MICRO BIO 304 exam 1 terms

Escherichia coli characteristics

bacteria

enteric

gram negative

rod

motile

Pseudomonas fluorescence characteristics

bacteria

pseudomonas

gram negative

rod

motile

produces yellow green fluorescent pigment

Saccharomyces cerevisiae characteristics

Eukaryote

Yeast

ferments sugars to ethanol and CO2

round/oval cells

Staphylococcus epidermidis characteristics

bacteria

halophile

gram-positive

cocci, grape like clusters

Serratia marcescens characteristics

bacteria

enteric / chromogenic

gram-negative

Rod

motile

produces red pigment

Bacillus cereus characteristics

bacteria

endospore (oval) former

gram-positive

large rods

survive in high heat

Streptomyces characteristics

bacteria

actinomycete

gram-positive

filamentous, branching hyphae

Chalky white colonies

Chlorella characteristics

Eukaryote

Algae

Round green cells

Light is required for growth

Geobacillus characteristics

bacteria

endospore former

gram positive

rod

motile

What was the endospore former isolated in unit 6?

bacillus or geobacillus

What was the yeast isolated in unit 6?

Saccaromyces

What was the enteric isolated in unit 6

Escherichia

What was the halophile isolated in unit 6?

Staphylococcus

What was the chromogenic isolated in unit 6?

Serratia

What was the algae isolated in unit 6?

Chlorella

Primary source

original report of research by the people who did the work

Secondary source

source that analyzes, summarizes, or interprets primary research done by others

Tertiary source

source that complies or condenses primary and secondary sources into one review

Positive control

a treatment that should produce measurable results

Negative control

a treatment that should have no measurable results

Random error

unpredictable difference between measurements

Systematic error

consistent error that shifts all results in the same direction

Human/procedural error

mistakes made while preforming procedure

Biological error

natural difference between living samples

Range of p1000

1000  µL to 100 µL

Range of p200

200 µL to 20 µL

Range of p20

20 µL to 2 µL

What does OD600 measure

turbidity

What does spectrophotometer measure

absorbance

What are common carbon sources

glucose, other sugars, extracts

What are common nitrogen sources

ammonium, sulfate, peptone, extracts

What are common phosphorus sources

potassium phosphate, extracts

What are common salt sources

NaCl, bile salts, potassium phosphate, extracts

What are common trace metal sources

magnesium sulfate, water

What are common buffer sources

potassium phosphate

What are common vitamin sources

synthetic vitamin mixture, extracts

What are common amino acid sources

peptone, casein hydrolysate, extracts

What are common pH indicators

neutral-red, brom-thymol blue, brilliant green, brom-cresol purple, methyl red

Defined medium

medium where exact chemical composition is known

Complex medium

medium where components or exact amounts are unknown

Selective medium

media that favors the growth of certain organisms and inhibits others

Differential medium

medium that allows you to distinguish between organism by visual differences (don’t inhibit growth)

Aerobes

can only survive in high O2 enviromentsA

Anaerobes

Can only survive in no O2 environments

Aerotolerant anaerobes

grow the same in any amount of O2 by always fermenting

Facultative anaerobes

prefer O2 but don’t need it to survive

Microaerophiles

can only survive in specific low O2 environments

MacConkey properties

selective and differential

has bile salts and crystal violet (inhibits gram pos)

has lactose and pH indicatorM

MacConkey uses

only grows gram negative bacteria

red colonies show lactose fermentation

colorless colonies show non-lactose fermentation

Used to isolate enterics

AIA properties

selective

Casein/asparagine = nitrogen source

Glycerol = carbon source (only actino can use)

Sodium propionate = inhibit fungi and many bacteria

AIA uses

isolates actinomycetes

Mannitol Salt Agar properties

selective and differential

NaCl selects for halophiles

Mannitol + pH indicator differentiate mannitol fermenters

Mannitol Salt Agar uses

isolate halophiles

yellow colonies show mannitol fermentation

pink/red medium shows no mannitol fermentation

Sabouraud-Dextrose Agar (SDA) properties

Selective

high dextrose and low pH selects for fungi

SDA uses

isolate mold or yeasts

wasn’t used in lab

MALT agar properties

selective

Acidic environment (fungi)

often paired with an antibiotic (no bacteria)

MALT agar uses

isolate yeast and mold

smooth = yeast

fuzzy = mold

EE broth properties

selective and differential

ox bile and brilliant green inhibit

dextrose + pH indicator shows fermentation

EE broth purpose

select and enrich for enterics (gram negative) before plating

yellow broth → ferments dextrose

purple broth → no fermentation

FW media properties

selective (mildly)

paired with incubating under light

FW media uses

isolate algae

green growth on bottom → algae

Steps for isolating endospore formers

dilute sample

heat shock

serial dilute sample

plate on YTGA and restreak (YTGA) until pure

Steps for isolating fungi

Add antibiotic to MALT plate

plate sample and restreak (MALT) until pure

Steps for isolating actinomycetes

plate sample on AIA

restreak on (YTGA or AIA) once pure

Steps for isolating enterics

inoculate EE broth with sample

streak sample on MAC plate

Use purple/red colonies

Restreak (YTGA or MAC) once pure

Steps for isolating halophiles

Inoculate YTG + salt broth with sample

Restreak on MSA plate

Restreak (YTGA or MSA) once pure

Steps for isolating chromogenic

streak plate on YTGA

Choose colorful colonies

Restreak (YTGA) until pure

Steps for isolating algae

pipette sample into FW medium

grow under light @ room temp

Take green growth from bottom and transfer to new FW medium

Repeat until pure

Lactose fermentation test

Steps: inoculate tube and incubate, check for turbidity

purple to yellow: positive for lactose fermentation

Bubble in durham tube: gas production with fermentation

Catalase test

Steps: prepare smear of fresh cells on slide and drop H2O2 on slide

If bubbles produced: catalase positive

Starch hydrolysis test

Steps: streak a starch agar plate and incubate, flood with iodine

if halo around cells: secreted amylase and positive for starch break down

Nitrate reduction test

Steps: inoculate broth and incubate, add reagent A+B, add zinc

if bubbles in durham tube → denitrification

if turn pink after A+B → positive for nitrate reduction

if turns pink after zinc → negative for nitrate reduction

Motility test

steps: stab a needle with cells straight into motility medium

if growth spreads away from stab line → motile

MAC agar plate test

steps: streak cells on MAC plate

pink growth → gram negative lactose fermenters

colorless growth → gram negative non lactose fermenters

no growth → gram positive

MALT agar plate test

Steps: streak a MALT plate with cells

growth → fungi (yeast or mold)

What enzyme is a positive lactose fermenter making

B-galactosidase (splits lactose into glucose and galactose)

What enzyme is a positive catalase test making

catalase (breaks down toxic byproducts)

What enzyme is a positive starch hydrolysis test making

a-amylase (breaks down polysaccharides)

What enzyme is a positive nitrate reduction test making

nitrate reductase (final e- acceptor is NO3- not O2)

Size of bacteria

0.5-5 µm

Size of eukaryotic cells

10-100 µm

Cocci

spherical shape

Bachili

rod shape

What sugars does yeast ferment

glucose, sucrose, maltose (not lactose)W

What type of robe is yeast

Facultative anaerobe (only ferments when O2 not present)