Difference of virulence in causing metritis in horses between heavily encapsulated, less heavily encapsulated and non-capsulated strains of Klebsiella pneumoniae capsular type 1.

Difference of Virulence in Causing Metritis in Horses between Heavily Encapsulated, Less Heavily Encapsulated and Non-capsulated Strains of Klebsiella Pneumoniae Capsular Type

Reduction of capsular polysaccharide production in Klebsiella pneumoniae by sodium salicylate.

Heavily encapsulated Klebsiella pneumoniae (serotypes 1 and 2) was cultured in the presence of sodium salicylate. The addition of salicylate (2 to 30 micrograms/ml) progressively decreased the amount of capsular polysaccharide produced by all strains without significantly inhibiting cell growth. Further addition of salicylate (50 to 200 micrograms/ml) was progressively inhibitory to cell growth...

Identification of Capsular Serotypes K1 and K2 in Clinical Isolates of Klebsiella Pneumoniae in North of Iran

ABSTRACT          Background and Objectives: Klebsiella pneumoniae is one of the most important nosocomial pathogens. Its capsular polysaccharide is considered as the first and most important virulence factor of this bacterium. This study aimed to investigate the presence of capsular serotypes K1 and K2 in K. pneumoniae isolates to examine the virulence ...

Role of lung epithelial cells in defense against Klebsiella pneumoniae pneumonia.

The airway epithelium represents a primary site for the entry of pathogenic bacteria into the lungs. It has been suggested for many respiratory pathogens, including Klebsiella pneumoniae, that adhesion and invasion of the lung epithelial cells is an early stage of the pneumonia process. We observed that poorly encapsulated K. pneumoniae clinical isolates and an isogenic unencapsulated mutant in...

Effect of intrastrain variation in the amount of capsular polysaccharide on genetic transformation of Streptococcus pneumoniae: implications for virulence studies of encapsulated strains.

The degrees of competence of opaque and transparent colony variants of Streptococcus pneumoniae were compared. The transparent variants were transformed at 9- to 670-fold-higher rates than the opaque variants, independent of the DNA incorporated, due to decreased expression of capsular polysaccharide. Genetic transformation, therefore, tends to select for a less-encapsulated subpopulation.