Nebraska Transposon Mutant Library

In an effort to enhance the research capabilities of the staphylococcal research community, the CSR has generated a collection of sequence-defined transposon (Tn) insertion mutants of Staphylococcus aureus (S. aureus) termed the Nebraska Transposon Mutant Library. This collection of strains contains mutant derivatives of USA300 LAC in which individual genes have been disrupted by the insertion of the mariner Tn bursa aurealis. By determining the nucleotide sequences of the junction fragments containing the end of the Tn and the flanking DNA, the insertion sites have been identified for each mutant in the collection. In collaboration with Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA), these mutants have been made available to the staphylococcal research community. The ultimate goal is to generate mutations in each of the approximately 2,000 non-essential genes in the genome and make these mutants available for experimental analysis.

The Nebraska Library
The Nebraska Transposon Mutant Library is a sequence-defined Tn insertion library of S. aureus in which each of the approximately 2,000 non-essential genes in the genome are disrupted via mariner Tn mutagenesis. S. aureus mutants currently available for distribution are shown in the list below. The data associated with each mutant were obtained directly from the USA300_FPR3757 genome sequence (NCBI reference sequence NC_007793). This list will be updated periodically as more mutants are added to the collection. To utilize the library, you will need Internet Explorer 9 or the latest version of Firefox, Chrome, or Safari.

Parental Strain
The strain used to generate the Nebraska Library was derived from S. aureus USA300 LAC, a highly characterized community-associated methicillin-resistant S. aureus (MRSA) strain isolated from the Los Angeles County jail (ref). This strain contains three small plasmids, one encoding resistance to tetracycline and another encoding erythromycin resistance. The third plasmid is cryptic. For ease of genetic manipulation and to avoid interference with subsequent transposition events involving bursa aurealis, all three plasmids were cured, yielding strain USA300 JE2 that was used for all subsequent Tn mutagenesis experiments.

Funding Sources
The construction of the Nebraska Library was made possible by funding from the Department of Defense (DOD). Storage and subsequent dissemination of the library, as with all isolates in the NARSA collection is funded by the National Institutes of Health (NIH).