Mcr phenotypes reported in [Raleigh, E.A. et al. (1988) Nucl. Acids Res., 16, 1563-1575, References 7 in Restriction of Foreign DNA by E. coli K-12] except those denoted with asterisks. Mrr phenotypes determined at NEB except DH10B (11). EcoKI phenotypes sometimes inferred from genotype.

Table Notes:

( )  phenotype inferred from that of ancestral or descendant strains.
?  phenotype not tested.
D  mutation present is known to be a large deletion.
‡  These strains were formerly thought to carry the mcrB allele present in E.coli B. They are now known to carry an extensive deletion of mrr ^-hsd ^-mcrBC (ref. 6; M. Noyer-Weidner, personal communication; J. Kelleher, personal communication).
*  Phenotypes reported in one of references 8-12.
**  Phenotypes determined at New England Biolabs, Inc.
Bule catalog numbers in paretheses indicate strains that are available upon request from New England Biolabs at no charge with an order or for the cost of shipping if ordered separately.
***  C600 lines obtained from different sources give different results. The original strain, and that obtained from the E. coli Genetic Stock Center (Yale University) are McrA⁺; derivatives traceable to the Brenner laboratory are McrA^- (21).