E. coli K-12 is well established as a preferred host for commercial production of recombinant DNA products including enzymes, vaccines, metabolites and DNA itself. The complete genome sequence of the E. coli bacterium has now been determined and it shows the presence of many genes that are clearly unnecessary for production purposes and which are arguably detrimental. These include genes encoding phage remnants, adhesins, toxins and ORFs in pathogenicity islands which if activated could adulterate the recombinant product with dangerous substances. Transposible elements and other forms of selfish DNA that render the E. clol genome unstable could also cause difficulties with quality control. Some genes whose expression is simply unnecessary are therefore potentially wasteful. To improve the situation we have deleted over 14% of the E. coli K-12 genome in 39 segments. The reduced genome strain grows at a normal rate in minimal medium. By design it lacks all transposible elements, most candidates for toxic products and many seemingly unnecessary genes. A further reduction of the genome to 19.4% is in progress. In this research we propose to study the properties of the reduced genome E. coli relevant to the use as a production host by comparing the yield, purity and stability of a test product, Green Fluorescent Protein with the undeleted control strains DH10B and the parent MG1655. We also plan to measure the yield of DNA, and mutation frequency, and gene expression levels through DNA microarrays.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Small Business Innovation Research Grants (SBIR) - Phase I (R43)
Project #
1R43AI055077-01A2
Application #
6833241
Study Section
Special Emphasis Panel (ZRG1-SSS-Y (10))
Program Officer
Schmitt, Clare K
Project Start
2004-07-01
Project End
2004-12-31
Budget Start
2004-07-01
Budget End
2004-12-31
Support Year
1
Fiscal Year
2004
Total Cost
$100,000
Indirect Cost
Name
Scarab Genomics, LLC
Department
Type
DUNS #
105975036
City
Madison
State
WI
Country
United States
Zip Code
53713