TABLE 1.
Bacterial strains used in this study
| Strain | Relevant characteristics |
S. pneumoniae nan genea
|
Source or reference | ||
|---|---|---|---|---|---|
| nanA | nanB | nanC | |||
| N. meningitidis N3 | MC58C3, type B unencapsulated mutant | 12 | |||
| H. influenzae H122 | Nontypeable clinical isolate | This study | |||
| S. pneumoniae | |||||
| P2 | R6, unencapsulatedb mutant of D39 | + | + | − | 20 |
| P394 | Type 4 genome sequence strain | +c | + | + | 14 |
| P1247 | D39ΔnanA | − | + | − | 18 |
| P1252 | Type 21 clinical isolate | + | − | − | This study |
| P1253 | P1252ΔnanA | − | − | − | This study |
a
The presence of nanB was determined by PCR and Southern hybridization. The presence of nanC was determined by PCR (data not shown). +, present; −, absent.
b
The presence of capsule had no apparent effect on neuraminidase activity in this study.
c
Secreted fragment due to frameshift mutation upstream of the C-terminal cell surface-anchoring domain.