Of these, 150 strains are available from NCTC in the form of bacterial DNA, supplied at 2 μg, making them suitable for whole genome sequencing amongst other molecular applications.

The NCTC was founded in 1920 with John Charles Grant Ledingham, who was previously chief bacteriologist at the Lister Institute, serving as its first director.

[1] The first strain to be added to the collection—termed NCTC1—was an isolate of Shigella flexneri, a causative agent of bacillary dysentery, cultured in 1915 from a man believed to have been a British soldier in the First World War.

[2] Mabel Rhodes, the first assistant curator of the NCTC, recounted that the collection's initial premises at the Lister Institute "contained nothing but a telephone" and that bacteriological equipment had to be borrowed from other departments.

Safety protocols at the time were poor, and during the early years of the organisation three staff members contracted tularemia.