laboratory diagnostic - testing and comparison - biological samples and assessment reports - quality control - internal - reference strains - qualitative - Escherichia coli (mcr-1), equivalent collections NCTC 13846, recomended by EUCAST, vial x10 discs, keep in the freezer, C.F.U between 10^6-10^9, freeze-dried, water-soluble, used in solid or liquid media, code L37RS1084-10, todylaboratories®