membranous organelle: ribosome and cytoskeleton)
eukaryote have everything here.
Virus:
DNA VS RNA VIRUS
EITHER DNA OR RNA (NEVER BOTH gnome, unlike us or bacterial cell which can have both)
DNA virus:
Human papillion virus (HPV), herpes virus family, small pox, HEP B,
RNA Virus:
SARS, corona virus 2, 1, polio virus, influenza virus, common cold, rabies, measle, HIV, HEP C, HEP A virus.
VIRUS is UNIQUE b/c it can contain RNA as gnome in the biological world, this is rare. (most contain dna)
How is virus transmitted?
They lack flagella, cilia, etc so NO mobility unlike bacteria.
They are PASSIVELY transmitted via air, body fluids, blood, etc.
minimal: insect bite, needles, mucosal surface
maximal: aerosole, winter, etc.
How are virus particles formed (produced)?
NO binary fission, NO mitosis. (unlike us or bacteria)
Virus particle formed by de novo assembly (fresh/ newly synthesized components) within host cell
How are virus grouped?
Into “families”; NO binomial nomenclature.
ex: rabies family, corona virus family, herpes family, etc.
PRIONS
proteinaceous, infectious, virion
protein molecule w/ infectious quality similar to viral gnome BUT NO GENETIC MATERIAL
prion protein conversion
normal; cellular form: PrPc
common in our neuron membrane)
protease sensitive, alpha helix
> > > > > > templating»>
misfold form: PrPsc (scarpie form)
protease resistant, beta helix sheet.
abnormal prions protein acts like negative influence teenager on normal prions, converting them slowly.
Dual behavior of prions, unknown amongst microbial pathogens
they are inheritable and transmissible.
Prions characteristic/structure
protein sequence identical to normal brain protein
slow incubation period (as long as 20 years) thus hard to detect
highly resistant to UV, ionizing radiation, high temp (remain active event at 90C),
not destroyed by enzymes that digest nucleic acid (DNase, RNase) (thus it is nuclease resistant)
they are inheritable and transmissible.
Why is prions infection not common, given that we have the specific protein as a membrane protein?
what is the exception?
Adjacent protein and polysaccharide in membrane lipid raft force (cholesterol enrich areas) the PrPc into correct shape (hard for it to be folded into misfolded shape) (remain in alpha helix form)
EXCEPTION:
if PrPc has methionine amino acid at 129 position, then higher risk of prion disease.
Prion transmission and spread in humans
1) inherited
2) Spiradic
3) Infectious
Prion disease
1) KULU (from eating brain, cannibalism)
eat brain, get infected, slow incubation period + pass on prions (transmit + inherited= deadly combination) cycle repeat and hard to detect or catch.
2) CJD (Creutzfeldt-Jakob disease)
caused by prions not killed by sterilizing equipment. prions build up in cells, brain slowly shrinks and tissue has holes in it.
consequence: dementia, lose ability to think, fata within one year.
(1 in a million @ 60 years)
3) vCJD (variant form)
caused from eatting infected food such as contaminated beef.
4) fatal insomnia
Why do brain get sponge in prion disease?
When prion protein is altered, lysosome see it as foreign and try to get rid of it.
uses hydrolytic enzyme (but because prions is protease resistent, it doesn’t die). the brain however get a hole/sponge from collaterol damage)
Prions Disease in Animal
1) Scrapie (common in sheep goat)
scratch to death
2) Wasting disease
elk
3) mad cow disease
AKA bovine spongiform encephalopathy
(cure, solution is to incinerate animal and entire herd)
possible tx for prion disease
antimalarial drug
antipsychotic drugs
antihistamine
***mitigate prion disease in animal
Fungi
Eukaryote.
uni/multicellular
natural decomposer (recycle more element back to environment via soil fungi)
chitin cell wall (target of antifungal)
absorb nutrients like bacteria
ex: yeast
Algae
Eukaryote (and protist along with protzoa)
uni/multicellular
free living, aquatic
cellulose cell wall
synthesize sugar(photosynethesis), dont extract organic material/
green, contain chloroplasts
ex: euglena
Protozoa
eukaryote (protist along with algae)
unicellular ONLY
free living parasite (can cause disease to us)
no rigid cell wall
ingest particle of organic matte (carbon and energy sources)
ex: paramecium
disease ex:
trichomoniasis: Affect both M and F.
a very common sexually transmitted disease (STD). It is caused by infection with a protozoan parasite called Trichomonas vaginalis.
Helminthes
Eukaryote.
parasitic worms
3 types/classes
1) round worm
2) tape worm
3) flukes
complex life, multiple host, cause disease in both animal and humans. help with attachment.
“hooks” on the worms are called scolex.
they have both testes uterus and ovary (asexual?)
Bacteria
characteristic and fx
prokaryote. unicellular.
rigid cell wall: peptidoglycan (normally present)
few structure, versatile metabolic process (flexible with carbon and energy usage, can vary)
well adapted for survival
obtain nutrients via absorption (except those that use photosynthesis)
What does bacteria rapid growth rate lead to?
- accelerated rate of evolution like antibiotics resistance
- genetic changes that are rapidly incorported into the bacterial population and impact the environment (ex, alaska oil spill, oil eating bacteria)
- broader distribution; are found everywhere.
Archea
characteristic, fx
Prokaryotic. “ancient bacteria”
rigid cell wall, if contain, pseudopeptiglycan
absorb nutrients like bacteria
NON pathogenic (no disease), harmless.
inhabit extreme environment:
A: halophiles
halobacterium spc: found in extreme salty environment
B: Theromophles:
thermophiles spc: thrive @ extreme high temperature (nuclear power plant, valcano, etc)
C: methanobacterium spc
found in intestine of cows
end product of these are methane gas instead of CO2
bacteria vs virus
bacteria is independent. virus is dependent on host
bacteria have cytoplasm, ribosome, and membrane.
virus DONT.
bacteria genetic material is DNA AND RNA (both).
virus is only either dna or rna (never both)
bacteria (prokaryote) have no nucleus (no nucleocapsid) and have nucleoid area. virus have nucelocapsid present to protect.
bacteria have cell wall
virus do not have cell wall
bacteria shape: 3 basic shape
Cocci: sphere
bacilli: rod shaped (pointed, spindle shape, or filamentous)
spirals: rigid (spirillum) or flexible (spirochete)
Medically important spirochete (spiral bacteria that is flexible)
Syphilis (Treponema pallidum) (STD)
Borrelia burgdorferi (Lyme Disease)
Leptospirosis (Leptospira interrogans) rarely fatal
other bacteria shape (other than the common 3)
vibrios: slightly curve rods
(vibrocholarae, vibriovulnificus (can be fatal)
coccobacillus: partly cocci partly bacilla (sphere but rod shape)
ex: bordetella pertassis: whooping cough pathogen
star/square shape:
mainly aquatic environment. function is to increase surface ara thus increase absorption.
PLEOMORPHIC:
variation in shape and size
ex: corynebacterium diphtheriae (rod shape may swell on either end depending on phospherus absorption/accumulation)
mycoplasma pnemonia (walking penumonia)
PLEOMORPHIC:
PLEOMORPHIC:
variation in shape and size
ex: corynebacterium diphtheriae (rod shape may swell on either end depending on phospherus absorption/accumulation)
mycoplasma pnemonia (walking penumonia)
2 factor that affects outcome of binary fission (bacterial cell arrangement)
1/ plane of division
2 daughter cell remain attached or separate
COCCI cell
different arrangements
1) diploocci:
two cell attached
ex: neisseria gonorrhea
2) streptococci:
long chain of cocci (sphere)
ex: streptococcus pyogenes (strep throat infection)
streptococcus penumonia
3) tetrad:
2planes perpendicular to each other (4 cocci attached)
ex: miccococcus luteus
4) sarcinae:
3 planes, cuboidal packet, small cluster of 6ish cocci
5) staphylococci
random plane of division
cell remain clustered (bundle of grape)
ex: staphylococcus epidermidis
staphylococcus aureus
Bacili cell
different arrangemets
Less variation in arrangement than cocci because they only divide along shorter axis.
a) normal rod shape
b) streptobacilli: long chain
c) diplobacilli: 2 rods
d) v shape:
(due to snapping division variation of binary fission) cell attached at one end.
e) palisade: fence like arrangement along long axis, stacked.
Ex: corynebacterium diphtheriae (can be v shape or palisade, can also display pleomorphism)
Bacilli disease
bacillus cereus
found in spoiled food
E colli:
note:
some bacteria dont have “bacilli” in its name despite being rod shape. such as E colli.
Ex: corynebacterium diphtheriae (can be v shape or palisade, can also display pleomorphism)