Micro - lab exam 2 Flashcards
sulfur is..(F is…)
antimetabolite. it stops the synthesis of folic acid
Protein synthesis - tetracyline (tetris - kitchen)
wedges in between anti-condon and codon. it stops the interaction on messenger RNA and transfer RNA. they must match.
ciprofloxin targets..
nucleic acid and DNA replication
target..cell wall peptidoglycan (3 total)
penicillin, vancomyocin and bacitracin
targets protein synthesis - targets ribosomes (3 total) (baseball)
tetracyline, neomycin, chloramfinenicol, eyrthromyocin target..
thymine dimmers (A and T)
A pairs with T, and G pairs with C, which consists of a hydrogen bond. When exposed to UV light, the bond between A and T breaks, and covalent bonds between the two Ts on the same strand. The covalent bond is the thymine dimmer. This causes a disruption to the replication and transcription DNA, and there is no messenger RNA, no protein synthesis, and there is no bacterial cell multiplication. The cell then dies
The light repair uses…
photolyze enzyme, which breaks thyamine dimmers and restores A and T bond.
dark repair
The enzyme excisase chops away the DNA with thyamine. The complimentary DNA uses the other strand as template. Once it is formed, it will join the new strand and old strand. They are then glued together by the DNA ligase.
citrate test used to..
determine if bacteria can use sodium citrate as a carbon source
medium for citrate test
Simmon’s citrate medium
simmons medium for citrate test is composed of..
sodi citrate - carbon source
ammonium phosphate - nitrogen and phosphorus source
ph indicator - citrate
bromothymol blue
bacteria in citrate gets basic ph because….(basic blender)
bring in sodium citrate, produce citrase, coverts pyruvate through decarboxylation for the Kreb’s cycle. CO2 combines with sodium to form sodium carbonate and sodium bicarbonate.
indole test is used to dermine if…
bacteria synthesizes tryptophanase. The purpose is to determine if the bacteria can produce idole.
Kovac’s test - reagent
reagent contains dimethylaminobenzaldehyde hydrochloride, and amyl alcohol.
MR test is determine…(rogers)
stable vs unstable acids of metabolism by intestinal bacteria. Sugars are metabolized and make acids, and the acids could be either stable or unstable.
VP test reagents
VP1 and VP2 reagents added into smaller tubes. VP1 is alpha naphthol, VP2 is potassium hydroxide.
coliforms are
gram negative facultative rods that are non-spore formers. They ferment lactose sugar, producing acid and gas. They are mainly intestinal bacteria.
The presumptive test uses…and it tests for what…
a lactose broth, and it tests water for the presence of fecal coliforms.
Durham tube - presumptive test (durham - game)
it is inside the lactose broth. The Durham traps gas that is released from lactose metabolism
results of citrate test (color)
The dye turns into a dark blue color (Prussian blue), and it indicates that the bacteria has used citrate as a carbon source. If it is not blue, it is citrate negative and will appear green
kovac’s test (indole test) - results
If the bacteria is making tryptophans, the pink part floating on the top means its indole positive.
voges test procedure and results (kam)
The VP1 reacts with acetoin and forms a colorless complex. That complex combines with peptones. red is vp positive.
Balantidium coli - Trophozoite feature
motile with macro and micronucleus
Disease and diagnosis: Balantidiasis
Identifying cysts or trophozoites in feces ; mostly asymptomatic infection
Cryptosporidium causes (disease and symptoms)
Cryptosporidosis of immunocompromised (HIV) individuals and digestive system with diarrhea
Diagnosis Cryptosporidosis
finding oocysts in feces
Trichomonas sps - infected organs (male, female) VVC and SUP
males: urethra, prostate and seminal vesicles
Females : vagina, vulva and cervix
do trichomonas produce cysts?
No
Transmission: sexual intercourse (direct transmission)
Leishmania sps (thai and..)
in tropical and subtropical areas
progressive fatal disease if left untreated
Leishmania sps - lesions are on..(SPON)
kala azar, skin. oral, nasal, pharanygeal. mucous membrane inflammation.
Leishmania sps transmission
bite of sandflies as well as direct contact with lesions
Which human tissues are infected with Plasmodium sps ?
RBC’s, liver and spleen ( completes its asexual phase in invertebrates)
What’s the ring stage Plasmodium sps ?
TROPHOZOITE stage
Where does Plasmodium sps complete the ring stage ?
RBC’s
Vector for transmission trypanosoma
Tse tse fly ( Glossina sps)
Nucleic acid - Ciprofloxacin targets… (flax - rubber band)
the bacterial DNA or RNA synthesis. DNA gyrase cuts the separated strands of DNA and removes the stress between the separated strands.
Mc Conkey - agar medium is…
selective and differential.
hydrolyzed proteins in Mc Conkey are (bread - corner)
the peptones that used as a carbon source for non-fermenting bacteria
E.coli - pink due to….- Mc Conkey (monkey - plant)
stable acids that have run across the entire medium. As the pH gets lower (becomes acidic), it forms pink colonies
What happens to amino acids used by Pseudomonas and Proteus in Mc Conkey (king - kitchen table)
the amino acids undergo deamination. The ammonia has to be removed, and the carbon skeleton enters the Kreb’s cycle. The ammonia causes the pH to become alkaline, which turns the pH indicator yellow or colorless.
Urea - proteus
Proteus makes the urease and it will break down urea so quickly the phosphate will resist the pH change. Such a large amount of ammonia is produced, and the phosphate buffer is overridden and it turns pink.
Pseudomonas in the nutrient agar plate are always….(keylime)
a bluish green teal color of bacteria. The smell sweet and runny colonies. The greenish color is due to a pigment called pyocyanin.
methyl red test - stable acids will turn…
the methyl red will turn red under the acidic ph.
vp test - unstable acids (color)
If the medium has unstable acids, it will turn yellow.
voges - If it is MR positive…
it is always VP negative because it doesn’t make butanediol. If it is MR negative, it has to be VP positive.
trichomonas - Disease and the pathogen
asymtomatic or mild trichomoniasis (inflammation of the eurogenital mucosal membrane) by T vaginalis
dimethylaminobenzaldehyde hydrochloride - kovak’s test (dime)
reacts with free indole, released from tryptophan, which forms a pink complex, done under acidic conditions. The acidic condition is from the hcl.
Kovak’s reagent- the Hcl and amyl alcohol provide what?
the Hcl provides the acid condition. The amyl alcohol allows for the complex to float on the surface of medium concentrates.
unstable acids in VP test (clare - unstable)
they get further metabolized to butanediol, and there is an intermediate called acetone. If there is acetoin, it means butanediol is the dominant path
if ammonium salts are used in citrate test it forms…
ammonia and ammonium hydroxide. This creates an alkaline condition in the medium.
Transmission of the cyst - balantidium
via contaminated water
plasmodium - the vector for transmission
female Anopheles (couples sexual phase of its lifecycle) mosquito
Mc Conkey medium contains (monkey medium)
lactose sugar, which some intestinal bacteria can ferment, and some cannot ferment it
ph indicator under basic (alkaline) (high ph) conditions - Mc Conkey
turns yellow or colorless
what is generated in gas pak
h20 gas and CO2 generated inside chamber. can be noticed as moisture inside.
silver nitrate - antimicrobials
denatures the protein, called the oligodynamic action. It is used to clean the eyes of newborns to prevent neonatal ophthalmia gonorrhea, but that practice has stopped. We use a 1% solution.
Lysol and lab germicide (phenom - O)
They are phenol based antibacterial agents, or altered phenol molecules. Some may be connected by an oxygen atom, or three chlorine, called Triclosan. Triclosan was used in soaps, but it is non-biodegradable.
The action of chlorine is it is…(ox - water)
a strong oxidizing agent, and when it is dissolved in water, it forms hypochlorous acid, which forms hypochloride ion, a strong oxidizing agent.
Clorox is an…(tiny clorox)
antimicrobial activity. Hypochlorite ions are a strong oxidizing agent.
The action of Betadine (red)
as an antibacterial agent is due to the iodine, but we do not know its exact mode of action.
complex media (borrow from complex)
are rich in nutrients, they contain water soluble extracts of plant or animal tissue (eptone and tryptone). Usually a sugar, often glucose is added to serve as the main carbon and energy source
defined media (pure)
usually composed of pure biochemicals off the shelf
citrate medium does not contain
peptones or glucose
citrate uptake is due to
activity of citrate permease. allows citrate to go from outside to inside bacteria.
citrate breakdown is due to
citrase-allows it go from 6-carbon to 4-carbon acetate.
as the ph goes up (citrate) (blue mountain)
dye turns blue
tryptophan in medium from (indole test) (bank)
peptones of caesin digest. caesin is a milk protein.
kovac’s test - if there is no pink
it is indole negative
hydrogen peroxide..susceptible
H2O2 (hydrogen peroxide) is a strong oxidizing agent. Anaerobic bacteria are susceptible, and they do not have a catalase or peroxidase to break down water
gas pak strip is…(first color)
A methylene blue strip placed inside the gas-pak will remain colorless if the environment is anaerobic, but it will turn blue if it is exposed to oxygen.
gas pak reaction is initiated…
when the gas pak is opened. The sodium borohydride and the sodium bicarbonates combine to form H2 gas and carbon dioxide. The H2 gas and oxygen combine to form H20, which reacts with the palladium catalyst. The H20 can be noted as moisture condensation inside the chamber.
lysol and lab germicide dissolve…
lipids and denature protein
simple media
used for the primary isolation of microorganisms
The selective factor Mc Conkey
the bile salts because they only support growth of enteric bacteria, and the crystal violet dye which only supports growth of gram negative
differential factor Mc Conkey -
can it ferment lactose or not
mannitol salt agar medium is…(salt on leg)
selective and differential for isolation and detection of staph species.
mannitol salt - selective factor
sodium chloride
use a toothpick for oxidase test because
metal will give a false positive due to the electron acceptors
S. aureus - mannitol (aura)
is an opportunist microbe in nasal. It does ferment mannitol. if there is a halo, that is the mannitol fermentation.
S.aureus results - mannitol (color and size)
yellow colored colonies, and they are bigger compared to S epidermidis. is capable of fermenting mannitol
S pyogenes - blood agar
S pyogenes secretes hemolysin. You can see a halo around the colonies due to the beta hemolysin.
Staphylococcus epidermitis - mannitol (epi - gentle)
is not capable of fermenting mannitol. This is a differential medium
mannitol medium - (medium salt)
Mannitol salt - 7.5%, which is inhospitable for most bacteria except Staphylococcus.
if there is a halo it is____and the color is____
acidic and agar turns yellow.
what makes mannitol salt a complex medium?
the PEPTONES and the extract.
mistake in lab..
didn’t flame sterilize a second time
Most non-pathogenic staphylococci will not…
ferment mannitol.
ph indicator contains…- mannitol medium
The pH indicator contains extracts and peptones.
nutrient agar - mannitol medium (easy)
The nutrient agar makes it easy to see the difference between the two bacteria.
antibiotic that attacks protein synthesis (baseball)
tetracyline neomycin, chloramfinenicol
mc conkey under basic (alkaline) conditions turns..
yellow
DNA viruses ex. (HHH)
herpes virus family, HPV, Hep B virus.
RNA viruses ex. (CCH)
sars covid, common cold, the virus, HIV
Note about viruses (gnome)
they are unique in biological world containing RNA as genome *complex macromolecular assemblies
Central Dogma of Life (of Mol Biol) (court first)
transfer from DNA to RNA then to protein. transfer - transcription and translation - occurs in cytoplasm
Viruses break the rule of central dogma.
reverse transcription have RNA genome. Usually goes DNA to RNA, RNA to protein (normal conditions) Reverse transcriptase is RNA can’t be translated to proteins. So it goes RNA and makes copy of DNA (reverse transcriptase) then RNA, then RNA to RNA protein. dogma broken by central viruses.
Non-Enveloped (Naked virus) ex. (mark)
e.g. Rotovirus, Poliovirus.
RNA and RNA polymerase for replication of the RNA genome.
envelope viruses ex. (HIC)
HIV, Influenza, Covid-19.
stages of phage replication (me-sf)
1) attachment 2) penetration 3) genome replication 4) synthesis - transcription and translation 5) packaging and assembly (little blue things) 6) lysis - release of new virus particles
factors that influence zone of inhibition (CCDS W) (tight rope)
weight, stability, concentration of agent, density of bact. cells, characteristics of agen.
mannitol salt - differential factor (red sugar)
mannitol sugar and phenol red ph indicator
+ strand can act as an..(immediately)
mRNA and it is immediately translated by ribosome
-strand RNA can’t..
be immediately translated. it has to be made into complimentary + strand RNA
HIV - Spike proteins (encoded)
HAVE GLYCOPROTEINS
ACtivate immune system. Encoded by viral genome ; helps in attachment to host cell surface
HIV - Nucleocapsid/capsid (mirror)
Made up of capsomeres; protects viral genome.
HIV - Envelope virus (flower - physio)
Mainly phospholipid bilayer; acquired from host cell during the budding off process.
HIV - RNA genome (unique)
HIV is diploid virus. Each particle has two copies of it’s genome
HIV - Matrix proteins (the matrix)
Proteins encoded by viral genome to prevent collapse of envelope on nucleocapsid
HIV - Reverse transcriptase
RT RNA —-DNA — RNA —– protein
Covid/Flu - envelope virus - spikes have..
glycoproteins
Covid/Flu - RNA genome (hap - neg)
Haploid only (one copy) - negative strand - RNA dependent RNA polymerase. NO DNA to RNA.
Covid-19 is the…
longest viral genome to date (30000 RNA bp) Poliovirus, long genome (7500 bp)
no envelope
phages
phages - head (cap)
made of capsid which protects the viral genome (DNA/RNA)
phages - tail fibers not…
motility appendages
phages - lysozyme (cleaners)
Present at tip of tail fibers ; weakens the
bacterial (host) cell wall breaks glycosidic bonds of NAG-NAM
phages - tail (scorpion)
surrounds hollow tube and contractile sheath - helps in injecting the genome in the host cell.
Phages have either…
RNA/DNA as their genetic material BUT replication in this model is always
referred to as genome replication. Because:
1) If DNA genome: it will synthesize
DNA - RNA - proteins.
2) If RNA genome: it will synthesize RNA - Proteins.
phages do not have…
reverse transcriptase
cell lysis - phages (#)
Infected cell is lysed and virus particles are released. Each cell can release between 50-500 virus particles
no peptones/amino acids in…
citrate test bc amino acids have carbon and you are trying to see if bacteria will use citrate as a carbon source.
breakdown products of tryptophan (pineapple in egypt)
indole, pyruvic acid, ammonia
conidophore are__and looks like (con)
aspergillus - broomstick
sporangium looks like
top of lolipop. not fluffy.
sporangiophore looks like (phore)
stick of lolipop
zygospore looks like
fly
asperigiilus condidiophore looks like
dandylion or fan. these are fluffier than sporangiophores.
positive indole test Kovak (color)
pink/red
purpose of Mc Conkey
designed to isolate and differentiate enterics based on their ability to ferment lactose
if you detect butanediol, then it’s…
unstable. it will be EASILY detected by VP test.
requires constant shaking of tube
VP test
unstable acids in methyl red test will be…
yellow, and therefore VP positive bc they contain butanediol.
presumptive test is just…
adding pond water to durham tube. Then you do the confirmed test.
confirmed test is done…
on the EBM agar plate.
2 life cycles in protazoa
multiply stages (e.g., trophozoites) and dormant cysts.
Tetracycline, chloramphenicol and erethryomcyin act on protein synthesis due to…
structural differences of ribosomes, 70s versus 80s
chloramphenicol acts on larger….(flora - large pep)
subunit and stops peptide bond formation.
penicillin is a ___spectrum antibiotic.
narrow
Vancomycin is a ___spectrum antibiotic.
narrow
vacomycin binds..(vans)
to the fourth amino acid of the tetrapeptide chain, and the cross bridge cannot form.
Bacitracin inhibits…(tracy - pep)
transport of the peptidoglycan cell wall components across the plasma membrane
chloramphenicol acts on…(flora)
larger subunit and stops peptide bond formation.
neomycin targets..(fingers)
bacterial ribosomes and inhibiting protein synthesis. attacks e.coli
The folic acid is used by bacteria for…(sulfa)
DNA and RNA, and the carbon skeleton is from the folic acid. PABA is made into dihydrofolic acid, which becomes tetrahydrofolic acid, which provides the carbon skeleton to purine and pyrimidine bases. If there is no folic acid, there is no N2 base, no DNA and RNA replication, and no bacterial division
(Mc Conkey) Unstable Enterobacteria makes…(monkey - bute)
butanediol. With enterobacter, the acid is formed momentarily, and it gets broken down to butanediol. The acid is immediately broken down. it still ferments lactose though.
components of urea broth…(YUPP)
urea, yeast, phosphate, and the ph indicator.
Mc Conkey test is done to…
detect enteric bacilli - lactose fermenting gram negative rods
Mc Conkey agar has..(LB CPP)
peptones, lactose sugar, bile salts, crystal violet and ph indicator
if Mc Conkey is pink or red…
it is acidic and it ferments lactose. this is e.coli and e. erogenes
e.coli in mc conkey forms___acids
stable
enterobacter in mc conkey forms___acids
unstable
pseudomas and proteus do not ferment lacose sugar. Instead they use…
the amino acids of peptones
urea test is determine..
slow urea producers v. fast urea producers
Biological transmission occurs from…
a bite from a vertebrate or invertebrate, and examples include Dengue virus, West Nile, and Plasmodium
UV radiation experiment uses…
non-ionizing UV radiation
non-ionizing is used in..
medical facilities. makes new bonds and bacteria can’t grow.
UV exposed side..
has no growth. bacteria killed.
b. cereus withstood the uv rays better than serratia because
because it is a soil bacteria - constantly exposed to uv rays of sunlight
zone of inhibition - high molecular weight =
less killing of bacterial cells and smaller zone of inhibition
don’t put zero for the..
zone of inhibition. you still have to put the diameter of the disc. so if it’s 8, put 8.
phenol coefficient is the..
phenol used a standard for reference. it is 1.
chlorine and iodine is..
betadine
halogen containing antibacterials
chlorine and iodine
2 fungi nucleus fuse and form a
zygote. that transforms into a fruiting body.
fungi have sexual and
asexual repro. 2 hyphae come close (conjugation), cytoplasm mixes, nucleus fuses.
conidium (fruit basket)
fruiting body on conidophore. they are the fluffy part on top with the spores
rhizopus is __and it looks like___
zygospore, and it looks like a fly
rhizopus fruiting body is the..
sporangium
ending in “phore” is the..
stick part of both sporangium and conidium
vehicle transmission - FAWB
indirect - water, body fluids, food, airborne
vector
mechanical and biological
mechanical vectors and ex. of diseases (mechanic mary)
house fly transmits typhoid and dysentery pathogen off the feces of infected peoples to food ants, cockroaches etc
Antibiotics
Substance produced naturally in minute quantity by some microbes that has the potency to inhibit growth or kill other microorganisms.
Semisynthetic antibiotic
antimicrobial agent part synthesized in lab and part synthesized in microbe.
ex of Semisynthetic antibiotic (warren)
doxycycline, methcillin, ampicillin, amoxycillin
advantages of semi-synthetic
more effective against gram negative, long lasting, easier to adminster
Synthetic (antimicrobial) drug
antimicrobial agent synthesized in laboratory.
ex of synthetic drugs (IS)
isoniazid, sulfa drugs
isoniazid
for TB, targets mycolic acid
phenol red ph indicator - which tests
presumptive/confirmed and mannitol tests
peptones in mannitol salt…
can be a source of carbon for some bacteria like Staphylococcus epidermidis. The peptones are used first and they are deaminated, which creates slight alkaline conditions.
MR turns yellow…
the pH is above 6.0 and the mixed acid fermentation pathway has not been utilized
vp positive is (color)..and it means…
red, and it means butanediol is present.
lactose and hydrolyzed proteins in mc conkey are the..
differential factors
ph indicator under acidic conditions - Mc Conkey
turns pink/red
phage - packaging and assembling
viral proteins assemble and pack the viral genome and inside host cells
