Expression of coagulin A with low cytotoxic activity by Pediococcus pentosaceus ST65ACC isolated from raw milk cheese.

AIMS: We aimed to evaluate some specific conditions for growth of Pediococcus pentosaceus ST65ACC and its bacteriocin expression through ABC transporters; to purify the bacteriocin and determine its sequence; and to evaluate the cytotoxicity potential of the purified bacteriocin(s). METHODS AND RESULTS: The results presented for growth behaviour of P. pentosaceus ST65ACC showed that the bacterial growth was slightly influenced when cultured in MRS broth with different amounts of inoculum: 1, 2, 5 and 10%. The bacteriocin activity increased when 5 and 10% inocula were used. The carbon source (glucose) used in different amounts (1, 2, 3 or 4%) had no significant effect on growth and bacteriocin production. The studied strain P. pentosaceus ST65ACC was able to metabolize xylooligosaccharide (XOS) as the sole carbon source, resulting in the production of an antimicrobial peptide. The genes involved in the ABC transport system and sugar metabolism of P. pentosaceus ST65ACC were expressed at different levels. The bacteriocin produced by P. pentosaceus ST65ACC was partially purified by precipitation with ammonium sulphate (40% saturation), followed by reversed-phase liquid chromatography, resulting in the identification of an active bacteriocin. Tandem mass spectrometry was used to identify the partial sequence KYYGNGVTCGKHSCSVDWGK sharing high similarity to coagulin A. The semi-purified bacteriocin had low cytotoxicity based on estimated values for maximal nontoxic concentration (MNC) and cytotoxicity concentration (CC50 ). CONCLUSIONS: The bacteriocin produced by P. pentosaceus ST65ACC is similar to coagulin, with low cytotoxicity, strong antimicrobial activity and possible additional metabolite routes in the producer cell. In addition to MRS broth, bacteriocin was produced also in medium containing XOS (as the single carbon source). SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report of evaluation of the role of ABC transporters in the expression of bacteriocin by P. pentosaceus, cultured in MRS and XOS.

[Profundoplasty in treatment of patients with chronic lower limb ischaemia]. / Profundoplastika v lechenii bol'nykh s khronicheskoi ishemiei nizhnikh konechnostei.

Occlusion of the superficial femoral artery is a frequently encountered pathology in peripheral vascular disease. In patients with chronic lower limb ischaemia in a lesion of crural arteries the results of femoropopliteal bypass grafting are unsatisfactory, therefore, the deep femoral artery becomes the decisive collateral pathway for perfusion of the lower extremity. PATIENTS AND METHODS: The study included a total of 166 patients presenting with TASC II B, C and D type lesions of the femoropopliteal segment after profundoplasty, who were subdivided into 3 groups depending on the stage of chronic lower limb ischaemia: Group 1 - 95 patients with stage II B, Group 2 - 56 patients with stage III, and Group 3 - 15 patients with stage IV. RESULTS: Five years after profundoplasty in Group 1 amputation was avoided in 90 patients (94.7%) in Group 2 - in 47 patients (83.9%), where p=0.028. During 14 months in Group 3 due to unsatisfactory distal bed 15 patients (100%) were subjected to amputation of the operated lower limb at various levels. The binary logistic regression analysis of the diameter of the deep femoral artery (p=0.045, OR=0.139) and the state of the distal arterial bed (p=0.02, OR=9.341) demonstrated that the diameter of the artery directly influenced the outcome of profundoplasty within up to 5 years. CONCLUSION: Profundoplasty is an effective operation from the point of view of clinical and haemodynamic outcomes for patients presenting with occlusion of the superficial femoral artery and stenosis of the deep femoral artery with stage IIB and III chronic lower limb ischaemia. The diameter of the deep femoral artery and the condition of the arterial bed are the factors influencing the results of profundoplasty within up to 5 years.