TLS Online TPP Program

#Id: 3171

#Unit 3. Fundamental Processes

The E. coli enzyme acts by antagonizing the replication helicase in a direction a) manner by direct contact between the DnaB helicase and Tus.

TLS Online TPP Program

#Id: 3172

#Unit 3. Fundamental Processes

Deletion of the ter sites does not, however, prevent normal replication cycles from occurring, although it does affect segregation of the daughter chromosomes.

TLS Online TPP Program

#Id: 3173

#Unit 3. Fundamental Processes

The two replication forks meet and halt in a region approximately halfway around the chromosome from the origin.

TLS Online TPP Program

#Id: 3174

#Unit 3. Fundamental Processes

 In E. coli, two clusters of five ter sites each, including terk, -I, -E, -D, and -A on one side and terC, -B, -F, -G, and -H on the other, are located -100 kb on either side of this termination region.

TLS Online TPP Program

#Id: 3175

#Unit 3. Fundamental Processes

Each set of ter sites allows a replication fork into the termination region, but does not allow it out the other side.For example, replication fork 1 can pass through terC and terB into the region, but it cannot continue past terE, -D, and -A. This arrangement creates a "replication fork trap."

TLS Online TPP Program

#Id: 3176

#Unit 3. Fundamental Processes

 mtDNA replication and segregation to daughter mitochondria is stochastic.