Lecture 7 - Genome Composition and Maintenance

Question 1

True or False. Microbes can only have circular or linear chromosomes

Answer 1

False. Most only have 1 type but Lyme disease has multiple copies of both

Question 2

What is the difference between genome and genes?

Answer 2

• Genome is the ALL the genetic information that codes for proteins
• Gene codes for a SINGLE protein

Question 3

What are two types of gene?

Answer 3

• Structural genes produce FUNCTIONAL DNA aka “proteins”

- DNA control sequences REGULATES the expression of structural genes aka “promotor/ regulatory proteins”

Question 4

What are some common methods that bacteria use to shrink their genome?

Answer 4

• Polymer dynamics: Idea that even without having space limited the chromosome would STILL fold
• Cellular Confinement: Crowding of the cytoplasm compacts the DNA into a single area
• Molecular Crowding: Similar to cellular confinement
• Supercoiling via topoisomerase: Tighten or loosen the DNA
  - Negative supercoiling ->Turning the DNA to the left uses NAP proteins to LOOSEN the DNA. Helps Helicase to rip apart the DNA/RNA strand
  - Positive supercoiling ->Turning the DNA to the right to TIGHTEN the DNA. Makes it harder to unzip the DNA strands