Adhesive properties of film-forming strains of staphylococci, isolated from different compartments of the human gastrointestinal tract

Abstract

Dysbiotic disorders, realized as changes in the composition of microbiota of different biotopes, are among the most difficult conditions to cure. This is due primarily to the fact that opportunistic microorganisms that actually mediate the development of such states are characterized by an increased colonization potential, which at the first stage of penetration into a biotope is realized as adhesion to the cell surface. When a microorganism successfully realises this stage it enters into a competitive relationship with the autochthonous flora and begins to inhibit its development. Such strategy becomes especially successful if the colonist has the ability to form a biofilm. It is known that the initial stage of biofilm formation is adhesion onto the surface, therefore, the study of adhesive properties of clinical strains opens the way for understanding the initial processes of development of dysbiosis and allows for the development of preventive measures. The aim of our research was to investigate the differences in the manifestation of adhesive properties of film-forming strains of staphylococci isolated from different compartments of the human gastrointestinal tract. We established that the frequency of detection of film-forming strains of staphylococci in different compartments of the gastrointestinal tract in the norm or during the development of lesions was for Staphylococcus aureus from 23.8% to 79.4%, and for S. epidermidis from 15.4% to 100%, which indicates the significant role of these microorganisms in the development of complications at the specified biotope. It was determined that the maximal manifestation of adhesive properties was typical for biofilm-forming strains of S. epidermidis and S. aureus isolated during intestinal dysbiosis. The average values of the adhesion index were 6.00 ± 1.41 and 5.88 ± 2.22 and the index of adhesion of microorganisms was 6.61 ± 1.46 and 6.64 ± 2.48 respectively. The lowest value of these indices for film-forming strains was determined for strains of staphylococci isolated from the gastrointestinal tracts of patients suffering from food poisoning – 2.60 ± 1.14 and 2.86 ± 1.23 respectively. The obtained data suggest that the ability for biofilm-formation and a high level of adhesion indexes indicate with a high probability that a strain will cause long-lasting lesions, such as dysbiosis. The determination of these markers at the diagnostic stage will allow a broader study of the biological properties of the strain, which may be the basis for the development of an individual, optimal therapeutic scheme that conforms with the tasks of personalized medicine.

Nanocomposites with ornidazole—antibacterial and antiadhesive agents against Gram-positive and Gram-negative bacteria

“…Determination of the adhesive activity of the untreated bacterial cultures, which, thereafter, were used as a control group in comparison to the adhesivity of those after being treated with nanocomposites, allowed us to identify the tested strains as moderate-(IMA 2.51-4.0) and high-adhesive (IMA > 4.0), according to the scale described in the following studies (Minukhin et al 2013). The index of microbial adhesion equaled 3.5 for S. aureus ATCC 25923 which corresponds to the findings of other authors (Shevchenko et al 2017;Khrystian et al 2018), according to whom the above mentioned index for collection's S. aureus strains varied between 2.44 and 3.5. In the case of Gram-negative bacteria the index of the microbial adhesion differed, the tested E. coli strain ATCC 25922 was classified as moderate-adhesive (IMA = 3.62) and P. aeruginosa strain ATCC 27853 as high-adhesive (IMA = 6.09).…”