Correlation between changes in surface hydrophobicity and interaction of Streptococcus pyogenes with human polymorphonuclear leukocytes after prolonged starvation in sea water.

The aim of this research was to evaluate the persistence of virulence characteristics of Streptococcus pyogenes cells after prolonged starvation in sea water. Studies were carried out on changes in viability, alterations in the chemical composition and surface hydrophobicity and the interaction of S. pyogenes with human polymorphonuclear leukocytes (PMN) after starvation. Results showed that surface hydrophobicity decreased progressively starting after three days of starvation and was correlated with the decrease in total carbohydrate, lipid and protein content. These values correlated with a better interaction of S. pyogenes cells with the PMN, as shown by a chemiluminescence increase that reached a peak after 32 days of starvation. Furthermore, bacterial cells became more easily phagocytized and killed by human PMN.