As of February 2013, there are over 65,000 PSI plasmids in DNASU
- PSI:Biology-MR Information Portal
- PSI:Biology-MR Plasmid Search
- PSI:Biology-MR Empty Vectors
- PSI Plasmid Highlights
- Plasmid of the Month
- Functional Sleuth
- Additional PSI Resources
The PSI comprises a consortium of institutions, each of which focuses on a unique set of targets or protein type (e.g. eukaryotic proteins or membrane proteins). Each PSI Center has created thousands of plasmid clones containing genes or fragments of genes to be used for protein expression, purification, crystallization and structure determination. The PSI- Materials Repository, now the PSI:Biology-Materials Repository (PSI:Biology-MR) was established in 2006 with the mission of storing, maintaining and distributing the tens of thousands of plasmid clones produced by PSI researchers.
The MR stores the physical samples along with plasmid annotation, which includes the insert sequence, vector information, vector maps and sequences. Additional annotations are assembled through the PSI Structural Biology Knowledgebase and other resources to facilitate cross referencing of the plasmid to relevant experimental and structural data. Combined, this creates a valuable resource that can be used by non-PSI researchers to determine the biological functions of these genes, many of which are hypothetical genes or genes of unknown function.