Plasmids are circular doublestranded DNA molecules that can replicate autonomously in either a prokaryotic or eukaryotic host. Naturally occurring plasmids have been identified in representative members of virtually all taxonomic groups of bacteria. Many of them are not confined to a single host but may transfer themselves to other - even very distantly related - species. Moreover the use of transformation procedures allows experimental evaluation of the broad-host range character in conditions circumventing natural ecological barriers.
The advent of genetic engineering techniques has dramatically increased the importance of studying and catalogueing plasmids. Indeed, recombinant plasmids have developed into major tools in all areas of fundamental molecular biology as well as in applied biotechnology.

The BCCMTM/LMBP collection holds natural as well as recombinant plasmids.
The latter constitute the vast majority of the stocked items. They are subdivided into two groups: "vectors" and "cloned genes". The vector group consists of general purpose cloning vectors and highly sophisticated expression vectors designed for expression of cloned genes in prokaryotes, yeasts and fungi and higher eukaryotic (insect and mammalian) cells. The group "cloned genes" consists of recombinant constructs which carry cloned gene sequences coding for a variety of proteins from eukaryotic as well as prokaryotic sources, such as interferons, interleukins, influenza proteins, phage proteins, ligases etc.

About 1000 plasmids are already described in full molecular detail, whenever possible at the DNA sequence level.
Functional features, such as cloned genes, promoters, ribosome binding sites, transcription terminators and other features can be displayed on a graphical, circular map, which can be visualized on a color screen, printed and/or plotted. These features are described in detail in an accompanying data sheet, containing also other useful information such as full details on the construction of the plasmid, its application areas, required host strains, selection markers and restriction sites. The constructed nucleotide sequence can be exported to a file, suitable for several DNA analysis packages, allowing restriction site analysis, translation, homology searches, etc. Moreover, the standardized database format offers the possibility of intelligent searching for the most appropriate plasmid for any given application.

Last update: 5 July 1999
Contact : F. Guissart