As addressed by the NIH Guidelines for Research Involving Recombinant DNA Molecules (NIH Guidelines), particular research with E. coli K-12 derivatives is exempt from the requirements of the NIH Guidelines.  

Ancestral E. coli K-12 

Strain Designation

Origin or Collection

58Stanford Strain
679Stanford strain
WG1Wisconsin strain

E. coli K-12 Derivatives

Strain DesignationOrigin or CollectionStrain DesignationOrigin or Collection
5KLab strainJM83Lab strain
58-161Lab strainJM101Lab strain
AB284Lab strainMB408Lab strain
AB311Lab strainP678Lab strain
AG1Lab strainPA 309Lab strain
C600Lab strainSURELab strain
Cavalli HfrLab strainTG1Lab strain
DH1Lab strainW208Lab strain
Dh5aLab strainW945Lab strain
DP50Lab strainW1485Lab strain
EMG2Lab strainW3110Lab strain
H1443Lab strainWA704Lab strain
HB101Lab strainXL1-BlueStratagene
Hfr3000Lab strainXLOLRStratagene
Hfr 3000 X74Lab strainY10Lab Strain
HMS 174NovegenYN2980Lab Strain
JC9387Lab strain  

For additional strains and information regarding K-12 derivatives please go to the following website:
 http://cgsc.biology.yale.edu/
 

NOTE: E. coli Laboratory Strains NOT Derived from K-12

The following E. coli laboratory strains are not derived from K-12 and therefore any research utilizing these strains is not exempt from the NIH Guidelines.

Strain DesignationOrigin or Collection
BLaboratory strain
B-3Laboratory strain
BL21Novagen
B/R Laboratory strain
CLaboratory strain
TOPPStratagene

Reference

Kuhnert, P., J. Nicolet, J. Frey.  1995.  Rapid and accurate identification of Escherichia coli K-12 strains.  Applied and Environmental Microbiology.  61:4135-4139.