Culture Collections

NCTC Control Strains for UK Standards for Microbiological Investigations (SMIs)


Salmonella 2


The UK Health Security Agency (UKHSA) in conjunction with its partner organisations develops SMIs to help to assure equivalence of investigation strategies in different laboratories; all the SMI Test Procedures (TPs) for bacteriology stipulate the use of control strains from the National Collection of Type Cultures (NCTC).  Controls are necessary to help demonstrate that laboratory procedures are being operated and interpreted correctly.

For further information or to download any of the Standards for Microbiological Investigations go to the UK Standards for Microbiology Investigations webpage

Culture Collections now provide a cost effective means for clinical microbiology laboratories to update their stock cultures of the 17 NCTC strains needed for the SMI TPs in a single order. The SMI TP NCTC set (17 strains) includes all the 17 controls listed below:


Species name
NCTC number
SMI TP control strain information

Acinetobacter Iwoffii


negative control for TP21 (motility) and TP27 (fermentation of glucose)

Clostridium difficile  11204 negative control for TP22 (Nagler)
Clostridium perfringens  8359 positive control for TP22 (Nagler)
Enterococcus faecalis  12697 positive control for TP2 (aesculin hydrolysis)
Escherichia coli  10418 positive control for TP19 (indole), TP24 (ONPG (ß-galactosidase)) for Enterobacteriaceae, TP27 (fermentation of glucose) and TP30 (potassium hydroxide)

negative control for TP26 (oxidase) and TP36 (urease)

Haemophilus influenzae  11931

positive control for TP38 (x and v factors)

negative control for TP29 (porphyrin synthesis (ala))

Haemophilus parainfluenzae  10665

positive control for TP29 (porphyrin synthesis (ala))

negative control for TP38 (x and v factors)


Micrococcus luteus


positive control for TP27  (oxidation of glucose)

Neisseria gonorrhoeae  8375 negative control for TP24 (ONPG (ß-galactosidase)) for Neisseria spp.
Neisseria lactamica  10617 positive control for TP24 (ONPG (ß-galactosidase)) for Neisseria spp.
Proteus mirabilis  10975 positive control for TP21 (motility) and TP36 (urease)

negative control for TP19 (indole) and TP 24 (ONPG) (ß-galactosidase)) for Enterobacteriaceae

Pseudomonas aeruginosa  10662 positive control for TP26 (oxidase) and TP27 (oxidation of glucose)
Staphylococcus aureus  6571 positive control for TP8 (catalase), TP10 (coagulase), TP12 (deoxyribonuclease), TP27  (fermentation of glucose) and TP34 (thermonuclease)

negative control for TP30 (potassium hydroxide)

Staphylococcus haemolyticus  11042 negative control for TP10 (coagulase), TP12 (deoxyribonuclease) and TP34 (thermonuclease)
Streptococcus agalactiae  8181 negative control for TP2 (aesculin hydrolysis)
Streptococcus mitis  10712 negative control for TP5 (bile solubility), TP8 (catalase) and TP25 (optochin)
Streptococcus pneumoniae  12977 positive control for TP5 (bile solubility) and TP25 (optochin)



Back to top
Copyright © Public Health England.

Please confirm your country of origin from the list below.