Evaluation of Two Supplemented Culture Media for Long-Term, Room-Temperature Preservation of Streptococcus pneumoniae Strains
Table 2
Description of the tests performed.
Test
Strains
Agar
Evaluations
Subcultures
Recipient
Test 1 (pilot study) (6 months)
Total = 1 S. pneumoniae ATCC 49619
TH-HYC TH-SYC
(i) Viability of all subcultures (monthly) (ii) Amount of viable CFU in 1 subculture per strain in both media (weekly)
per strain Total: 10 per medium
Petri dishes (15 × 100 mm)
Test 2 Clinical and nasopharyngeal isolates (4 months)
Total = 5 Meningitis isolate
Conjunctivitis isolate
Nasopharyngeal strains S. pneumoniae ATCC 49619
TH-HYC TH-SYC
(i) Viability of all subcultures (monthly) (ii) Amount of viable CFU in 1 subculture per strain in both media (weekly) (iii) Maintenance of serotypes, optochin susceptibility, reaction with agglutination test, and patterns of resistance in all subcultures (at the end of the test)
per strain Total: 50 per medium
Petri dishes (15 × 100 mm)
Test 3 several serotypes and MLST types (2 months)
Total = 16 Nasopharyngeal strains S. pneumoniae ATCC 49619
TH-HYC
(i) Viability of all subcultures (at the end of the test) (ii) Maintenance of optochin susceptibility, reaction with agglutination test, patterns of resistance, and presence of macrolide resistant genes in all subcultures (at the end of the test)
per strain Total: 48
Safe-lock microtubes (1.5 mL)
Test 4 several serotypes and MLST types (6 months)
Total = 16 Nasopharyngeal strains S. pneumoniae ATCC 49619
TH-HYC
(i) Viability of all subcultures (at the end of the test) (ii) Maintenance of optochin susceptibility, reaction with agglutination test, patterns of resistance, and presence of macrolide resistant genes in all subcultures (at the end of the test)
