View source for Plasmid backbones/Version 5/Features

#A complete BioBrick&reg; cloning site for easy cloning and assembly of BioBrick&reg; parts.
#A low or medium copy replication origin to reduce consumption of cellular resources during device or system operation.
#Forward and reverse terminators both upstream and downstream of the BioBrick&reg; cloning site to insulate the vector from read-through transcription originating in the cloned BioBrick&reg; device or system and to insulate the cloned BioBrick&reg; system from the vector.
#Stop codons in all reading frames to prevent inadvertent translation into or out of the BioBrick cloning site.
#Primer binding sites for the standard BioBrick&reg; verification primers VF2 ([[Part:BBa_G00100|BBa_G00100]]) and VR ([[Part:BBa_G00101|BBa_G00101]]).  These primers are located for convenient sequencing and [http://openwetware.org/wiki/Colony_PCR screening by colony PCR] of cloned BioBrick&reg; devices and systems.

Plasmid backbones are distributed by the Registry with a default insert.  There are just a handful of default plasmid inserts used in the Registry.  All of the available plasmid backbones include the RFP expression cassette ([[Part:BBa_J04450|BBa_J04450]]) as the default plasmid insert within the BioBrick&reg; cloning site.  The RFP cassette enables red/white screening of colonies and ensures that when assembling two BioBrick&reg; parts together, the uncut plasmid (or a plasmid that get the RFP cassette as insert) will be red on the plate whereas the correct colonies will be white.

Plasmid backbones with the plasmid insert of [[Part:BBa_I52002|BBa_I52002]] also include a high copy replication origin in the default insert.  Thus, these plasmid backbones are easily [http://openwetware.org/wiki/Miniprep/Qiagen_kit purified in large quantities].  Cloning or assembly of a BioBrick&reg; part into the BioBrick&reg; cloning site of the plasmid backbone eliminates the default insert returning the plasmid to the control of the replication origin in the plasmid backbone.