Virulence of Streptococcus pneumoniae may be determined independently of capsular polysaccharide

Y Mizrachi Nebenzahl; N Porat; S Lifshitz; S Novick; A Levi; E Ling; O Liron; S Mordechai; R K Sahu; R Dagan

doi:10.1016/j.femsle.2004.02.003

Virulence of Streptococcus pneumoniae may be determined independently of capsular polysaccharide

FEMS Microbiol Lett. 2004 Apr 1;233(1):147-52. doi: 10.1016/j.femsle.2004.02.003.

Authors

Y Mizrachi Nebenzahl¹, N Porat, S Lifshitz, S Novick, A Levi, E Ling, O Liron, S Mordechai, R K Sahu, R Dagan

Affiliation

¹ Department of Microbiology and The Center for Cancer Research, Ben Gurion University of the Negev, Beer-Sheva 84105, Israel. ymizr@bgumail.bgu.ac.il

PMID: 15043881
DOI: 10.1016/j.femsle.2004.02.003

Abstract

Mice were inoculated intranasally with Streptococcus pneumoniae isolates of serotype 14 with different genetic backgrounds (14R, 14DW) and a capsular switch of 14R, strain 9VR (serotype 9V). Inoculation of the mice with 14R and 9VR resulted in 60% mortality. All the mice survived 14DW inoculation. No differences in lungs' bacterial loads were found 3 h following inoculation. Bacterial clearance of 5 logs was observed 48 h after inoculation with 14DW versus within 1 log 48 h after inoculation with 14R and 9VR. No significant differences in bacterial size or the capsular amount could be found between 14R and 14DW. We conclude that factor(s) in addition to the capsule, contribute to disease outcome.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bacterial Capsules* / chemistry
Colony Count, Microbial
Disease Models, Animal
Lung / microbiology
Mice
Mice, Inbred BALB C
Mice, Inbred C57BL
Pneumococcal Infections / microbiology*
Polysaccharides, Bacterial
Streptococcus pneumoniae / pathogenicity*
Survival Analysis
Virulence*

Substances

Polysaccharides, Bacterial