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
