Cosmid -

A DNA sequence that allows the cosmid to replicate independently within a bacterial host, just like a standard plasmid.

They help scientists organize DNA fragments in the correct order along a chromosome. cosmid

If you are importing this into a genome browser or database, here is the GFF3 entry: A DNA sequence that allows the cosmid to

| Start | End | Feature Name | Description | | :--- | :--- | :--- | :--- | | 1 | 12 | | Lambda phage cohesive end site ($\cos L$); required for packaging DNA into phage particles. | | 250 | 1,100 | ori | Origin of replication (ColE1); allows the vector to replicate as a plasmid inside the bacterial host. | | 1,500 | 2,361 | AmpR | Beta-lactamase gene conferring resistance to ampicillin; used for selecting transformed bacteria. | | 2,400 | 2,800 | MCS | Multiple Cloning Site; contains unique restriction sites (e.g., BamHI, EcoRI, HindIII) for DNA insertion. | | 3,500 | 3,512 | cos site | Second lambda phage cohesive end site ($\cos R$); pairs with the first site to form the circular packaging signal. | | | 250 | 1,100 | ori |