Proteomic study of Enterococcus durans LAB18S growing on prebiotic oligosaccharides.

This study evaluates the influence of prebiotic carbohydrates, namely fructooligosaccharides (FOS) and galactooligosaccharides (GOS), on the protein expression of Enterococcus durans LAB18S. The strain was cultivated in 10 g L-1 FOS, GOS or glucose (control) and cellular proteins were extracted for mass spectrometry analysis. A total of 771 proteins were identified and 135 E. durans proteins were validated by the Scaffold algorithm. The proteins were functionally categorized according to Gene Ontology terms. Both FOS and GOS were used as carbon source by E. durans LAB18S, upregulating the production of proteins that may be associated with intestinal mucosa adhesion, carbohydrate and nitrogen metabolism, and stress response. Cells grown with GOS showed an increased expression of the cell division protein divIVA, EF-Tu and glyceraldehyde 3-phosphate dehydrogenase that have been associated with epithelial cell adhesion. The use of FOS stimulated the production of proteins related to amino acid metabolism and energy conversion, and ClpX protein, which plays an important role in protein turnover. The results of this study indicate that FOS and GOS can be metabolized by E. durans and stimulate the microorganism to produce proteins related to some desirable characteristics for a probiotic strain.