Test 3 Flashcards
pathogen that’s an ex of antigenic variation
influenza virus
application of medical/red biotechnology
microbe is used as host for making recombinant human protein
metagenomics
process where DNA is extracted from the whole environmental sample and is used to construct a genomic library; they are identified, screened, and compared to others; mainly analyze 16S rRNA because they are domain specific; it is very energy intensive and we can understand what the community is made of without any culturing
difference between fed-batch reactors and chemostats
fed batch: nutrients are added all at the beginning, then it’s all harvested at the end; grow bacteria til it’s in log phase then harvest entire batch (all in all out)
chemostat: medium is continuously added and continuously drained out; continuous harvesting; keeps it at one phase
99% organisms or culturable in the lab: T/F?
F
PHA/PHB can be produced using photosynthetic organisms, so in order to use photosynthetic organisms to produce PHB, what is absolutely required of the fermenter?
ample amounts of carbon and limiting amounts of other nutrients such as phosphorous
if plant can’t get DNA from Agrobacterium, how else can DNA be transplanted into the plant?
gene gun to insert the DNA thru the cell wall (biolistics)
niche and role of virus in the ocean
causes viral lysis of phytoplankton releasing nutrients for heterotrophic microbes below the water; they are an essential component of the microbial loop; mainly found in the photic zone where phytoplankton are also found
where does chemolithoautotroph in the deep subsurface get their carbon from?
hydrothermal vents which have underwater volcanic activity that releases minerals; they are the communities powered by geothermal energy; also found on hotter acidic springs
the dead zone of most eukaryotes result from:
microbes “bloom” and use up the available O2, quickly leading to the anoxic water states, which causes death of higher up eukaryotes
- phytoplankton proliferate and the heterotrophic microbes and zooplankton feed on the phytoplankton
- eutrification
in the surface zone/photic zone, primary production is what and thru what?
photosynthesis thru cyanobacteria
area of soil immediately surrounding plant roots:
rhizosphere
how to use hurdle technology to prevent food spoilage
use multiple levels of antimicrobial control in food as they work synergistically and give better overall protection
ex: milk pasteurization and cold storage
ketchup: high salt and low pH
salads: modified atmosphere packaging (MAP) and refrigeration
what is true of food fermentation? something about cheese production
- acids that LAB produce coagulate casein proteins found in milk
- the liquid can thicken for yogurt production
- the solids (curds) may separate from the liquid whey and form into large solid masses
- unripened loose cheese: curd is not separated from whey
- brie cheese: curd is cut and allowed to shrink; creamy and soft-ripened
- blue cheese and cheddar cheese: whey is drained, curd is cut and shrunk, ripening process further ferments it; hard ripened and aged
what is responsible for holes in swiss cheese?
CO2 production during fermentation from yeast
wastewater pre- treatment
physical removal of large objects thru straining
wastewater primary treatment
- physical removal of sediments and grease that form primary sludge
- skimmers remove the sludge
wastewater 2ndary treatment
uses trickling filter and activated sludge unit to form complex biofilms that break down organic compounds over time; using microbes to clean water
wastewater tertiary treatment
not always used
filtration or reverse osmosis is used to increase clarity of water and reduce metal content
disinfection in wastewater treatment
- quaternary treatment
- chlorination
- UV light exposure
- ozonation
example of emerging disease
ebola
morbidity rate
rate of disease in a population
- she changed it though to being described by incidence and prevalence
- incidence: number of new cases appearing in a population during a specific time period; may change with seasons or population immune status
- prevalence: total number of cases in a population at a particular time ; usually higher than incidence
mortality rate
rate of death by disease
epidemic
incidence of disease rises significantly above the normal expected value
- seasonal
- spatial
- common source
- propagated
ex: seasonal flu
outbreak
unexpected cluster of cases in a short time in a localized population; smaller than epidemic but could develop into an epidemic
ex: ebola
pandemic
global epidemic
ex: plague, small pox, AIDS, cholera, swine flu
lack of death from disease increases ___
prevalence rate
what determine the host range
pathogen’s ability to attach
measles transmitted from mom to 3 month baby
Horizontal transmission
Koch’s postulate limitations
- asymptomatic carriers
- not all people exhibit the same degree of infection or may not have any degree at all due to receptors
Koch’s postulates
- microbe is identified in every person with disease, but not those without illness
- pure culture of microbe is attained
- inoculation of microbe in healthy host causes illness
- microbe is recovered from inoculated host
Denaturing gradient gel electrophoresis (DGGE)
culture independent
separates DNA from environmental sample following fragmentation; can show big diff in DNA sequences without identifying each base; gradient is based on charge
Direct sequencing
culture independent
use PCR to read DNA fractions; use primers and sequence their 16S rRNA to identify cultures; each nucleotide is bound to a diff dye
enrichment culture
culture dependent
promotes growth of desired microbes over undesired cells
FISH
culture independent
labeled oligonucleotide probes to bind to specific DNA/RNA in a mixed population of cells
flow cytometry
culture independent
-detection of labeled cells in a mixed population by passing them thru a laser and detecting light emitted and sorted according to their chare
metagenomics
culture independent
-DNA from whole environment sample is used to construct genomic library; used to understand what community is made up of
winogradsky column
culture dependent; pond water in tube forms gradient from aerobic to anaerobic; different microbes flourish in diff areas of the column that correspond to diff nutritional microenvironments
bioaugmentation
adding specific degrading microbe to environment
ex: CP throwing oil eating bacteria into ocean
biostimulation
adding missing nutrient to promote microbe growth
cometabolism
addition of nutrient that stimulates broad substrate-range degradation pathway
chemolithoautotroph
responsible for primary production of organic compound; utilizes chemical and inorganic compounds as their electron and carbon source
OTU
organism share 97% of their ssu rRNA gene sequence
piezophile
capable of growth in high pressure
ex: deep sea levels
xenobiotics
chemical not found in nature and is difficult to degrade
how do bacteria get inside plant cell? spinach has been contaminated with E. coli; what can you do to better it?
bacteria can get into plant cells when their cell wall gets injured; thru insect bite; we can reduce them thru irradiation from UV rays, which only penetrates outer surface
indirect contact
getting sick by touching a lab coat or any other fomite
measles
aerosol
thru air or from someone coughing as bacteria travel from lungs to air
common cold
zoonotic
rabies; transmitted by animal
vertical disease transmission
HIV, toxoplasmosis, chickenpox
fecal oral
getting sick by bad hygiene
salmonella
how to transfer a plasmid to a specific target cell?
transformation
transduction
conjugation
2ndary metabolite
antibiotic
they are only produced during stationary phase because they aren’t necessary for growth of bacteria
if you want to keep the shape and taste of a strawberry, what would you do?
irradiate
