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Clonal success of piliated penicillin nonsusceptible pneumococci

Sjoestroem, K.; Blomberg, C.; Fernebro, J.; Dagerhamn, J.; Morfeldt, E.; Barocchi, M. A.; Browall, S.; Moschioni, M.; Andersson, M. and Henriques, F., et al. (2007) In Proceedings of the National Academy of Sciences 104(31). p.12907-12912
Abstract
Antibiotic resistance in pneumococci is due to the spread of strains belonging to a limited number of clones. The Spain(9v)-3 clone of sequence type (ST)156 is one of the most successful clones with reduced susceptibility to penicillin [pneumococci nonsusceptible to penicillin (PNSP)]. In Sweden during 2000-2003, a dramatic increase in the number of PNSP isolates was observed. Molecular characterization of these isolates showed that a single clone of sequence type ST156 increased from 40% to 80% of all serotype 14, thus causing the serotype expansion. Additionally, during the same time period, we examined the clonal composition of two serotypes 9V and 19F: all 9V and 20% of 19F isolates belonged to the clonal cluster of ST156, and overall... (More)
Antibiotic resistance in pneumococci is due to the spread of strains belonging to a limited number of clones. The Spain(9v)-3 clone of sequence type (ST)156 is one of the most successful clones with reduced susceptibility to penicillin [pneumococci nonsusceptible to penicillin (PNSP)]. In Sweden during 2000-2003, a dramatic increase in the number of PNSP isolates was observed. Molecular characterization of these isolates showed that a single clone of sequence type ST156 increased from 40% to 80% of all serotype 14, thus causing the serotype expansion. Additionally, during the same time period, we examined the clonal composition of two serotypes 9V and 19F: all 9V and 20% of 19F isolates belonged to the clonal cluster of ST156, and overall approximate to 50% of all PNSP belonged to the ST156 clonal cluster. Moreover, microarray and PCR analysis showed that all ST156 isolates, irrespective of capsular type, carried the rlrA pilus islet. This islet was also found to be present in the penicillin-sensitive ST162 clone, which is believed to be the drug-susceptible ancestor of ST156. Competitive experiments between related ST156 serotype 19F strains confirmed that those containing the rlrA pilus islet were more successful in an animal model of carriage. We conclude that the pilus island is an important biological factor common to ST156 isolates and other successful PNSP clones. In Sweden, a country where the low antibiotic usage does not explain the spread of resistant strains, at least 70% of all PNSP isolates collected during year 2003 carried the pilus islet. (Less)
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keywords
Streptococcus pneumoniae, clonal expansion, pilus
in
Proceedings of the National Academy of Sciences
volume
104
issue
31
pages
12907 - 12912
publisher
National Acad Sciences
external identifiers
  • wos:000248603900057
  • scopus:34547924465
ISSN
1091-6490
DOI
10.1073/pnas.0705589104
language
English
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yes
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f5c65d96-29a5-4083-99ca-b92765db11ad (old id 689827)
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2007-12-19 16:22:24
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2017-10-29 03:35:50
@article{f5c65d96-29a5-4083-99ca-b92765db11ad,
  abstract     = {Antibiotic resistance in pneumococci is due to the spread of strains belonging to a limited number of clones. The Spain(9v)-3 clone of sequence type (ST)156 is one of the most successful clones with reduced susceptibility to penicillin [pneumococci nonsusceptible to penicillin (PNSP)]. In Sweden during 2000-2003, a dramatic increase in the number of PNSP isolates was observed. Molecular characterization of these isolates showed that a single clone of sequence type ST156 increased from 40% to 80% of all serotype 14, thus causing the serotype expansion. Additionally, during the same time period, we examined the clonal composition of two serotypes 9V and 19F: all 9V and 20% of 19F isolates belonged to the clonal cluster of ST156, and overall approximate to 50% of all PNSP belonged to the ST156 clonal cluster. Moreover, microarray and PCR analysis showed that all ST156 isolates, irrespective of capsular type, carried the rlrA pilus islet. This islet was also found to be present in the penicillin-sensitive ST162 clone, which is believed to be the drug-susceptible ancestor of ST156. Competitive experiments between related ST156 serotype 19F strains confirmed that those containing the rlrA pilus islet were more successful in an animal model of carriage. We conclude that the pilus island is an important biological factor common to ST156 isolates and other successful PNSP clones. In Sweden, a country where the low antibiotic usage does not explain the spread of resistant strains, at least 70% of all PNSP isolates collected during year 2003 carried the pilus islet.},
  author       = {Sjoestroem, K. and Blomberg, C. and Fernebro, J. and Dagerhamn, J. and Morfeldt, E. and Barocchi, M. A. and Browall, S. and Moschioni, M. and Andersson, M. and Henriques, F. and Albiger, Barbara and Rappuoli, Rino and Normark, S. and Henriques-Normark, B.},
  issn         = {1091-6490},
  keyword      = {Streptococcus pneumoniae,clonal expansion,pilus},
  language     = {eng},
  number       = {31},
  pages        = {12907--12912},
  publisher    = {National Acad Sciences},
  series       = {Proceedings of the National Academy of Sciences},
  title        = {Clonal success of piliated penicillin nonsusceptible pneumococci},
  url          = {http://dx.doi.org/10.1073/pnas.0705589104},
  volume       = {104},
  year         = {2007},
}