Lecture Exam 2 reduced set

2 groups of macronutrients? what do they do?

1. C,O,H,N,S,P

   1.   lipids, sugars, proteins, nucleic acids

2. K+, Ca2+, Mg2+, Na+

   1. stabilize enzymes and ribosomes

   2. long range electrical signaling w/in biofilms

2 groups of micronutrients

1. inorganic- trace metals, co factors for enzymes - Fe, Se, Mn, Zn, Co, Mo, Ni, Cu

2. organic - growth factors- amino acids, purines, pyrimidines, vitamins

what is a cofactor? what if cofactor missing?

1. micronutrient needed for enzyme function.

2. Enzyme can be made without it but wont function correctly w/o it

2 types energy sources. 2 types of electron sources. 2 types of carbon sources. how many metabolism types total?

1. Energy

   1. photo

   2. chemo

2. Electron

   1. litho

   2. organo

3. Carbon

   1. autotroph = CO2

   2. heterotroph = organic molecules

4. 8 different types

what kind of metabolism for:

1. cyanobacteria

2. nonsulfur bacteria

3. methanogens

4. sulfur-oxidizing bacteria

5. most nonphotosynthetic microbes

1. photolithoautotroph

2. photoorganoheterotroph

3. chemolithoautotroph

4. chemolithoheterotroph

5. chemoorganoheterotroph

what type and flavor is Columbia (CNA) agar? For what and why?

1. complex

2. selective for G+

   1. CNA (Columbia nalidixic acid) inhibits G-

3. Differential- inclusion of 5% sheep’s blood shows hemolysis

3 (4) types of active transport? which one involves chemically modifying the substance being transported?

1. simple transport - symport and antiport

2. ABC transport

3. Group translocation (chemical modification)

Two types of simple transport? What are they? What is the energy source? example of a symporter? what protein(s) are involved

1. symport- where a solute and a proton are co-transported in the same direction

   1. lac permease- uptake of lactose

2. antiport- where a solute and a proton are transported in opposite directions

3. H+ motive force

4. 1 transmembrane transport protein

1. sodium-proton: antiporter or symporter? what is it transporting?

2. lac permease: antiporter or symporter? what is it transporting?

3. glucose: 2 ways?

1. antiport, pumping out sodium

2. symport, pumping in lactose

3. facilitated diffusion via permease, or active group transport where it’s phosphorylated to glucose-6-phosphate

3 ways group translocation (phosphotransferase system) is different from other the 2 active transports?

1. Transported substance is chemically modified (phosphorylated) during transport process

2. energy rich organic compound called PEP (phophoenolpyruvate) drives the transport instead of proton motive force or ATP

3. many different proteins (enzymes) involved in the process

ABC transport: 3 components? 2 steps? what does ABC stand for?

1a. substrate binding protein,

1b transmembrane transporter,

1c ATP-hydrolyzing protein

2a substrate binding protein binds substrate

2b binding protein interacts 2/ transmembrane component to transport via ATP

3. ATP-binding cassette

2 reasons agar is a good media? what temps does it melt and solidify

1. most microbes can’t digest it

2. it’s melting temp is much higher than its solidifying temp, so it remains solid at room temp

3. melt at 90F, harden at 40

4 stages of microbe growth curve. what happens at each?

1. lag: adjusting to new medium. synthesizing enzyme and cofactors for new environment

2. exponential (log) : doubling at regular intervals, balanced growth (cell components made at constant rates)

3. stationary : growth = death, nutrient limitation

4. decline-:cell death, “viable not culturable”= stress response, returns to norm if conditions improved

Growth equation and variables

N_n = N0 ×2ⁿ

N_n = cell # after n generations

N0 = initial cell #

n= # of generations

1. what is generation time (g)?

2. what is growth rate (k)?

3. what is n?

4. what is its relationships to k: k = x = x? g = x = x?

5. population takes 6h to double once, what’s generation time?

6. relationship b/t N_n and N₀ ?

1. time per generation t/n, or “time to double”

2. # of generations per unit of time (n/t)

3. n = # of generations

4a. k = n/t = 1/g

4b. g = t/n = 1/k

5. g = 6/1

6.  Larger difference b/t N_t and N₀ = higher n

cell concentration equation for viable count (dilute and plate)? what does N represent? when can you stop diluting?

concentration (cells/mL)= N (dilution factor) / mL plated

N = CFU (how many colonies are counted on the plate)

want total CFU to be between 25-250 cells for statistical relevance

Chlamydomonas nivalis: what kind of temp, what is it?

1. psychrophile

2. red snow algae from carotenoids

3 kinds of organisms concerning external acidity? example organism for acidophile and alkaliphile? what pH must all cells keep internally and why?

1. acidophile- less that pH 5

   1.      picrophilus- most acidophilic

2. neutrophile- pH 5.5-8

3. alkaliphile- 8+

   1.     Bacillus Firmus

4. 5-9

ideal cardinal temps for the 5 temp categories? max for methanopyrus?

1. psychro= 0-20, 15C optimum

2. psychrotolerant= 0-40 20-40C optimum

3. mesophile= 8-48C, 20-40C optimum

4. thermophile = 45-80C, 55-65C optimum

5. hyperthermophile= 55-?C, 80-?C

6. methanopyrus 122C max

What kind of organism is Thermus aquaticus? What is it used for industrially and why?

1. hyperthermophile

2. its DNA polymerase is used to automate repetitive steps of PCR

3. hyperthermophile enzymes are generally more stable than mesophiles

1. what is water activity?

2. 2 factors that impact water activity?

3. water activity equation and what is the range of values?

1. water availability

2. water quantity - how dry or wet the environment is

3. solute concentration- how much salt, sugar, other is dissolved in the environment’s water

4. a_w = (vapor pressure of solution) / (vapor pressure water)

5. Values of a_w vary between 0 (no free water) and 1 (pure water)

what they like?:

osmophile

xerophile

halotolerant

halophile

extreme halophile

what is staph aureus and halobacterium salinarum?

1. Osmophile- live in high solute concentrations

2. Xerophile- live in dry environments

3. Halotolerant- tolerate salt but grow best w/o

4. Halophile- salt lover (0-12%) - need it

5. Extreme halophile (15-30%)

6. S. aureus = halotolerant

7. halobacterium salinarum = extreme halophile

aerobe

facultative anaerobe

microaerophile

anaerobe

aerotolerant

what oxygen levels do they prefer in their environments? where grow?

1. obligate Aerobe- can respire O2, requires O2 at atmospheric conditions)

   1. only in oxic zone

2. facultative anaerobe- grow best in oxygen but not required

   1. best in oxic zone, throughout the tube

3. microaerophile- require O2 but at lower than atmospheric levels (microoxic conditions)

   1. just below the oxic zone, some in oxic zone

4. obligate Anaerobe- cannot respire O2, strict and won’t grow in its presence)

   1. only towards bottom of tube

5. aerotolerant- will grow in its presence,  growth equal w/ or w/o

   1. equal levels of growth throughout a tube

regarding oxygen tolerance, what kind of organisms are methanogens and clostridium?

1. obligate anaerobes

2. aerotolerant

antiseptic v. chemotherapy v. antimicrobial

1. antiseptic = chemical that kills microbes ON LIVING TISSUE to prevent infection

2. chemotherapy = chemicals that kill microbes WITHIN LIVING TISSUE

3. antimicrobial = agents that are cidal (kill) or static (prevent growth)

what is decimal reduction time (D)? what percentage loss? how does population size affect it?

1.    time required to achieve a 1-log (1 order of magnitude) reduction in the survival fraction (100% down to 10%) when heating at a steady temp

2.       population has been reduced by 90%,

3.    this value is Independent of starting cell #

what is thermal death time? how does population size affect it?

1. time it takes to kill all organisms at a given heat

2. more cells = longer to kill

4 low-resistance-to-chemical pathogens and 2 high resistance ?

1. yeast, protozoa, vegetative gram+, enveloped viruses

2. endospores, prions (isolates from bacteria)

5 intermediately resistant-to-chemicals pathogens?

cysts/oocysts

mycobacteria

non-enveloped viruses

filamentous fungi

veg gram-

what type of microbes are resistant to freezing, 2 food spoilage organisms?

1. psychrophiles

2. Camplybacter jejuni- chicken, has become resistant.

3. Listeria monocytogenes

who invented pasteurization and for what? what is the process? what is the purpose of it? what is the indicator that it has succeeded?

1. louis pasteur for wine spoilage fermenters

2. briefly heat to 60C

3. kills pathogens and fermenters

4. alkaline phosphatase test- naturally in milk, if not present, heat was high enough

what microbe is resistant to triclosan?

Psuedomonas aeruginosa

who invented the chemical control phenol and for what? what is the mechanism of action?

1. Joseph Lister- used carbolic acid during surgery to sterilize instruments and hands

2. denatures proteins, disrupts membranes

mechanism of halogens on microbes? 2 examples? what are they used for?

1. oxidize cell components

2. chlorine (bleach) - kills everything EXCEPT spores

3. iodine- pre surgery

heavy metal chemicals (silver, mercury, arsenic,zinc, copper): -cidal? mechanism of action? which are still used? how do the current ones work?

1. bacteriostatic, + ions disrupt CW, respiration, and DNA

2. silver nitrate and silver sulfadiazine

   1. make microbe produce Reactive Oxygen Species (ROS)

Reactive Oxygen Species (ROS): where do they come from? mechanism of action?

1. chemicals containing heavy metals silver nitrate or silver sulfadiazine induce microbes to make ROS like peroxide internally

2. oxidative damage to proteins, DNA, and lipids

what kind of chemical is a Quaternary Ammonium Compound (QAC)? Structure? mechanism of action on microbes? why are they preferred? what is amphipathic mean?

1. cationic detergent

2. + charged head = quaternary nitrogen group

3. disrupts membranes

4. stable and nontoxic compared to other detergents

5. hydrophilic + head, hydrophobic tail

aldehydes: what kind of agent/mechanism of action? what used on?

1. alkylating agent →crosslinking proteins and nucleic acids, disrupts metabolism and reproduction

2. special bc its sporicidal, but also kills bacteria, fungi, spores/endospores, and viruses

ethylene oxide: what kind of agent is it and mechanism of action? what does it kill? what 2 things is it used to sterilize?

1. alkylating agent → disrupts cell metabolism and reproduction

2. microbicidal, sporicidal

3. packaged items and heat sensitive material

COE2-2hexyl: what is it? mech of action? why special?

1. broad spectrum synthetic antimicrobials (chemotherapeutic agents)

2. breaks down bacterial CM

3. idoesn’t lead to resistance

when does staph aureus pneumonia happen

tends to follow viral infections, bacteria already on the body

staph aureus food poisoning: cause, how fast?

1. intoxication from exotoxin aureus secretes, not infection

2. fast 2-6 hours

scalded skin syndrome: what cause what is it?

staph aureus exotoxin causes baby skin to peel

toxic shock syndrome: whhat is it and what cause?

staph aureus secretes more exotoxin TSST-1 in anaerobic conditions when using absorbent tampons

MRSA: what cause, what type of infection

1. methicillin resistant staph aureus

2. nosocomial infection (acquired in hospital)

pseudomembraneous enterocolitis: what is it what causes it?

1. staph aureus overgrowth in bowels

2. prolonged antibiotic therapy cuts down normal intestine flora

folliculitis: what is it what causes it?

1. small red bumps develop localized to hair follicles

2. staph aureus

furuncle: what is it what causes it?

1. a boil, hair follicle infection also involving surrounding tissue, penetrates into subcutaneous

2. staph aureus

carbuncle: what is it what causes it?

1. cluster of boils, penetrates deeper to subcutaneous fat

2. staph aureus

3 general traits that make staph aureus more pathogenic. why unique among staph?

1. has capsule,

2. thick CW,

3. has enzymes/toxins

4. only clinically significant staph that is coagulase +

capsule: what does it do and how?

a). protects from immune system → pathogenicity

b). prevents from being engulfed by WBCs which enables bacteria to attach to surfaces

Protein A: what is it who has it?

1. binds antibodies to keep WBCs from recognizing and phaging

2. staph aureus

hyaluronidase: what is it who has it?

1. enzyme breaks down hyaluronic acid which binds connective fibers, allows staph aureus and strep a to spread into other parts of the tissues

DNase: what is it who has it

1. enzyme breaks down DNA, especially in NETs (neutrophil extracellular traps). (disrupts immune system

2. staph aureus

Neutrophil extracellular traps (NETs): what can destroy it?

1. nets made of DNA released by neutrophils (immune cells) to capture and kill pathogens

2. staph aureus

lipase: what is it who has it?

1. enzyme breaks down lipids in the skin, nutrients released, makes room for staph aureus growth

beta-lactamase: what is it who has it?

1. enzyme breaks down penicillins

2. staph aureus (penicillin resistant)

exfoliatins: what is it who has it

1. exotoxin causes skin sloughing

2. staph aureus

leukocidins: what is it who has it?

1. kills WBCs

2. staph aureus

superantigens: what is it, what 2 things does it do, who has it? 2 examples?

1. exotoxin that causes large scale t-cell activation:

2. prevent targeted immune response, can cause toxic shock

3. TSST-1 and enterotoxins

TSST-1: what 2 things is it, who makes it?

1. exotoxin and superantigen, causes toxic shock

2. staph aureus

enterotoxins: what is it, what do they cause, who makes it?

1. exotoxins that act in gut

2. staph food poisoning, enterocolitis

3. staph aureus

what reaction does coagulase perform?

converts fibrinogen to fibrin

strep throat: what is it what causes it?

1. (Group A) strep pyogenes

tonsilitis: what is it what causes it?

1. sudden severe sore throat, fever, and swollen tonsils with white patches.

2. (group A) strep pyogenes

Erysipelas: what is it what causes it?

1. contagious skin infection of the upper dermis and lymphatic vessels

2. (group A) strep pyogenes

impetigo: what is it what causes it?

1. skin infection causes red sores mainly children; extremities, nose and mouth

2. (group A) strep pyogenes

septicemia: what is it what causes it?

1. extreme response to an infection

2. group a strep and strep pneumoniae

strep deadly pneumonia: what is it what causes it?

1. rare, after viral infections, often fatal

2. (group A) strep pyogenes

necrotizing faciitis: what is it what causes it?

1. infection that destroys fat muscle and skin tissue

2. group A strep (strep pyogenes)

6 enzymes/toxins that make strep pyogenes (group A) pathogenic?

1. streptolysin S

2. streptolysin O

3. erythrogenic toxin

4. streptokinase/fibronolysin

5. hyaluronidase

6. exotoxins

2 strep pyogenes (group A) hemolysins: oxygen stability, aerobic v anaerobic conditions?

1. Streptolysin O (not normally seen) = oxygen labile, only makes hemolysin if anaerobic

2. Streptolysin S = oxygen stable, b hemolysis under both aerobic and anaerobic conditions

3. both are b hemolytic when active

streptolysin S: what is it who makes it what conditions?

1. Streptolysin S = oxygen stable, hemolysis under both aerobic and anaerobic conditions

2. Group A strep (pyogenes)

streptolysin O: what is it who makes it what conditions?

1. oxygen labile hemolysins made only under anaerobic conditions

2. Group A strep (pyogenes)

erythrogenic toxin: what is it what makes it?

1. toxin that causes rash of scarlet fever

2. (group A strep) strep pyogenes

scarlet fever: what is it what causes it

1. scarlet rash and white strawberry tongue

2. group A strep (strep pyogenes)

streptokinase/fibrinolysin: what is it what makes it?

1. breaks down fibers to help spread

2. strep pyogenes (group A)

hyaluronidase: what is it what makes it?

1. breaks down hyaluronic acid that connects fibers, helps spread

2. strep pyogenes (group A)

1. bacitracin disk test: what is positive, what’s it testing for

1. bacitracin disk on plate, no growth around if susceptible (+)

2. differentiates strep pyogenes bc group A is sensitive to bacitracin

2 post-streptococcal diseases? what causes?

1. rheumatic fever and glomerulonephritis

2. group A strep (strep pyogenes)

rheumatic fever and glomerulonephritis: what type of disease and what causes them? mech of action?

1. post-streptococcal diseases

2. group A strep (strep pyogenes)

3. group A has antigen resembles heart valve and kidney, causing antibodies to cross react w/ heart and glomerulus (kidney)

necrotizing fasciitis: what is it what causes it?

1. infection destroys fat skin and muscle

2. group a strep (strep pyogenes)

CAMP test: what is it differentiating? how? what does a + result look like and what does it indicate?

1. used to identify Group B beta strep based on their formation of CAMP, which enlarges B-hemolysis

2. the microbe being tested streaked at right angle to staph aureus

3. a CAMP (+) result will look like an enlarged section/arrowhead of B-hemolysis where the 2 streaks meet

meningitis: what is it what causes it?

1. infection of brain and spinal cord

2. Group B b-hemolytic strep

2 drugs enterococcus can be resistant to? how to treat enterococcus diseases? what range of temps?

1. all low susceptibility to penicillin

2. vancomycin, sometimes (VREs)

3. susceptible to aminoglycosides

4. grow in wide range of temps

Bile esculin Test: purpose? how does it work? what does a positive result look like?

1. separate enterococcus/group d from other groups

2. Enterococcus hydrolyze esculin to products that react w/ ferric citrate in the agar → produces black iron salts

3. positive result turns media from yellow to black = Enterococcus or Group D

Strep pneumoniae: morphology, location, metabolism need, lysis

1. G+ diplococci, lancet-shaped (elongated)

2. normally oropharyngeal flora

3. needs increased CO2

7 diseases of streptococcus penumoniae

– a). Most common cause of community acquired

pneumonia

– b). Meningitis

– c). Septicemia

– d). Pericarditis

– e). Pleuritis

– f). Otitis media

– g). sinusitis

strep pneumoniae: catalase, lysis, optochin/p-disc, bile salts, other?

1. -

2. alpha hemolysis

3. optochin/p-disc test sensitive (+)

4. lysed by bile salts

5. serological tests

viridans strep: location, pathogenicity

1. normal flora same as others skin mouth

2. not normally pathogenic

Outline staph identification

1. do a coagulase test

   1. coagulase(+) = staph aureus or staph intermedius

      1. do a VP test

         1. aureus = VP (+), intermedius = VP(-)

   2. coagulase(-) = staph epidermidis or staph saprophyticus

      1. do a novobiocin disk

         1. epidermidis is susceptible (+)

         2. saprophyticus is resistant (-)

alpha-hemolytic strep identification pathway:

1. If observe a-hemolysis on blood agar

2.optochin disk test
a. sensitive = strep pneumoniae
b. resistant = viridans strep = strep mutans

beta-hemolytic strep identification pathway:

1. If observe a-hemolysis on blood agar

2. CAMP Test

   1. CAMP + = Group B Strep - strep agalactiae

3. Bacitracin test

   1. sensitive = Group A = strep pyogenes

pathway for gamma hemolytic strep identification

1. bile esculin test + 6.5% salt test on gamma hemolytic growth
   b. resistant bile salt, sensitive 6.5% salt = Group D strep (bovis, equis)
   c. resistant for both = Enterococcus

2. vancomycin test on Enterococcus
   a. resistant = VRE

cidal static or cytic and against what gram)

1. aminoglycosides

2. tetracyclines

3. macrolides

4. quinolones

5. all antimetabolites

6. daptomycin

7. polymixin-b

1. cidal (G-)

2. static, broad spectrum + or -

3. broad spectrum

4. cidal croad spectrum + or -

5. static broad spectum + or -

6. cidal (G+)

7. G-

Paul Ehrlich is known for what 3 things? why were they important?

1. trypan red - 1st synthetic chemical compound that could cure infections in living animals

2. arsphenamine (Compound 606) - replaced dangerous mercury as treatment for syphilis

3. the term “magic bullet”- selectively targeting of pathogens

trypan red: who made it/when? what did it do? why important?

1. paul ehrlich (1904)

2. killed trypanosomes

3. 1st synthetic chemical compound that could cure infections in living animals

arsphenamine (compound 606): who made it/when? what did it do?

1. Paul ehrlich 1910

2. arsenic compound treats syphilis

what is Gerhard Domagk known for? why important?

1. Prontosil (1932) - treats Strep and Staph

2. 1st sulfa drug

Prontosil: who made it/when, what is it for/ what does it do, why important?

1. Gerhard Domagk (1930)

2. treats Strep, Staph bc its metabolized into sulfanilamide

3. 1st sulfa drug