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Flashcards in 3: Microbial Growth II Deck (58):
1

Haemophilus Inflenzae

DOES NOT cause flu
Does cause:
- pneumonia, bacteremia (bacteria reproduces in blood: TSS), meningitis, otitis media (not fatal)

2

Haemophilus Inflenzae vaccine

protects against type B (Hib)... most virulent

works against the strucutre of the capsule

3

John's Hopkins sad story

head of the hospital made a vacciene... which didn't work

4

what is the fridge temp

4C

5

Why 4C?

highest density of water at this temperature

we want to keep things cold but not freeze. So we want water to be dense... if freezing happens it only happens on top

6

Are there bacteria that can spoil food at 4C?

YES! But not a ton. and growth is slow

but mostly fungus

7

Freezers:

-20C and thawing over night
thawing lets growth happen for half an hour, then refreezes

8

Why do humans die when we freeze them?

ice crystals... cells burst

9

Pasteurizatin

go above 60C: denaturation and of breakdown lipid membranes.
Go from medium zone to denaturation then quickly back down

10

The colorful pool

Each color is a different ecosystem of bacteria at a different temperature

11

Thermoaquaticus

TAC (for PCR)
useful in labs

12

Ocean vents

at the mid-Atlantic ridge where plates are moving apart.
no light... nrg taken from high energy of electrons coming out of vent

likely earliest life on earth

13

2 miles under the ice

liquid water that is bellow 0C.
lots of bateria

14

The main point...

if there is water, there can be life!

15

life needs one thing above all else

LIQUID WATER

16

pH requirements... most life

between 6.5 and 7.5
(in our bodies)

17

Why use high and low pH?

for long term storage
Prevention (not elimination) of growth

18

What is most affacted by changes in temperature and pH?

(DNA, RNA, or enzymes)

enzymes! Think proteins
the amino acid sequence doesn't change, just the organization

DNA and RNA are very stable

19

Can life survive in anhydrous places?

NO! theres no water, and life can't function without water

20

making pickles and sauerkraut

using bacterial acid production to preserve food

products of fermentation

done before refridgeration was a thing

21

Acidophiles

some live at pH of 4
chemoautrotrophs live at pH of 1
mud pools: very acidic soil. also near copper mines

22

Chemoautotrophs

use sulfer reduction to generate nrg
pH of 1

23

Osmotic Pressure

Salt to preserve food
inside cells salt conc: 1% or 1g/100ml
NaCl and KCl

24

plasmolyzed

when a cell is collapsed bc of lack of water inside (hypertonic solution)

25

if a cell is in hypertonic solution

it is NOT dead, just static/inert

26

what else can be used to make a hypertonic solution?

SUGAR

27

Does a spoonful of sugar help the medicine go down?

NO! it prevents the antibiotic from getting into bacteria

28

cheese

acids from bacteria make milk proteins curdle
addition of salt makes it resistant to microbial growth (does not inhibit fungal growth)

29

why cheese flavors are different?

its about culturing different types of bacteria in milk

30

creamy cheeses

due to fungus enzymes modifying proteins

31

Chemical requirements of bacterial life

Trace elements
organic compounds
carbon
Nitrogen, sulfer phosphorus
Oxygen

32

Trace elements

minerals: Fe, Cu, Mg, Mn
iron: cytochromes in ETC... life evolved in solution w/ lots of irron and copper: not so much now.

We have to put lots of nrg into keeping them around.
iron conc in body low: inhibits survival of many bact.

Get trace minerals from SEA SALT

33

Organic compounds

vitamins
we can't produce them: have to consume them to survive

34

oxygen:

is in water and disolveable in atmosphere
some don't need it the same way we do

35

Carbon

lots of different main types... some have genes to break down more tyepes than others...
USE THIS for pure cultures

36

Cellulose vs. Starch

animals can't break the bond of cellulse
- cows and termites have the right ecosystem to have beacteria that do. WE DO NOT

37

How do humans break down starch then?

amylase in mouth

38

Nitrogen

in the air... none of that is useable by humans
ability to break down nitrogen bond on earth in general is super rare
Needed by all life

39

Nitrogen cycle

bacteria in soil can deal with nitrogen: make gas useable
we have enzymes that can deal with some of the byproducts of oxidized or reduced nirgrogen.

40

Vovox...

the babies live in the mother
only mother can fix nitrogen

41

the secrete of dynamite

no oxygen required
mix high and low level nitrogen... BOOM

42

Sulfer

some amino acids need it:
Cysteine and methionine
Needed by all life

43

phosphorus

part of nucleic acid back boes
Needed in ATP
Needed by all life

44

Arsenate Experiment

aresinic is similar to phosphorus... can it replace it?
We need at least 1% phosphorus... but 99% can be replaced
functionally DNA could pretty much still reproduce without it
can't COMPLETELY replace it

45

5 groups of oxygen

Obligate Aerobes
Facultative anaerobes
Obligate anaerobes
Aerotolerant anaerobes
Microaerophiles

46

2 things to know about nitrogen

it is fixed by soil bacteria
nitrogen is required by all life

47

Obligate Aerobes

NO fermentation
REQUIRES oxygen to survive
can deal with ox radicals
grow on skin... all over body

48

Facultative anaerobes

uses oxygen to produce lts of nrg
CAN ferment. can survive w/o oxygen
can deal with ox radicals
us, lots of places of body... pretty much everywhere

49

Obligate anaerobes

ONLY grow in ABSENCE of oxygen... bc of radicals
cannot deal with ox radicals
grow in gut

50

Aerotolerant anaerobes

doesn't care about oxygen. DOESN'T use it, CAN live with it
CAN deal with oxygen radicals
grow all over body

51

Microaerophiles

requires LOW concs of oxygen
grows in lungs
CANNOT deal with radicals
grow in lungs, vaginal cavity, carries (cavities)

52

compare facultative anaerobes and aerotolerant

FA:
Aerotolerant:

53

PLEASE look at table on slide 24

PLEASE look at table on slide 24

54

how do we culture bacteria ... Pure culture

create situation where only the requirements of the organism of interest are met

55

non-selective media

undifined in character... lots grow but not all
rich: BHI, LB
blood agar, chocolate agar

56

selective media

only a few can grow
MAC with bile salts and selects for enteric bacteria (e. coli)

57

Broths

liquid media

58

Plates

semi-solid liquid