All the conveniences of bacterial cloning plasmids are incorporated into binary vectors, such as multiple unique restriction sites in the T-DNA region to facilitate subcloning, the lacZ gene for blue–white screening and a λ cos site for preparing cosmid libraries.

Examples of Binary vector system

pBIN19- one of the first binary vectors developed in 1980s and was widely used.

pGreen- A newly developed vector with advanced features than pBIN19.

Both the vectors contain Lac Z gene for blue-white screening of recombinants. The reduction of size of pGreen is due to the presence of pSa origin of replication. An essential replicase gene is housed on a second plasmid, called pSoup which functions in trans. All conjugation functions have also been removed, so this plasmid can only be introduced into Agrobacterium.

 

Features	pBIN19	pGreen
Size	Large (11777bp)	Small (<5bp)
Position of Selectable marker	Situated near RB. Due to origination of transfer from RB, transfer of selectablemarker before gene of interest will result in plants expressing selectable marker but not with transgene or truncated version.	Situated next to LB
Restriction sites	Limited	Much larger MCS with many restriction sites.

Table 5-4.4.3: Comparison between Binary vectors pBIN19 and pGreen