Final answer:
In E. coli, the origin of replication is signaled by a specific DNA sequence recognized by initiator proteins, where enzymes like helicase and primase play crucial roles in the replication process.
Step-by-step explanation:
The location of the origin of replication in E. coli is signaled by a specific DNA sequence recognized by initiator proteins. This sequence is known as oriC, which is approximately 245 base pairs in length and rich in adenine-thymine (AT) sequences. Proteins bind to this site to initiate replication, with helicase unwinding the DNA and forming replication forks that extend bi-directionally. The replication process involves various other proteins and enzymes, including primase, which synthesizes RNA primers necessary for DNA polymerase to begin synthesis of the new DNA strand.