Bacterial Metabolism and Genetics Flashcards Preview

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Flashcards in Bacterial Metabolism and Genetics Deck (54)
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1

Nutrients required by bacteria

CHONPS and trace metal salts

2

What versions of C and N are most important?

Reduced Form

3

Describe the shape of a bacterial growth curve based on temperature.

The curve leans with the highest point/optimum at higher temperatures

4

What is the significance of the bacterial growth curve?

Increase in temperature by as little as 2 degrees causes a large drop in population -- FEVER

5

Three types of bacteria based on pH? Who is most common in the stomach? The body?

Acidophile, Neutralophile, Alkalophile
Acidophile
Neutralophile

6

Circumstances in which an aerobe will grow?

O2
Needs an electron acceptor -- O,N,S

7

Circumstances in which an anaerobe will grow?

Grows in No O2
O2 forms radicals

8

Circumstances in which facultative anaerobes grow?

Grows in O2, less well without O2
Have TCA and can ferm.

9

Circumstances in which aerotolerant will grow?

Will grow with or without O2
Doesn't use O2 anyway

10

Circumstances in which microaerophile will grow?

Grows in O2 below 0.2 ATM
Needs O2, but too much makes radicals

11

Oxygen sensitivity of more tissue?

Anerobic

12

Oxygen sensitivity of lungs?

Aerobic

13

Oxygen sensitivity of tonsils/back of throat?

Microaerophile

14

Four phases of bacterial growth cycle?

Lag, Exponential, Stationary, Decline

15

What stage are bacteria typically in the lab? In the body?

Exponential Phase.
Stationary Phase.

16

What occurs during the lag phase?

Adaption to new nutrients
New enzyme synthesis/up-regulation

17

What occurs in the exponential phase?

Growth and binary division

18

What occurs in the stationary phase?

Crowding, Starvation or Toxic Conditions
Stress Genes Upregulated

19

What occurs in the decline phase?

Cells begin to lyse.

20

What occurs in bacterial latency?

No division, allows for hiding from immune response
"Persister cell"

21

How do persister cells come about?

Turn off metabolism
Turn on dormancy pathways
No growing/dividing

22

Role of persister cells in treatment?

Treating against persister cells leads to more rapid cure

23

Describe the bacterial chromosome.

Circular
Stable w/out telomeres
Haploid (typically)
Associated with proteins (structural and regulatory)

24

What are merodiploids?

Genes in multicopy in the bacterial chromosome

25

Describe a plasmid?

Circular, smaller than chromosome
Can exist in hundreds of copies per cell

26

What controls plasmid replication?

Cop proteins

27

In a broad sense, how does bacterial transcriptional regulation occur?

Negative Regulation -- Protein Repressors
Positive Regulation -- Protein Activators

28

Where do repressors bind?

Between promoter and gene

29

Where do activators bind?

Upstream of promoters

30

How do environmental signals modify gene regulation?

Small molecules alter the shape/bind to regulatory proteins