Bacterial Genetics (Palmer)

Question 1

What is the variability of genome sizes in bacteria?

Answer 1

Small: Chlamydia (1.0 Mb), Pneumoniae (600Kb)

Large: E. Coli (5.5Mb)

Question 2

What are the three phases of bacterial growth?

Answer 2

1. Lag Phase: adapt to environment - begin metabolism
2. Exponential (log) phase: bacteria grow at a high rate
3. Stationary phase: growth stops (nutrient exhaustion or toxic by-products)

Question 3

What does the growth curve of a typical bacteria look like?

Answer 3

S

Question 4

What is a typical characteristic of a bacteria with a large genome?

Answer 4

More diversity, can survive in more areas

Question 5

What is a typical characteristic of a bacteria with a small genome?

Answer 5

Often parasitic (cannot survive outside of hosts) and have a narrow niche

Question 6

What are some ways bacteria transfer genetic information?

Answer 6

1. Natural transformation: take up DNA from the environment
2. Conjugation: transfer of DNA via sex pili
3. Transduction: transfer of DNA by a phage
4. Transponons: DNA inserts/excises itself

Question 7

How do bacteria regulate their genes?

Answer 7

1. Transcriptional: promoter
2. Post-transcription: mRNA levels
3. Translational: initiation
4. Post-translation: protein turnover

Question 8

What are some methods for determining gene functions?

Answer 8

1. Random mutagenesis: random mutations with library
2. Allelic replacement: gene replaced with marker
3. Complementation

Question 9

How do researchers screen for virulence factors?

Answer 9

Negative selection: select mutants unable to grow under certain conditions

Positive selection: only bacteria with the ability to invade are selected

Question 10

What is RNA-seq?

Answer 10

Method for testing genetic mutations.

Grow two different cultures -> make cDNA ->prep and sequence libraries for changes