Scarab Genomics offers its patented Clean Genome® E. coli strains under a limited license for research/evaluation purposes. When placing an order choose No Modifications to the Chromosome or Modifications to the Chromosome.  The No Modifications to the Chromosome option allows product use for research only.  The Modifications to the Chromosome option allows for specific changes to the chromosome with a Research License Agreement.  The Research License Agreement will be sent to you after you provide the specific information requested.