eating habits - 12th set Flashcards
Inoculum
the starting culture. term used when microbes are introduced into a medium
(i.e. rich nutrient source ) to initiate growth
Culture (newport)
growth of microorganism in a culture medium.
Growth (divide)
refers to microbial multiplication; increase in number (or population) i.e. bacterial division not bacterial size
Culture medium (lab only)
defined as nutrient material prepared for growth of microorganism in lab. bacteria growing in nature are not growing in culture medium. culture only in lab.
Pure culture (adopt)
descendants of a single cell and separated from others
Bacterial growth may result either in…(US)
a colony or a biofilm
Colony (kenny)
aggregation of cells arising from a single parent cell
Biofilm (bugs on water - malaria)
collection (many different species of microbes) of surface microbes living in a complex community. it amplifies disease causing ability of bacteria if they’re in a biofilm community
pure colony
when all cells are of the same type, no contamination.
Criteria for culture medium - it must contain (cooking)
appropriate nutrients in proper proportion for the specific microorganism
growth requirements - physical factors (PLOOT)
temperature, ph, light (energy source), osmosis and osmotic pressure
nutrient uptake - passive process (diffusion) (ex)
= downhill movement
- substance movement is from a region of high concentration to low concentration
- NO expenditure of cellular energy - simple diffusion, facilitated diffusion, osmosis
nutrient uptake - active process (group bacteria - desert - bus tour) it includes…
= uphill process - functions when bacteria are in low nutrient environment there is expenditure of cellular energy. includes
active transport and group translocation
Simple diffusion and ex. (think small)
- small or lipid soluble substances easily moves down concentration gradient across plasma membrane. - movement continues until equilibrium is reached between inside and outside. Ex: oxygen, co2, water, short chain/small fatty acids
Facilitated diffusion and ex. (GUV)
used by molecules unable to diffuse or fails to dissolve across lipid bilayer - use channel proteins Ex: glycerol, urea, vitamins
Difference between simple and facilitated diffusion? (shuttle - rainy day)
- carrier requirement,
- facilitated diffusion is a saturable process unlike simple. saturable process is when all binding sites are used up, it will come to a standstill. (shuttle) channel proteins are like revolving doors.
Active transport (front door - jonathan - buf)
involves substance movement from outside to inside, i.e. against concentration gradient (uphill) - substance that cross membrane is not altered. no chemical alteration of molecule
group translocation (group mail thieves)
cells picks substance even though they are in lower concentration outside than inside- substance altered during transport; prevents from leaving the cell.
group translocation process (group photo of pony)
glucose utilization by the phosphotransferase system, purines, pyrimidines and long chain fatty acids transport
Minimum growth temperature (no more)
lowest temperature at which species will grow; slow metabolism - any lower and it’s too slow to support metabolic activities of the cell.
Optimum growth temperature
species grows best at this temperature; fastest growth because all metabolic reactions are supported well at this temperature.
Maximum growth temperature (lowest and highest - body temp)
highest temperature at which growth is possible, though slow growth. beyond this temperature, cell dies. below 4 degrees C, bacteria cell will die. at 37 degrees about will grow best.
temperature has an impact on both (protein bar)
proteins and lipids.
proteins: high and low temps (H - kitchen table - H - freezer)
h2 and covalent bonds of proteins are broken. irreversible damage. low temp - h2 bonds are formed, and it disrupts the 3 dimensional shape of the protein.
lipids: high temps (melt/freeze)
lipids become too fluid, and it is not able to support membrane function. at low temps - the lipid becomes rigid and fragile.
Majority of human pathogens belongs to (japan)
…mesophile - based on temp requirements
Mesophiles (meso-moderate) (and temp in degrees)
moderate temperature loving microbes optimum temperature variable ( between 20 - 40 C) - optimum temperature for growth of most pathogen is close to that of host - human internal body temp
Thermoduric mesophiles (travel mug - cow)
can survive brief high temp during inadequate pasteurization and canning. these are non pathogenic.
Mycobacterium leprae (cool)
hansen’s disease (leprosy). lesions are at cooler areas of the body. face, extremities, toes and fingers, ears, etc. It is found in foot pads of armadillos because of lower internal body temp.
Treponema sps - syphillis (lesions - rabbit)
lesions are at cooler areas of the body, genitals, lips, throat, etc. earlier times, one treatment option was to induce malaria. treponema is cultivated in rabbit testicles.
Cells maintains constant internal…(dove - swiss)
pH close to neutral. energy harvesting reactions demands neutral ph.
Neutrophiles - preferred pH range (think neutral)
from 6.5 – 7.5; internal cell pH is neutral, Ex: majority of pathogenic bacteria belong to the neutrophils (6.5 - 7.5 ph) internal and external ph is always neutral.
Acidophiles ex and #
optimum pH below 5.5; preferred by many fungi (prefer high salt and sugar for growth)
Alkalinophiles (# and ex)
optimum pH above 8.5 (alkaline range) Ex: Vibrio cholerae - found in alkaline soils and lakes
Stomach (h.pylori - breaks down)
colonized by acid tolerant microbes helicobacter pylori - secretes urease. breaks down urea to CO2 and ammonia. ammonia forms neutral envir. surrounding bacteria.
Urogenital area of adult female (garden w/ out O)
colonized by fermenting microbes includes,
i. Normal microbiota and
ii. Abnormal microbiota aka bacterial vaginosis - dominated by Gardnerella vaginalis and other anaerobic bacterial sps
bacterial vaginosis is clinically associated (lacto)
Poor pregnancy outcome
PID - chronic inflammation
Postoperative wound infection
Endometrosis following elective abortion
Vaginal discharge as well as increased risk of HIV and STD’s
vaginal muscle cells used by lactose bacillus
normal microflora - Lactobacillus acidophilus (in a healthy urogenital system) forms….
lactic acid.
Low pH (acidic ph) of vaginal epithelium prevents..
other bacteria yet allows yeast to establish - a classical example of protection by our normal microflora for our body. on long term antibiotics, it kills these microbes, and opens door for yeast overgrowth.
Osmosis (passive transport)
net movement of solvent molecules across a selectively permeable membrane- movement is from area of high solvent to an area of low solvent concentration
Remember : Living system solvent is always….(balance water)
water. During osmosis, water movement is to the ‘drier’ side of membrane - difference in water concentration is required on each side of membrane
Osmotic pressure (solute)
pressure exerted on membrane by solutes in solution
staphylococcus aureus ( salt tolerant ) (and %) (leg)
can tolerate up to 20% salt cause pimples, sties, boils etc - life threatening toxic shock syndrome - bc it secretes super antigen
Water is a…
reactant in several chemical reactions - enzymes and nutrients are dissolved in water. Dehydrated structures ( like spores and cysts) and can be inhaled and they are resistant structures.
Mycobacterium sps (waxy)
cell wall retains water; enables cells to survive dry condition for extended time bc they have mycolic acid in the cell wall, it gives a waxy nature - so it doesn’t lose water.
Trace elements for growth (trace co-eskimo)
required in small amount, acts as cofactor (contributes to disease) for enzymes
Sterile tap water is preferred over
distilled water or deionized water, it contains sufficient amount of ions and satisfies nutrient requirement.
Nitrogen required for… (CB2 - vitamins)
NH2 group of amino acids, nitrogenous bases of the nucleic acid contains the amine group
Phosphorous (kin - chyrno)
needed for proteins, nucleic acids (as phosphate backbone), phospholipids, ATP synthesis
Sulfur - chemical factors (sailor - cyst - di)
for synthesis of sulfur containing amino acids ( binds via S-S binds); includes cysteine, methiaonine. can make disulfide bonds. as well as for some vitamins ( like thiamine and biotin)
Other elements: such as Ca, Mg…(CMM FFLT the iron)
Mn, Fe, transferrin, ferritin and lactoferrin - They are all iron binding proteins. they limit the iron availability.
Growth factors ( aka organic growth factor) (anorex - corner)
are low molecular weight organic compounds that must be supplemented in medium since bacteria can’t make it; they are in addition to C and energy sources.
what are Transferrin and ferritin? (simple)
the iron binding proteins in humans.
Lactoferrin (drinking milk)
extremely high affinity for iron (II) present in saliva, mucus and milk. excess iron causes more bacterial infections. we only have limited storage for iron.
Siderophores (side of stomach)
bacterial secreted iron binding protein. it includes enterobacin.
siderophore complex - 2 fates (iron - on or off)
can enter as such, binds to receptor on cell surface, brought inside - iron stripped off. OR iron is made free first, subsequently enters cell by transport protein
most pathogens belong to the….(chemo - berkeley bowl)
chemoheterotrophs. most important one. they use carbon and energy source from breakdown of organic compounds
energy source used for (baby - BTM)
- building blocks
- transport processes
- motility
energy sources (2) (beach - sunlight) ALS
1) sunlight - uses radiant energy
2) Metabolism of chemical compounds - amino acids, lipids, or sugar
sunlight (camera)
Phototrophs - (photo - light, trophs - nourishment)
