Table 2

Identification of 18 C. tuberculostearicum strains by 16S rRNA gene sequencing, 18 strains by the API Coryne System,a and 12 strains by MALDI-TOF MS

No. of strains16S rRNA gene sequencingAPI CoryneAvg MALDI-TOF MS scoreb ± SD
Numerical codeFirst choice listed (% IDd probability, T value)ID interpretationNormal protocolShort extraction protocolFull extraction protocol
5C. tuberculostearicum4100305C. macginleyi (85.6, 0.79)Good ID on genus level1.644 ± 0.311.917 ± 0.082.045 ± 0.07
2C. tuberculostearicum4100304C. jeikeium (59.2, 0.64)Acceptable ID on genus levelNDcNDND
2C. tuberculostearicum5100304C. macginleyi (97.5, 0.79)Good ID1.486 ± 0.051.863 ± 0.142.076 ± 0.10
2C. tuberculostearicum7100305CDC group G (83, 0.86)Very good ID on genus level1.715 ± 0.371.82 ± 0.242.007 ± 0.11
2C. tuberculostearicum7100304CDC group G (43.5, 0.69)Good ID on genus level1.633 ± 0.121.894 ± 0.041.955 ± 0.02
1C. tuberculostearicum6100305CDC group G (96.7, 0.98)Good ID1.8931.8021.85
1C. tuberculostearicum2100305CDC group G (86.9, 1)Excellent ID on genus levelNDNDND
1C. tuberculostearicum0100305C. macginleyi (84.3, 0.82)Very good ID on genus levelNDNDND
1C. tuberculostearicum4000304C. accolens (90.5, 0.64)Doubtful profileNDNDND
1C. tuberculostearicum6100304C. jeikeium (60, 0.79)Low selectivityNDNDND
  • a C. tuberculostearicum is not included in the API Coryne database.

  • b Interpretation of score values: ≥2.300, highly probable identification to the species level; 2.000 to 2.299; probable identification to the species level, 1.700 to 1.999; probable identification to the genus level; <1.700, no reliable identification.

  • c ND, not done.

  • d ID, identification.