[Perioperative prevention of complications in surgery of ventral hernias]. / Perioperatsionnaya profilaktika oslozhnenii v khirurgii ventral'nykh gryzh.

OBJECTIVE: To improve perioperative algorithm of prevention of complications in patients with ventral and incisional hernias via differentiated choice of mesh implants and hernia repair technique. MATERIAL AND METHODS: The study included 144 patients with abdominal wall hernia, who were divided into two representative groups. RESULTS: Original algorithms for choosing the method of hernia repair depending on type and position of mesh implant, as well as methods of perioperative prevention of complications are proposed. CONCLUSION: These algorithms significantly reduced the incidence of postoperative wound complications after sublay hernia repair and posterior separation with TAR.

Activities of Energy Metabolism Enzymes in Atlantic Salmon Salmo salar L. Smolts and Parr Grown under Different Light Regimens.

Activities of enzymes of energy and carbohydrate metabolism in muscles and the liver were studied in Atlantic salmon Salmo salar L. smolts and parr grown under continuous or natural lighting and different feeding regimens in autumn followed by a short photoperiod in winter. Enzyme activities were found to differ between test and control salmon groups and between parr and smolts sampled at the end of the winter period. Smolts grown under continuous lighting and round-the-clock feeding differed from other groups by having higher cytochrome c oxidase (COX) activity and lower aldolase activity in muscles. Differences in aerobic metabolism in muscles between parr and smolts were found to be the same in all experimental groups, COX and aldolase activities being relatively higher in smolts. The pattern of changes in enzyme activities in the liver from parr to smolts differed between different experimental groups. Based on the results, the photoperiod was assumed to affect the activities of energy metabolism enzymes in salmon juveniles and may eventually affect the completion of smoltification.

Interaction of Neutrophils and Biofilm Formed by Uropathogenic Escherichia coli Strains with Different Pathogenic Potential.

The biofilm formation by uropathogenic E. coli (UPEC) allows bacteria to avoid the influence of the host immune system that determines the pathogenesis of persistent urinary tract infections. The purpose of this work was to evaluate the mutual influence of neutrophils and biofilms formed by UPEC with different set of virulence-associated genes (VAGs). E. coli R11 and R32 strains with a wide range of virulence factors were characterized by low biofilm biomass that did not change after interaction with neutrophils. The biomass index decreased after interaction with neutrophils for strains with a limited set of pathogenicity factors (R33, R36, R45, and R44) and a "thick" biofilm. Bacterial cells and biofilm supernatants of all UPEC strains reduced viability (DiOC6(3)+/PI-) and stimulated early apoptosis (DiOC6(3)-/PI-) of neutrophils. The number of viable neutrophils was higher, while the number of apoptotic and necrotic (DiOC6(3)-/PI+) cells was lower under the action of supernatants of strains R44, R36, R45 in comparison with bacterial cells. Thus, modulation of the innate cell functions depends on the realization of the pathogenic potential of UPEC bacteria in urinary tract biofilms that determines the development of recurrent urinary tract infections.

The effect of Escherichia coli ZP strain with a conjugation-based colicin E7 delivery on growth performance, hematological, biochemical, and histological parameters, gut microbiota, and nonspecific immunity of broilers.

The Escherichia coli ZP strain (ZP) was constructed based on the known probiotic E. coli strain Nissle 1917. It was genetically modified to carry the colicin E7 synthesis gene encoding DNase on a conjugative plasmid and the colicin E7 immunity gene in the chromosome. The aim of this study was to evaluate the effects of the daily ZP per oral administration (5 × 108 or 5 × 1010 CFU per bird) on the growth performance, hematological, biochemical, histological parameters, gut microbiota, and nonspecific immunity of the 4-24 days old broilers. The ZP administration increased the abundance of genera Bacillus, Butyrivibrio, and Clostridium and did not influence the weight gain of 4-16 days old broilers. The biochemical parameters were within normal ranges for poultry in experimental and control groups. The ZP administration had no effect on the erythrocyte numbers, hemoglobin and immunoglobulin Y concentrations, but significantly increased the serum lysozyme concentration, leukocyte numbers, and reactive oxygen species production by phagocytes compared with the control group. It did not cause inflammatory changes in intestinal mucosa, Peyer's patches, and spleen. Thus, the ZP had no detrimental effects on broiler health and could be an efficient probiotic for the broiler colibacillosis prophylaxis.

Virulence potential of faecal Escherichia coli strains isolated from healthy cows and calves on farms in Perm Krai.

Cattle are a reservoir of pathogenic and potentially pathogenic Escherichia coli (E. coli) strains, which can pose a threat to human and animal health. The aim of the study was to evaluate the occurrence of 22 virulence-associated genes (VAGs), as well as the prevalence of antimicrobial drug resistance and three different bla-genes among 49 E. coli strains isolated from healthy cattle. The presence of VAGs that are common among diarrheagenic E. coli (DEC) strains and/or extraintestinal pathogenic E. coli (ExPEC) strains was determined by amplifying specific gene sequences by PCR. The following VAGs associated with DEC were found: east1 in 24.5 % of the studied E. coli strains, estI in 10.2 %, ehxA in 8.2 %, stx2 in 6.1 %, eltA in 4.1 %, estII and stx1 in 2.0 % of the studied strains. The prevalence of ExPEC VAGs was: fimH - 91.8 %, afa/draBC - 61.2 %, iutA - 44.9 %, flu - 32.7 %, sfaDE and hlyF - 30.6 %, iroN - 22.4 %, ompT and papC - 20.4 %, kpsMTII and hlyA - 18.4 %, iss - 14.3 %, usp - 2.0 %, cnf1 and iha were not detected among the studied strains. Based on the found co-occurrence of VAGs "classical", hetero-pathogenic and hybrid-pathogenic E. coli strains were found. E. coli strains isolated from cows had a higher diarrheagenic potential, whereas E. coli strains isolated from calves more frequently contained genes associated with the ExPEC pathotype. Among the studied E. coli strains, 77.6 % were resistant to ampicillin, 49.0 % to tetracycline, 20.4 % to chloramphenicol, 16.3 % to cefoperazone, 16.3 % to ceftriaxone, 16.3 % to aztreonam, 14.3 % to cefepime, 10.2 % to norfloxacin, 10.2 % to ciprofloxacin, 6.1 % to levofloxacin and 2.0 % to gentamicin. All strains were sensitive to meropenem and amikacin. 32.7 % of the studied E. coli strains were found to be multidrug resistant, as they were resistant to at least three groups of antibiotics. With PCR, the blaTEM, blaSHV, and blaCTX-M genes were detected in 100, 31.6, and 26.3 %, respectively, of strains resistant to at least one of the beta-lactam antibiotics. Thus, it was shown that the studied faecal E. coli of healthy cows and calves had a high hetero-pathogenic potential, therefore in the future molecular genetic characterization of these bacteria shall be an important part of the epizootic monitoring.

Epidemiological characteristics of uropatogenic isolates of Escherichia coli in hospitals.

The aim of the study was to evaluate the genetic affinity of uropathogenic E. coli cultures (UPEC) and to identify the major types of extended spectrum beta-lactamases (ESBL) found among nosocomial isolates. A molecular typing of UPEC (n=93) isolated from patients with urinary tract infections (UTI) who were hospitalised in nine medical facilities (MO) in Perm was performed. It was found that 69.89% of the cultures had individual RAPD/ERIC profiles, the remaining 30.10% were distributed among 13 genome groups. Most frequently blaCTX-M-1 was detected individually or in combination with other beta-lactamase genes (n=23, 79.31% of ESBL phenotype-positive isolates), genes were detected in seventeen cases (58.62%) blaTEM and/or blaOXA, the blaCMY fragment was found in only three isolates (10.34%), blaSHV was missing in this isolates. It was shown that in two thirds of the cases the pathogens of the infection process are representatives of the endogenous intestinal microbiota of the patients, in other cases an exogenous infection occurs. The proportion of "circulating" (possibly hospital) isolates in the spectrum of UTI increased in the series: therapy departments - surgery departments - intensive care units. In addition, in multidisciplinary hospitals there are conditions for cross-infections of patients, but the epidemiological chains of episodes of UTI are short and concise. It has been shown that the probability of infection with E. coli producing CTX-M or OXA enzymes is significantly higher in the intensive care unit than in surgery or therapy departments. The data obtained complement the understanding of the epidemiology of UTI caused by E. coli and can be used as an aid in the planning and implementation of methods for the prevention and control of nosocomial UTI.

[Risk factors of abdominal wound dehiscence in abdominal surgery]. / Faktory riska razvitiya eventratsii v abdominal'noi khirurgii.

OBJECTIVE: To evaluate the role of various perioperative risk factors on the incidence of abdominal wound dehiscence. MATERIAL AND METHODS: A retrospective controlled randomized trial of the risk factors of abdominal wound dehiscence was conducted in 62 patients for the period 2013- 2018. The research was performed at the Perm City Clinical Hospital No. 4. All patients were divided into two groups: the main one (n=31) with abdominal wound dehiscence in early postoperative period and the control group (n=31) without this event. Both groups were comparable by gender, age and surgical abdominal diseases. Between-group differences in numerical indicators were analyzed using Mann-Whitney U-test, qualitative variables were analyzed using contingency tables. Differences were significant at p-value <0.05. RESULTS: Incidence of abdominal wound dehiscence was similar in patients who admitted in emergency and elective fashion (p=0.54). Anemia upon admission (p=0.71), diabetes mellitus type 2 (p=1.00), COPD (p=0.13) and obesity (p=0.76) were not significant predictors of abdominal wound dehiscence. There were significant between-group differences in CRP level (p=0.04). Among intraoperative risk factors, duration of surgery (p=0.78), surgical approach (p=1.00), aponeurosis suturing technique (p=0.39) and stoma (p=0.71) did not significantly affect the incidence of abdominal wound dehiscence. In early postoperative period, abdominal wound dehiscence correlated with peritonitis (p=0.04), SSI (p<0.01) and redo laparotomy (p=0.02). CONCLUSION: Despite the variety of pre-, intra- and postoperative risk factors, only infectious postoperative complications (SSI, peritonitis) and redo surgical interventions influenced the development of abdominal wound dehiscence. Thus, the concept of abdominal wound dehiscence prevention should be inextricably associated with the concept of prevention of postoperative infectious complications from the abdominal wall and abdominal cavity.

Estimation of the bacteriocin ColE7 conjugation-based "kill" - "anti-kill" antimicrobial system by real-time PCR, fluorescence staining and bioluminescence assays.

The efficiency of the bacteriocin, colicin ColE7, bacterial conjugation-based "kill" - "anti-kill" antimicrobial system, was assessed using real-time PCR, flow cytometry and bioluminescence. The ColE7 antimicrobial system consists of the genetically modified Escherichia coli strain Nissle 1917 harbouring a conjugative plasmid (derivative of the F-plasmid) encoding the "kill" gene (ColE7 activity gene) and a chromosomally encoded "anti-kill" gene (ColE7 immunity gene). On the basis of traJ gene expression in the killer donor cells, our results showed that the efficiency of the here studied antimicrobial system against target E. coli was higher at 4 than at 24 h. Flow cytometry was used to indirectly estimate DNase activity of the antimicrobial system, as lysis of target E. coli cells in the conjugative mixture with the killer donor strain led to reduction in cell cytosol fluorescence. According to a lux assay, E. coli TG1 (pXen lux+ Apr ) with constitutive luminescence were killed already after 2 h of treatment. Target sensor E. coli C600 with DNA damage SOS-inducible luminescence showed significantly lower SOS induction 6 and 24 h following treatment with the killer donor strain. Our results thus showed that bioluminescent techniques are quick and suitable for estimation of the ColE7 bacterial conjugation-based antimicrobial system antibacterial activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial antimicrobial resistance is worldwide rising and causing deaths of thousands of patients infected with multi-drug resistant bacterial strains. In addition, there is a lack of efficient alternative antimicrobial agents. The significance of our research is the use of a number of methods (real-time PCR, flow cytometry and bioluminescence-based technique) to assess the antibacterial activity of the bacteriocin, colicin ColE7, bacterial conjugation-based "kill" - "anti-kill" antimicrobial system. Bioluminescent techniques proved to be rapid and suitable for estimation of antibacterial activity of ColE7 bacterial conjugation-based antimicrobial system and possibly other related systems.

[Comparative characteristics of uropathogenic scherichia coli strains, allocated in polyclinic and stationary conditions].

The etiological structure of urinary tract infections (UTI) is determined by the leading role of uropathogenic Escherichia coli (UPEC). The aim of the work is to study the biological properties and phylogenetic diversity of E. coli strains isolated from UTI in outpatient and inpatient patients. METHOD: s and materials. 198 clinical UPEC strains were studied, 105 of which were designated as polyclinic and 93 as nosocomial (73 are isolated from urine and 20 are from catheter surface 48 hours after hospitalization). UPEC phylogenetic groups were determined by polymerase chain reaction (quadruplex PCR) according to O. Clermont et al. (2013). RESULTS: Among polyclinic cultures, representatives of all eight recognizable phylogroups were found; strains of UPEC phylogroup B2 (37.1%), E (13.3%) and F (8.6%) were most often found. Nosocomial cultures in almost 90% of cases belonged to the phylogroup B2, to which all the catheter-associated strains were assigned. The E. coli of the phylogroup B2, both in the mono-species and in the polymicrobial associations, was authentically more often isolated in the hospital than in the polyclinic (p<0.00001), whereas the bacteria of the phylogroup E, on the contrary, in the polyclinic (p<0.0001) . The hemolytic activity and biofilm-forming ability of UPEC strains did not differ in the two groups, while in the hospital hemolytic E. coli of the B2 phylogroup was significantly more likely than the polyclinic (p<0.001). In addition, B2 strainsformed biofilms in more than 60% cases. Regardless of the source of isolation, the strains were resistant to ampicillin (62.1%), amoxicillin/clavulanate (27.8%), cefotaxime (37.9%) and ciprofloxacin (36.9%). The production of ESBL was detected in fifty-one (25.8%) cultures, with a statistically significant difference in nosocomial strains: urinary

[The epidemiological microbiological characteristics of cultures of Candida albicans circulating in hospital for HIV-infected patients.]

The study was organized relating to 70 cultures of Candida albicans isolates from 19 patients (n=45) and from objects of hospital environment (n=25) in July 2013 and October2014 in specialized department for HIV-infected patients. The genetypical characteristic was given related to candida on the basis of polymerase chain reaction of intronic area of gene 25s pRNA and also their biological characteristics taking into account genotype. The rate of prevalence of Candida genotypes A, B, С and В made up to 58.6%, 10%, 18.6% and 12,8% correspondingly. It was established significant predominance of C.albicans genotype A in various commensal (pharynx) and transitory (skin) loci. In most cases, they were a cause of candidiasis, including invasive candidiasis. Besides, epresentatives of this group more frequently (85%) contaminated objects of hospital environment (p=0.0013). The cultures of C.albicans genotype В (Candida dubliniensis) were small in numbers and were isolated only from ecological biotypes of patients without clinic of candidiasis, were not detected in environment, were least active with exo-enzymes (phospholipase and protease) and were sensitive to tested anti-mycotic. In various biotops of single patients as a rule the only one strain persisted. In a number of cases genotypically different cultures were isolated. The residence of patient in hospital enhanced joining of C.albicans of other genotypes and in two cases were established a total change of cultures. Thus, in hospital environment of specialized hospitals can develop and long-time circulate hospital strains of C.albicans with high enzyme activity. The source are HIV-infected patients themselves that increases risk of of development of candidiasis.

Cell-Mediated Hemolytic Activity of Nosocomial Pseudomonas Aeruginosa Strains.

Cell-mediated hemolysis and adhesion index of nosocomial P. aeruginosa strains were experimentally studied. The highest hemoglobin release was recorded after centrifugation of erythrocyte and bacterial cell suspension preincubated at 37 C. All cultures were referred to highly adherent variants. The relationship between P. aeruginosa adhesion activity and erythrocyte lysis was found only in "passive" cell-cell contact. No correlation between cell-associated hemolysis and hemolysis caused by secreted factors was detected. It seems that the cytotoxicity of the studied P. aeruginosa strains was determined by ExoU and ExoS third type secretion effectors.

[The experience of implementation of REP-u RAPD-polymerase chain reaction in epidemiologic characteristic of nosocomial isolates Pseudomonas aeruginosa].

The article presents comparative evaluation of diagnostic value of technique REP- u RAPD-polymerase chain reaction applied under genetic typing of clinical isolates of Pseudomonas Aeruginosa. The strains are isolated in different hospital departments of medical institutions in adult (8 medical institutions; n = 145) and children (5 medical institutions; n = 151) medical networks. The results of study demonstrated different boundary capacity of three reactions. The Simpson discrimination index made up to 0.993, 0.875 and 0.639 for RAPD-, ERIC- and BOX-polymerase chain reaction correspondingly. The RAPD-polymerase chain reaction makes it possible to detect individual characteristics of strains. Out of two alternatives the REP-polymerase chain reaction demonstrated its advantage, besides only with one primer ERIC2. The BOX-polymerase chain reaction has a least discriminating capacity under typing of isolates P. aeruginosa, detecting only species' characteristics. The clinical strains P. aeruginosa are distributed on 24 genome groups and 52 isolates had individual genotypes. The evaluation of results of genetic typing permitted to point out both similarity of tendencies in propagation of strains of P. aeruginosa among hospitalized adults and adolescents and specificity of detection in neonatal clinics. It is obvious that hospitals of different profiles, including departments of reanimation and intensive therapy represent specific ecological environment significantly different in its level of endogenous and exogenous infection.

[Evaluation of biological properties of Pseudomonas aeruginosa strains isolated from patients with sternum and rib osteomyelitis].

AIM: Study of the role of P. aeruginosa in the development of osteomyelitis of sternum and ribs in cardio-surgery patients, and analysis of the main biological properties of the isolated bacterial strains. MATERIALS AND METHODS: 132 bacterial cultures were isolated from 83 hospital patients as a result of bacteriological examination during 2007-2013. Wound discharge was the study mate- rial. Sampling, seeding and identification of the isolated cultures was carried out by using the respective test-systems; antibiotic sensitivity was studied by disc-diffusion method. RESULTS: The proportion of P. aeruginosa was 10.6% (n = 14) that is comparable with data on wound infections of general surgery hospitals. A direct and strong correlation (R = 0.846, p = 0.000132) between hemolytic and phospholipase activity was established during evaluation of virulence properties of the isolated-strains. The degree of film-forming ability varied significantly from 0.122 to 1.412 OD; 64.3% ofthe studied cultures were highly film-forming variants. Statistically significant association between biofilm formation and other studied properties was not found. 4 strains produced VIM2-type metallo-betalactamase and had identical RAPD profiles. CONCLUSION: Considering that earlier the similar cultures were not detected and all of them were isolated at a short interval of time, we have made a conclusion, that their short-term circulation is probably associated with introduction, which was the reason for patient infection. P. aeruginosa could be the etio-pathogen of both early and later complications of cardio-surgical interventions.

[THE IMPORTANCE OF STRESS-ECHOCARDIOGRAPHY FOR DIFFERENTIAL DIAGNOSTICS OF APNEA IN PATIENTS WITH PERMANENT ELECTROCARDIOSTIMULATION].

UNLABELLED: Differential diagnostics of apnea regarded as an equivalent to angina or a manifestation of cardiac failure in patients with permanent electrocardiostimulation (PECS) encounters difficulties. Stress-EchoCG is the most adequate method of programmed high-frequency cardiac stimulation with the implanted pacemaker (PM) for excluding stress-induced myocardial ischemia in patients undergoing continuous stimulation of the right ventricle. The aim of the study was to assess the effectiveness and safety of stress-EchoCG by means of programmed high-frequency cardiac stimulation with the implanted PM for patients with single-chamber PECS and complaints of apnea. MATERIALS AND METHODS: The study included patients with single-chamber PECS in the VVIR mode (rate-responsive pacing), complaints of apnea under physical load, and suspected coronary heart disease. All of them underwent stress-EchoCG by means of programmed high-frequency cardiac pacing with the implanted PM. Positive results of the test served as indications for coronary angiography (CAG). RESULTS: The study included 31 patients. In 24 (77.4%) of them with a pacing rate of 90-120/min disturbances of left ventricular local contractility were induced. 18 patients underwent CAG. 15 (83%) of them had normal coronary arteries while 3 (17%) suffered hemodynamically significant stenosis. In other words, 3 patients presented with angina, in the remaining ones apnea was regarded as a manifestation of heart failure. CONCLUSION: In patients undergoing permanent stimulation of the right ventricle, stress-induced disturbances of left ventricular local contractility may be attributed to constrictive lesions of coronary arteries on the one hand and impaired myocardial perfusion due to disordered physiological sequence of cardiac stimulation on the other hand. Coronary atherosclerosis in patients with positive results of stress-EchoCG needs to be confirmed by CAG.

[Influence of Chlorhexidine and Prontosan on Dual Species and Monospecies Biofilms Formed by Staphylococcus aureus and Pseudomonas aeruginosa].

The effect of two antiseptics, i. e. chlorhexidine bigluconate 0.5% solution and Prontosan on dual species and monospecies biofilms formed in vitro by the reference strains P. aeruginosa ATCC 27853 and S. aureus ATCC 29213 was examined. It was demonstrated by atomic force microscopy that under the biocide action there occurred phenotype changes of the structural organization of the bacterial biofilms and morphology of the sessile cells: the cocci were lesser in diameter and the rods were reduced. A reliable change of linear cell sizes was accompanied by increase of their roughness (Sq) that was more pronounced for Prontosan. When assessing the cell viability it was found that Prontosan inhibited the bacterial viability in mixed and monospecies biofilms formed on both hydrophilic and hydrophobic abiotic surfaces. In the latter case the biofilm biomass (determined by crystal violet assay) lowered in all the variants of the experiment.

[Prevalence of cytotoxicity effectors in nosocomial Pseudomonas Aeruginosa strains].

AIM: Analysis of occurrence of the third type secretory system (TTSS) effectors in clinical P. aeruginosa strains. MATERIALS AND METHODS: Intra-hospital (n = 164) and extra-hospital (n = 30) strains of P. aeruginosa were studied. Detection of exoS and exoU genes was carried out by PCR in DNA Engine Dyad Thermal Cycler ("Bio-Rad", USA). Metallo-beta-lactamase (MBL) producers were detected by the presence of blaVIM-2 gene. RESULTS: Screening of intra- and extra-hospital strains for the presence of genes coding ExoS and ExoU showed, that exoS is detected in genome of clinical isolates in 59.8% and exoU--31.1% of cases. At the same time, strains with exoS-/exoU+ genotype predominated in lCU (Φ = 0.466; p = 0.0000). A significant association between the presence of the respective effectors and material of strain isolation was not detected. exoU gene was more frequently detected in genome of MBL producers (Φ = 0.784; p = 0.0004). CONCLUSION: A significant association between exoU and blaVIM-2 could be explained by clonal prevalence of P. aeruginosa ST235 VIM-2, circulation of those is noted on all the territory of Russia. As a rule, ExoU is produced by highly virulent poly-antibiotic resistant hospital isolates that determine unfavorable outcomes of pseudomonas infection.

[The experience of applying techniques of molecular genetics in identification of clinical strains Pseudomonas aeruginosa].

The article presents comparative analysis of application of common bacteriologic and molecular techniques to identify P. aerugenosa. The genetic detection was applied using polymerase chain reaction with genus-specific and species-specific primers and amplification of conservative sites of gens 16S pRNA with successive identification of bacteria by sequenation. It is established that 95% (151) of strains correspond to species of P. aerugenosa detected in primary bacteriologic laboratories and only 8 strains were not blue pus bacillus. Most of strains were closely congenial species: 2 isolates belonged to Pseudomonas aeruginosa group, 3 isolates to Pseudomonas putida group, 2 strains to Comamonas species and 1 isolate to Stenotrophomonas maltophilia species. The effectiveness of cultural technique of laboratory diagnostic was demonstrated concerning infections conditioned by P. aerugenosa. This conclusion does not eliminate application of molecular genetic trechnologies in complicated arbitral cases of bacteriologic analysis during monitoring of nosocomial infections.

[Phylogeography of red deer (Cervus elaphus): data of analysis of polymorphism of the mitochondrial gene for cytochrome b].

Analysis of polymorphism of the gene for cytochrome b (1140 bp) of 106 samples of red deer (Cervus elaphus) of Eurasia is carried out, and the phylogenetic relationships of groups throughout the entire geographic range, including North America, are reconstructed. In total, the paper describes 75 haplotypes, 33 of them for the European and 42 for the Asian part of the geographic range. Common haplotypes for these two parts of the range were not found. The genetic kinship of Asian Siberian stags and North American wapiti is confirmed. Red deer living in Yakutia are close to the Siberian stags of Altai and Tuva, whereas red deer that live in Krasnoyarsk krai and Irkutsk oblast form a separate group. Overall, the reconstructed phylogeographic structure of the species is significantly different from the accepted subspecies differentiation based on morphological characters.

[Effect of Pseudomonas aeruginosa exometabolites on planktonic and biofilm cultures of Escherichia coli].

AIM: Study the effect of P. aeruginosa exometabolites on planktonic and biofilm cultures of bioluminescent E. coli strain. MATERIALS AND METHODS: E. coli K12 TG1 (pF1 lux+ Ap(r)) recombinant bioluminescent strain, P. aeruginosa ATCC 27853 reference strain and 2 nosocomial isolates were used. Pyocyanin and pyoverdin content in supernatant of P. aeruginosa over-night cultures was evaluated according to E. Deziel et al. (2001). Planktonic and biofilm cultures of E. coli were obtained in 96-well plates (LB, statically, 37 degrees C), optical density of plankton, film biomass (OD600, OD580) and bioluminescence in plankton and biofilm were evaluated in microplate reader Infiniti M200 (Tecan, Austria). RESULTS: P. aeruginosa exometabolites increased the duration of lag-phase in E. coli, and short term exposition inhibited luminescence of planktonic cells. These effects are determined by bactericidal action ofpyocyanin and pyoverdin. Supernatants ofover-night cultures of P. aeruginosa inhibit formation of biofilm and disrupt the formed biofilm of E. coli. Effect of pyocyanin and pyoverdin on these processes is not established, other factors may have higher significance. CONCLUSION: Bioluminescence of E. coli K12 TGI that reflects the energetic status of the cell allows to evaluate and prognose the character of coexistence of P. aeruginosa in combined with E. coli planktonic and biofilm culture.