Micro 5 lab exam 3
AMES TEST: What is back mutation
"fixes" the mutated his gene
AMES TEST: Which contains colonies produced by induced mutations?
(+) plate
AMES TEST: Which of your plates contains colonies produced by spontaneous mutation?
(-) plate
WASTEWATER TREATMENT: What is involved in the Secondary treatment and Disinfection and release process? (2)
- Liquid from oil is called primary effluent which needs to be aerated with organic microorganisms present so they can digest organic materials - Nitrification and Denitrification bacteria are present in order to rid of nitrogen to avoid eutrophication.
CATALASE TEST: What does it mean if bacterium did not produce bubbles?
- The bacterium is anaerobic - no catalase enzyme present
TRANSFORMATION: What is calcium chloride used for? (2 things)
- creates tiny holes in cell wall - ca2+ ions are a bridge between negative (-) cell wall and negative (-) DNA
COLIFORM ANALYSIS: Which ingredients are important for the main purpose of the CONFIRMED test?
-BILE SALTS 'inhibit growth of Gram-positives' -also 'Gram-negative fecal bacteria are adapted to their presence' -BRILLIANT GREEN 'inhibit growth of Gram-positives' -BOTH INHIBIT PEPTIDOGLYCAN SYNTHESIS 'GROWTH OF GRAM POSITIVE BACTERIA'
COLIFORM ANALYSIS: If E. coli is present in the COMPLETED test, what color will you see? What does this result tell you about your water sample?
-GREEN -THE WATER SAMPLE HAS E.COLI COLIFORMS IN IT
COLIFORM ANALYSIS: What is the purpose of the lactose broth?
-Lactose as only carbon/energy source •Fecal coliform bacteria can ferment lactose to make ATP & organic molecules
WASTEWATER TREATMENT: What is involved in the Primary treatment stage process?
-Remove solids which are going to settle out as primary sludge -skim to remove grease and oil from the surface of the water
TRANSFORMATION: What are the 6 steps of artificial transformation
1. mix competent cells & plasmid DNA 2. incubate on ice 3. heat-shock 4. add LB broth 5. incubate 6. plate onto LB plates with and without antibiotic
MANNITOL SALT AGAR (MSA) TEST: What does it mean if the bacterium changes the color of the MSA?
An acidic byproduct is formed that causes the phenol red in the agar to turn yellow. (+/+)
COLIFORM ANALYSIS: Define "Coliform"
Coliform bacteria are defined as Rod shaped Gram-negative non-spore forming and motile or non-motile bacteria which can ferment lactose with the production of acid and gas when incubated
COLIFORM ANALYSIS: If your sample produced gas in the PRESUMPTIVE test what can you conclude?
GAS PRESENT: gas bubble, the broth is cloudy = growth, gram negative coliforms (but not certain they're from feces) NO GAS PRESENT: no gas bubble, clear broth, bacillus or clostridium
ENTEROTUBE TESTS: Which of the Enterotube tests involve breakdown of an amino acid?
Glucose
TRANSFORMATION: Where did the name "transformation" come from?
In the Griffith experiment the rough bacteria became smooth bacteria.
Why is the indicator organism for fecal contamination of water used?
It measures the concentration of total coliform bacteria associated with the possible presence of disease causing organisms. ... Coliform bacteria can also be found in soil/grain.
WASTEWATER TREATMENT: What is organic material?
Molecules of life with carbon-hydrogen backbones
COLIFORM ANALYSIS: What type of medium is EMB agar? (Enriched, differential or selective?)
SELECTIVE: 'selects against Gram-positive bacteria) DIFFERENTIAL: 'E. coli has unique colony morphology'
WASTEWATER TREATMENT: What stage(s) of wastewater treatment involves a Microbial process?
Secondary treatment Sludge Digestion
ENTEROTUBE TESTS: What taxonomic group of bacteria can be identified using this method?
Species and subspecies of Salmonella, E.coli, Klebsiella, and Shigella. Other disease-causing bacteria in this family include Enterobacter and Citrobacter.
AMES TEST: Explain the difference between spontaneous mutation and an induced mutation.
Spontaneous mutations arise in nature automatically, induced mutations are man-made or induced into a cell.
TRANSFORMATION: Most bacteria won't receive a plasmid, why is this?
THE BLA GENE Kill all non-transformed bacteria with ampicillin and transformed bacteria will survive.
AMES TEST: Explain how the Ames test works.
The Ames test uses an enzyme called His which makes histidine = essential amino acids. The Ames test use bacteria called salmonella typhimurium to test whether a chemical can cause mutations in the DNA of the test organism. A positive test indicates that the chemical is mutagenic and may act as a carcinogen.
WASTEWATER TREATMENT: What is nitrification?
The aerobic conversion of ammonium ion into nitrate (ammonium + oxygen --> nitrite + oxygen --> nitrate)
COLIFORM ANALYSIS: Why did we use Brilliant-Green Lactose Bile Broth for the CONFIRMED test?
The broth is a selective medium for Gram-negative bacteria and tests for lactose fermentation
TRANSFORMATION: Explain the purpose of spreading E.coli + water onto LB + Amp + Xgal plate. what did that tell us?
There should be no growth. Amp. works E.coli were not resistant to Amp. in the beginning
COLIFORM ANALYSIS: What is the purpose of Eosin and Methylene blue in this test?
They are pH indicator dyes which combine to form a purple/pink color at low pH -They also inhibit the growth of most Gram positive organisms.
AMES TEST: What is the Ames test used for?
To determine if a chemical is a mutagen
WASTEWATER TREATMENT: What is wastewater?
all water that comes from: •household drains (sink, shower, washing machine, toilet) •industrial drains (factories, etc) •storm drains (rainwater after passing over ground / roads)
WASTEWATER TREATMENT: Is the sludge digestion process of the wastewater treatment aerobic or anaerobic?
anaerobic -no oxygen present - fermentation
TRANSFORMATION: what does the bla gene stand for?
beta latamase
TRANSFORMATION: What is the name of the enzyme encoded by the bla gene?
beta-galactosidase a.k.a. beta-gal, b-gal
COAGULASE TEST: solid "gel" plasma means?
clotted plasma
MANNITOL SALT AGAR (MSA) TEST: What exactly causes the color to change?
lactic acid
CATALASE TEST: What caused the bubbles on the glass slide?
oxygen gas
AMES TEST: Which strain of Salmonella was used to detect each type of mutation?
strain M
AMES TEST: Sodium azide/ NaAz (positive control chemical) induces which type of mutation?
substitution mutations
TRANSFORMATION: What are some important uses of transformation in the lab? (3 uses)
- To make multiple copies of DNA (DNA cloning) - To make large amounts of specific human proteins, for example, human insulin, which can be used to treat people with Type 1 diabetes. - To genetically modify a bacterium or other cell
TRANSFORMATION: What are 3 features that have been engineered into pUC18 to make it useful in biotechnology?
- includes a gene for antibiotic resistance to Ampicillin - a gene (and its promoter) for the enzyme beta-galactosidase (lacZ). - In the polylinker region of the lacZ gene, with a series of unique restriction sites found nowhere else in the plasmid.
COLIFORM ANALYSIS: What ingredients are in the Eosin-Methylene Blue (EMB) agar plate for the COMPLETED test?
-AGAR -LACTOSE & SUCROSE: sugars for fermentation -PEPTONE: nitrogen source -METHYLENE BLUE DYE: inhibits growth of Gram-positives -EOSIN DYE: inhibits growth of Gram-positives; turns green/black in acidic conditions * THE 2 DYES TOGETHER: produce distinctive colony morphology of E.coli
COLIFORM ANALYSIS: What ingredients are in the Brilliant Green Lactose Bile Broth (BGLBB) for the CONFIRMED test?
-LACTOSE: as the only carbon source -BILE SALTS: inhibit growth of Gram-positives -Gram-negative fecal bacteria are adapted to their presence -BRILLIANT GREEN: inhibit growth of Gram-positives -DURHAM TUBE: to collect any gas produced
ENTEROTUBE TESTS: What other molecules does the Enterotube test for? (i.e. not a sugar, sugar alcohol, or amino acid that bacteria may be able to digest)
-Lysine, -Ornithine, -H2S, -Indol and Voges-Proskauer (VP) results are given to us - Dulcitol and Phenylalanine -Harnstoff Urea/Uree -Citrate
TSI TESTS: List ingredients in the agar and explain the relevance to the test
-PEPTONE: digested animal protein •Source of amino acids, including cysteine (but also all 19 others!) -pH INDICATOR PHENOL RED: •Yellow below 6.8, Red 6.8 - 8.4, Pink above 8.4 -3 SUGARS AS CARBON SOURCES: •0.1% GLUCOSE, 1% SUCROSE, and 1% LACTOSE -FERROUS SULFATE (FeSO4) •If bacteria can break down cysteine, they produce Hydrogen Sulfide gas •Hydrogen Sulfide gas reacts with Ferrous Sulfate (FeSO4), forming a black precipitate
COLIFORM ANALYSIS: If other coliforms but NOT E. coli are present in the COMPLETED test, what color will you see? What does this result tell you about your water sample?
-PURPLE/PINK -THE WATER SAMPLE DOES NOT HAVE E.COLI COLIFORMS IN IT
COLIFORM ANALYSIS: What was the main purpose of doing the CONFIRMED test?
-Rule out the Gram positives like Bacillus and Clostridium that can ferment lactose w/ gas production
WASTEWATER TREATMENT: What happens to the sludge involved in the Secondary treatment and Disinfection and release process?
-Some sludge will be sent to sludge digestion -Some sludge will be activated that will be sent back to the aeration tank as a source of fresh microbes. -All sludge from primary and secondary is digested anaerobically to rid of more organic material which will generate methane to power the plant - Dry out remaining sludge to compost it * If they get rid of pathogens the remaining dried sludge can be used as fertilizer
COLIFORM ANALYSIS: What is the purpose of Sucrose in this test?
-Sucrose permits early detection of coliform bacteria that ferment sucrose more rapidly than lactose. -Sucrose also helps to identify of certain gram-negative bacteria that could ferment sucrose but not lactose.
ENTEROTUBE TESTS: Why is the Enterotube test useful in hospital labs?
-The Enterotube test provides a simple, reliable, and rapid method for the presumptive identification of Enterobacteriaceae. -The major advantage of the Enterotube is that all tests are done simultaneously by inoculation from a single isolated colony.
WASTEWATER TREATMENT: How is wastewater disinfected?
-Treat with chlorine (halogen) -Filtering system -Expose to UV light -Water is tested for presence of fecal coliform bacteria
COLIFORM ANALYSIS: What other organisms can give a positive result in the PRESUMPTIVE test (besides fecal coliform bacteria)?
-bacilli: includes coliform -bacilli: includes bacilli or clostridium
AMES TEST: What would we need to do to determine if any of the chemicals (water, NaAz, and the test "round-up") we tested are human carcinogens?
1. compare people who are normally around round-up and people who aren't normally around round-up and compare results to see who has a higher rate for cancer. 2. Apply a cancer causing chemical to human or animal cells in culture and see if their cells divide rapidly and form tumors.
CATALASE TEST: What are the 4 steps for a Catalase test?
1.) Culture and obtain single colonies 2.) Gram Stain to start identification 3.) Metabolic test to complete identification 4.) Antibiotic sensitivity tests
WASTEWATER TREATMENT: What are the different anaerobic digestions going on in the Sludge Digestion phase of wastewater treatment?
1.) FERMENTATION OF REMAINING ORGANIC MATERIAL --> organic acids + carbon dioxide 2.) FURTHER FERMENTATION OF ORGANIC ACIDS --> carbon dioxide + hydrogen gas 3.)ANAEROBIC RESPIRATION (by archaea called methanogens) 4H2 + carbon dioxide--> CH4 + 2H2O (methane and water)
WASTEWATER TREATMENT: What are the steps for water treatment? (4)
1.) Primary treatment 2.) Secondary treatment 'biological oxidation' 3.) Disinfection and release 4.) Sludge digestion
TRANSFORMATION: What is the definition of Transformation?
A bacterial cell takes up DNA from outside the cell. dead cells leave DNA behind
TRANSFORMATION: What is bacterial plasmid?
A plasmid is a small, circular, double-stranded DNA molecule that is distinct from a cell's chromosomal DNA. Plasmids provide bacteria with antibiotic resistance.
TRANSFORMATION: What is a Vector?
A vehicle to carry genes into cells
ENTEROTUBE TESTS: Which of the Enterotube tests involve fermentation of sugars or sugar alcohols?
Adonitol, Lactose, Arabinose and Sorbitol
WASTEWATER TREATMENT: What is Denitrification?
Anaerobic respiration using nitrate as final electron acceptor then generates into nitrite/nitrogen gas, released into air
AMES TEST: What are back mutations?
Bacteria regain ability to grow on MM plates because they can make their own histidine
TRANSFORMATION: What is competent bacterium?
Bacteria that are able to take up DNA
TSI TESTS: What is the purpose of the butt in the agar in the TSI test?
Bottom part of agar that excludes air/oxygen -Fermentation of sugars -Breakdown of cysteine to form Hydrogen gas
AMES TEST: Explain how the CM plates and MM plates differ from each other.
CM plates contains histidine so bacteria can grow and MM plates do not so bacteria cannot grow
WASTEWATER TREATMENT: What are the end products of Sludge Digestion? (2)
Carbon dioxide gas and Methane
MANNITOL SALT AGAR (MSA) TEST: If an unknown bacterium is a Gram-positive coccus but not halotolerant, what additional tests could you do to identify the species?
Catalase test
TRANSFORMATION: What are the differences of Linear and circular DNA?
Circular DNA can come into the cell and maintain as a circular plasmid and does not need to integrate into the chromosome. Linear DNA will be degraded if it doesn't get integrated into the chromosome
COAGULASE TEST: Explain how the coagulase test works
Coagulase is an enzyme produced by Staph. aureus that converts fibrinogen in plasma to fibrin.
COAGULASE TEST: Explain why possession of coagulase enzyme would make a bacterial species more virulent
Coagulase is bound to S. aureus and coats its surface with fibrin upon contact with blood. The fibrin clot protects the bacterium from phagocytosis and isolate it from other defenses of the host. THE FIBRIN COAT can therefore make the bacteria more virulent.
COLIFORM ANALYSIS: What is the purpose of Lactose in this test?
Coliform bacteria rod-shaped Gram-negative nonspore forming and motile or nonmotile bacteria that can ferment lactose with the production of acid and gas
TRANSFORMATION: What is required for a bacterium to be able to do transformation?
Competence: Able to take out large DNA from it surroundings
COLIFORM ANALYSIS: What is the purpose of the Agar in this test?
Culture media, agar plates inhibit the growth of gram positive bacteria and only allow the test to determine their presence of gram-negative bacteria capable of fermenting lactose.
TSI TESTS: Hydrogen Sulfide gas is produced from the breakdown of which sulfur-containing amino acid?
Cysteine = black color
TRANSFORMATION: Explain how we could use a plasmid like pUC18 to make bacteria that produces a human protein, such as insulin, for use in medicine.
DNA cloning: - Cut open the plasmid and paste in the gene. This process relies on restriction enzymes (which cut DNA) and DNA ligase (which joins DNA) - Insert the plasmid into bacteria - Grow up a lot of plasmid-carrying bacteria and use them as factories to make the protein.
TRANSFORMATION: How do you distinguish recombinant plasmids from non-recombinant plasmids?
Different colored colonies. If the plasmid is non-recombinant, lacZ is intact and will have blue colonies If the plasmid is recombinant, LacZ has been disrupted and cannot function to make blue colonies therefore the colonies turn white.
WASTEWATER TREATMENT: How do we get rid of Eutrophication?
Digestion by aerobic microorganisms
TRANSFORMATION: How does the pUC18 plasmid work?
Digestion with any one of these endonucleases will make a single cut that linearizes the circular plasmid DNA, and allow it to recombine with foreign DNA that has been cut with the same endonuclease.
WASTEWATER TREATMENT: What stage(s) of wastewater treatment involves a Chemical process?
Disinfection and Release
CATALASE TEST: What is the purpose of a Catalase test?
Distinguishes aerobes vs. anaerobes
COLIFORM ANALYSIS: Explain why E.coli and E.aerogenes bacteria looks different from each other?
E. COLI: metallic green = fermentation of sugars creates A LOT of acidic byproducts E.AEROGENES pink/purple = fermentation of sugars creates SOME acidic byproducts
COLIFORM ANALYSIS: What unique metabolic trait of E. coli is relevant to the COMPLETED test?
E.COLI IS METALlIC GREEN
TRANSFORMATION: Explain the purpose of the LB plates w/out Amp. What do they tell you?
E.coli are viable, LB plates have nutrients to support E.coli
TRANSFORMATION: Explain why there are fewer colonies on the LB + Amp + X-gal plate spread w/ E.coli + plasmid than on the LB plate spread w/ the same cells
E.coli is sensitive and die in the presence of ampicillin and we didn't give them an ampicillin resistant gene, we gave them water. No DNA are going to be taken up by them and as a result they die.
WASTEWATER TREATMENT: What is involved in the Disinfection and Release process?
Effluent from secondary treatment goes into disinfection and release using UV light, filtering and chlorination.
ENTEROTUBE TESTS: What are some metabolic characteristics that the Enterotube tests for?
Enterobacteriaceae of: -GRAM-NEGATIVE, -facultatively anaerobic, -NON-SPORE-FORMING RODS, -MOTILE, -catalase positive, -oxidase negative, -reduction of nitrate to nitrite -acid production from glucose fermentation
AMES TEST: How would we test if Round-Up causes cancer?
Expose chemical over a long period of time to an animal that could get cancer
AMES TEST: How would we test if Round-Up is toxic to humans?
Expose human cells to chemical to see if the cells die or use an animal similar to humans to test the lethal dose.
CATALASE TEST: What are metabolic test used for?
Metabolic tests allow you to positively identify species from one another
TRANSFORMATION: The plasmid vectors don't always take up the inserted gene,What is a solution?
Multiple cloning sites with in LacZ gene
COLIFORM ANALYSIS: What should a positive and negative result confirm in the COMPLETED test?
NEGATIVE OPTION 1: -No growth on plate = no Gram-negative bacteria present -No E. coli or fecal coliform bacteria present NEGATIVE OPTION 2: -Colonies are colorless = no fermentation of sugars to lower pH of agar -Gram negatives, but no E. coli or fecal coliform bacteria present NEGATIVE OPTION 3: -Colonies are pink/purple = fermentation of sugars creates some acidic byproducts = lower pH of agar = slightly changes color -Likely coliform bacteria other than E. coli (such as E. aerogenes) POSITIVE: -Colonies are metallic green = fermentation of sugars creates a lot of acidic byproducts = lower pH of agar = changing colonies' color -E. coli present
COLIFORM ANALYSIS: What are the negative and positive results for the PRESUMPTIVE test?
NEGATIVE: 1.) No growth in test tube 'no organisms in water that can metabolize lactose' -OR- 2.) Growth but NO gas trapped in Durham tube = no gas produced from fermentation of lactose 'organisms in water that can metabolize lactose but not gas' -No fecal coliform bacteria present POSITIVE: 1.) Growth in test tube AND presence of gas trapped in Durham tube = gas produced from fermentation of lactose -Possible presence of fecal coliform bacteria and continue with Confirmed test
COLIFORM ANALYSIS: Does a positive PRESUMPTIVE test indicate definite evidence of fecal contamination of a water sample? Why/ Why not?
NO - because a positive test can indicate possible presence of fecal coliform bacteria and continue with Confirmed test -other bacteria 'Gram positives such as Bacillus and Clostridium' can also ferment lactose & produce gas
WASTEWATER TREATMENT: What is Eutrophication?
Nutrients in a body of water that causes a dense growth of plant life and death of animal life from lack of oxygen. i.e. Nitrogen from aerobic respiration in the secondary treatment.
COLIFORM ANALYSIS: What is the purpose of Peptone in this test?
Peptone is peptic digest of animal tissue and sodium chloride. Peptone is a non-selective broth medium
WASTEWATER TREATMENT: What stage(s) of wastewater treatment involves a Physical process?
Primary treatment
WASTEWATER TREATMENT: What are some Aerobic microorganisms that clean wastewater?
Protists such as Ciliates, Small animals such as Rotifers, and Prokaryotes such as Amoeba
WASTEWATER TREATMENT: What is effluent?
Remaining liquid from the primary sludge pumped to another tank for secondary treatment
WASTEWATER TREATMENT: What is the goal of the primary stage of wastewater treatment?
Remove solids and floating grease / oil -skim surface of water -allow solids to settle in bottom of sedimentation tanks
AMES TEST: How can back mutations occur?
Round-up caused a mutation = mutagen and MAKES A LOT OF RANDOM MUTATIONS IN BACTERIA'S GENOME
MANNITOL SALT AGAR (MSA) TEST: What/Where are the natural habitats of the specific bacteria used for this test?
S aureus is in the skin, GI tract and nose S epidermidis is all over the body including skin
COAGULASE TEST: What does this test tell you about the two STAPHYLOCOCCUS species?
S. aureus produces free coagulase S. epidermidis does not.
COLIFORM ANALYSIS: What type of medium is used in the PRESUMPTIVE AND CONFIRMED test?
SELECTIVE 'for gram negatives'
COLIFORM ANALYSIS: What kind of medium is in the COMPLETED test
SELECTIVE 'selects against Gram-positive bacteria' DIFFERENTIAL 'E. coli has unique colony morphology'
MANNITOL SALT AGAR (MSA) TEST: The high concentration of salt in the medium is selective for what general type of bacteria?
Salt- tolerant (HALOTOLERANT) BACTERIA STAPHYLOCOCCI
MANNITOL SALT AGAR (MSA) TEST: Mannitol-salt agar (MSA) is what type of medium?
Selective and Differential
TSI TESTS: Explain why there is a lower concentration of glucose in the agar than lactose and sucrose
So we can determine if our bacteria only ferment glucose or if they can also ferment other sugars as well --> glucose runs out after about 10 hours, bacteria that ferments glucose only will aerobically break down peptone 'slant only' which produces alkaline byproducts that turn slant red
MANNITOL SALT AGAR (MSA) TEST: List all the tests needed to determine that the organism is a pathogenic STAPHYLOCOCCUS species.
The coagulase test catalase-positive cocci Mannitol fermentation
What does the Coagulase test for?
The coagulase test is useful for differentiating potentially pathogenic Staphylococci such as Staphylococcus aureus from other Gram positive, catalase-positive cocci.
TRANSFORMATION: What is meant by the term "recombinant plasmid"
The foreign DNA will be replicated by bacterial enzymes along with the carrier plasmid and any genes present can be transcribed and translated.
COLIFORM ANALYSIS: Why do we test water for Coliforms?
The presence of coliform bacteria in drinking water indicates pathogens could be in the water system.
COLIFORM ANALYSIS: What is the indicator organism for fecal contamination of water?
The total coliform bacteria test is a primary indicator of "POTABILITY" , suitability for consumption, of drinking water.
CATALASE TEST: What is/are the difference(s) between anaerobic respiration and fermentation?
They both begin with Glycolysis but the end of anaerobic respiration creates pyruvate and then continues on the same path as aerobic respiration. Then the citric acid cycle and Oxidative Phosphorylation. The second and last step of fermentation is NADH regeneration.
COAGULASE TEST: What is the purpose of thrombin?
Thrombin converts fibrinogen into fibrin, (along with platelets) are our blood clots
WASTEWATER TREATMENT: What is the goal of the secondary stage of wastewater treatment?
To break down as much organic material in effluent as possible
COLIFORM ANALYSIS: What was the main purpose of doing the COMPLETED test (EMB)?
To confirm the presence of indicator fecal coliform bacteria E. coli -There could also be Enterobacter aerogenes, a coliform that is not necessarily from feces (also be found in soil/grain)
ENTEROTUBE TESTS: What is the Enteropluri test used for?
To identify Enterobacteriaceae and other gram negatives
COLIFORM ANALYSIS: What is the purpose of the brilliant-green lactose bile broth?
To rule out gram positives
TSI TESTS: What is the purpose of the slant in the agar in the TSI test?
Top part of agar that is exposed to air/oxygen -Aerobic respiration using sugars and amino acids from peptone
TRANSFORMATION: What is bacterial transformation?
When DNA is taken directly from the environment and the bacteria acquire observable new traits.
MANNITOL SALT AGAR (MSA) TEST: Can you relate the habitat of the bacteria to the ability to grow on MSA plates?
YES, since the MSA test is used to determine if the bacteria is halophilic (salt loving) and if the bacteria can ferment mannitol. If the bacteria is able to grow then it is a halophilic bacteria, DUE TO IT'S ABILITY TO GROW IN A HIGH SALT ENVIRONMENT
AMES TEST: Explain what the CM plates (toxicity test) tell you about each of the chemicals used: Is there a zone of inhibition? a.)water (-) b.) NaAz (+) c.) and the test "round-up"
a.) No spontaneous back mutations, No zone of inhibition b.) No induced mutations, No zone of inhibition c.) Yes, there is a zone of inihibition
AMES TEST: Explain what the MM plates (Ames test) tell you about each of the chemicals used: Were there any mutagens present? a.)water (-) b.) NaAz (+) c.) and the test "round-up", what is the reasoning behind your result?
a.) little to no mutagens b.) mutagens present c.) little to no mutagens. Round-up does not cause substitution mutations.
AMES TEST: a.) Did "round-up" cause mutations? b.) Explain how you know.
a.) little to no mutagens b.) there is a zone of inhibition
WASTEWATER TREATMENT: Is the secondary wastewater treatment process 'biological oxidation' aerobic or anaerobic?
aerobic
TRANSFORMATION: There are bacterial colonies growing on the LB + Amp + Xgal plate spread w/ E.coli + plasmid. What has happened to these bacteria to allow them to grow in the presence of Amp.?
beta-lactamase released by the bla-expressing colony degrades the ampicillin in the vicinity of the colony.
TRANSFORMATION: How can a researcher determine if cells w/in a colony contain a recombinant plasmid?
by screening for the insertional inactivation of a second genetic marker on the plasmid.
WASTEWATER TREATMENT: What are the end products of aerobic respiration?
carbon dioxide and water
CATALASE TEST: Why does hydrogen peroxide bubble if you put it on a skin cut, or use it on your teeth?
catalase attacks hydrogen peroxide and converts it into water and oxygen
TSI TESTS: What is the TSI test used for?
distinguish gram negative bacilli from each other a.k.a "enteric bacteria" named for its ability to test a microorganism's ability to ferment sugars and to produce hydrogen sulfide gas
COLIFORM ANALYSIS: What are the fermentation end products made by E.aerogenes bacterium?
lactate, acetate, ethanol, succinate, formate, carbon dioxide gas and hydrogen gas.
COLIFORM ANALYSIS: What are the fermentation end products made by E.coli bacterium?
lactate, acetate, ethanol, succinate, formate, carbon dioxide, and hydrogen.
COLIFORM ANALYSIS: What are the ingredients of the medium for the PRESUMPTIVE test?
lactose broth containing: -LACTOSE as only carbon/energy source •FECAL COLIFORM BACTERIA can ferment lactose to make ATP & organic molecules
TRANSFORMATION: What does the bla gene do?
makes cells resistant to Ampicillin
COLIFORM ANALYSIS: What do E. coli colonies look like on EMB agar?
metallic green/black
AMES TEST: How are the terms mutagen and carcinogen related?
mutagens change/mutate the DNA, while carcinogens can mutate DNA which lead to cancer.
WASTEWATER TREATMENT: The conversion of ammonia to nitrate is known as?
nitrification
COAGULASE TEST: liquid plasma means?
plasma that did not clot
CATALASE TEST: What is the purpose of catalase in cells?
protecting the cell from oxidative damage by reactive oxygen species (ROS).
COLIFORM ANALYSIS: What do E. aerogenes colonies look like on EMB agar?
purple/pink
WASTEWATER TREATMENT: What is the goal of wastewater treatment?
remove waste and as much organic materials we can from the wastewater before we release it into the environment
WASTEWATER TREATMENT: What is primary sludge?
settled solids in the water
ENTEROTUBE TESTS: Give 3 characteristics of taxonomic bacteria
shape 'vibrio, bacillus, coccus etc.' presence of endospores, gram stain, aerobic conditions, and motility.
COAGULASE TEST: What is the human enzyme used in this test?
thrombin
TRANSFORMATION: When does bacterial transformation occur in nature?
when developing antibiotic resistance, bacteria then shed their resistant even to another one (horizontal transmission).
TRANSFORMATION: What does beta-galactosidase do?
when the enzyme catalizes the reaction X-gal (the substrate) is put onto agar plates. X-gal + B-gal = blue bacteria, Nonrecompinant plasmid w/lacZ intact = blue bacteria Recompinant plasmids lacZ were cut in half = white bacteria
CATALASE TEST: What is/are difference(s) between aerobic and anaerobic respiration?
whether or not oxygen is present. -aerobic = carbon dioxide, water, and ATP are produced - anaerobic = lactic acid, ethanol, and ATP are created.
COLIFORM ANALYSIS: What is the purpose of the Durham tube?
•Lactose fermentation by fecal coliform bacteria produces gas 'carbon dioxide' as a byproduct •Gas is collected