[Microbial "friend-foe" identification in human intestine microsymbiocenosis].
OBJECTIVE
Development of methodical approach of evaluation of microbial "friend-foe" identification in human intestine microsymbiocenosis.


METHODS
9 bifidobacteria cultures (dominants) and 18 opportunistic microorganism strains (associants) isolated from patients during examination for intestine dysbiosis and identified by conventional methods were used. Evaluation of microbial "friend-foe" identification in microsymbiocenosis was performed by author developed technique that is based on determination of growth factors (GF), anti-lysozyme activity (ALA) and formation of biofilms (BFF) of associants co-incubated with exometabolites of dominants. GF, ALA, BFF were studied photometrically (Bukharin O.V., 1999, 2009; O'Toole G.A., 2000). The data were statistically analyzed by Fisher-Student criteria.


RESULTS
The detected opposite (increase/reduction) phenomenon of the "dominant-associant" pair allowed realization of the "friend-foe" identification in microsymbiocenosis. Associants (E. coli and Enterococcus faecium) were "friend" species, in which bifidobacteria exometabolites did not change growth properties and stimulated ALA (by 17,5--32%) and BFF (by 25 - 39%). Associants (Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Candida albicans) were "foe" microsymbiont species, in which bifidoflora exometabolites decreased GF (by 20,7--68%), ALA (by 22,7--54%) and BFF (by 22,5 --39%).


CONCLUSIONS
Indigenous microflora during microsymbiocenosis formation can participate in "friend-foe" identification, the basis of which is determined by microsymbiont exometabolites. The data obtained open a perspective of understanding mechanisms of intramicrobial interactions and can be used for both diagnostics and optimal selection of "candidates" during creation of new probiotics and synbiotics.
O V
OV
Bukharin
N B
NB
Petrunova
D018441:Biofilms / Q000254:growth & development; D002176:Candida albicans / Q000302:isolation & purification / Q000502:physiology*; D003470:Culture Media; D006090:Gram-Negative Bacteria / Q000302:isolation & purification / Q000502:physiology*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification / Q000502:physiology*; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D059013:Microbial Consortia; D019936:Probiotics / Q000302:isolation & purification / Q000378:metabolism*; D053038:Quorum Sensing / Q000502:physiology*; D012107:Research Design; D013559:Symbiosis / Q000502:physiology*
D003470:Culture Media