INFLUENCE OF NUTRIENT MEDIUM COMPOSITIONON THE PRODUCTION OF CAPSULEPOLYSACCHARIDE BY STREPTOCOCCUSPNEUMONIA 19A SEROTYPE

Aim. Evaluate accumulation of capsule
polysaccharide by Streptococcus pneumoniae 19A
strain in semisynthetic nutrient medium including
various amino acid sources. Materials and
methods. Comparative evaluation of the production
of capsule polysaccharide by the strain
belonging to one of the most widespread S.
pneumoniae serotype (19A) was performed by
using rocket immunoelectrophoresis. The bacteria
were cultivated in semisynthetic liquid
nutrient media of varying composition. Results.
Among 4 sources of nitrogen (aminopeptide,
acid and pancreatic hydrolysate of casein, soy
peptone) added to salt nutrient medium supplemented
with glucose and vitamins, casein
and soy peptone were shown to promote the
maximum synthesis of capsule polysaccharide
independently of the cultivation time. Supplementation
of the medium with sulfates of iron,
zinc and manganese, as well as pH decrease to
acid values significantly reduced the level of
capsule polysaccharide in the culture liquid. The
maximum growth of bacteria was observed at 11
hours after the start of cultivation in a 10 L
volume fermenter in semisynthetic nutrient
medium with soy peptone. Accumulation of
capsule polysaccharide in the culture liquid
continued to the end of the observation period
(24 hours) and by the end of the process reached
193 mcg/ml. Conclusion. Further study of influ
ence of vitamins, carbohydrates, CO2 concentration
on the synthesis of high molecular
capsule polysaccharide by bacteria belonging to
various pneumococcus serotypes is reasonable.

Streptococcus pneumoniae, Streptococcus pneumoniae, nutrient medium, capsule polysaccharide