The increasing resistance in agents of nosocomial infections is one of the main problems of current medicine. The efficient treatment is also complicated by their ability to form biofilm. One of perspective alternatives to the treatment of these infections is the use of bacteriophages. The project is focused on the isolation of new phages and their subtypes effective against multiresistant strains of staphylococci and pseudomonades. Phages will be biologically and genetically characterized, including complete genome sequence. Capillary electrophoresis methods will be employed for the detection of phages in cultures. The lytic effect of the virulent phages as well as the synergistic effect of bacteriophages with antimicrobials will be assessed on nosocomial isolates. Within the analysis of tested phages and their ability to induce infections in bacteria persisting intracellulary in macrophages and bacteria growing in biofilm, the optimal therapeutic strategy for the treatment of chronic infections caused by intracellular-living and/or biofilm-forming bacteria will be proposed.

Rostoucí výskyt rezistencí u původců nozokomiálních infekcí je jedním z hlavních problémů současné medicíny. Úspěšnou léčbu dále komplikuje schopnost těchto bakterií růst ve formě biofilmu. Mezi perspektivní alternativy léčby takových infekcí patří využití bakteriofágů. V rámci projektu budou izolovány nové fágy či jejich subtypy účinné vůči nozokomiálním kmenům stafylokoků a pseudomonád. Fágy budou podrobně charakterizovány z hlediska jejich biologických a genetických vlastností, včetně kompletní sekvence genomu. Pomocí metod kapilární elektroforézy bude ověřena možnost jejich kvantifikace ve vzorku pro účely kontroly kvality fágové kultury. Účinky těchto fágů či jejich synergické kombinace s antimikrobiálními látkami budou ověřovány na nozokomiálních izolátech, zejm. na multirezistentních kmenech. Na základě analýzy schopnosti testovaných fágů infikovat bakterie perzistující uvnitř makrofágů a bakterie rostoucí ve formě biofilmu bude navržena optimální terapeutická strategie pro léčbu chronických infekcí spojených s intracelulárním přežíváním bakterií či s tvorbou biofilmu.

• MeSH
• antiinfekční látky terapeutické užití   MeSH
• biofilmy účinky léků   MeSH
• elektroforéza MeSH
• fágová terapie metody   MeSH
• infekce spojené se zdravotní péčí terapie   MeSH
• lidé MeSH
• mnohočetná bakteriální léková rezistence účinky léků   MeSH
• Pseudomonas aeruginosa izolace a purifikace   MeSH
• Staphylococcus aureus izolace a purifikace   MeSH
• Check Tag
• lidé MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• infekční lékařství
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

A taxonomic study was carried out on four Gram-stain-negative strains P5773T, P6169, P4708 and P6245, isolated from anus or mouth samples of Weddell seals at James Ross Island, Antarctica. The results of initial 16S rRNA gene sequence analysis showed that all four strains formed a group placed in the genus Pseudomonas and found Pseudomonas guineae and Pseudomonas peli to be their closest neighbours with 99.9 and 99.2 % sequence similarity, respectively. Sequence analysis of rpoD, rpoB and gyrB housekeeping genes confirmed the highest similarity of isolates to P. peli (rpoD) and to P. guineae (rpoB and gyrB). The average nucleotide identity value below 86 %, as calculated from the whole-genome sequence data, showed the low genomic relatedness of P5773T to its phylogenetic neighbours. The complete genome of strain P5773T was 4.4 Mb long and contained genes encoding proteins with biotechnological potential. The major fatty acids of the seal isolates were summed feature 8 (C18 : 1ω7c), summed feature 3 (C16 : 1ω7c/C16 : 1ω6c) and C16:0. The major respiratory quinone was Q9. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Putrescine and spermidine are predominant in the polyamine pattern. Further characterization performed using repetitive sequence-based PCR fingerprinting and MALDI-TOF MS analysis showed that the studied isolates formed a coherent cluster separated from the remaining Pseudomonas species and confirmed that they represent a novel species within the genus Pseudomonas, for which the name Pseudomonasleptonychotis sp. nov. is suggested. The type strain is P5773T (=CCM 8849T=LMG 30618T).

• MeSH
• bakteriální geny MeSH
• DNA bakterií genetika   MeSH
• fosfolipidy chemie   MeSH
• fylogeneze * MeSH
• mastné kyseliny chemie   MeSH
• Pseudomonas klasifikace   MeSH
• RNA ribozomální 16S genetika   MeSH
• sekvenční analýza DNA MeSH
• techniky typizace bakterií MeSH
• tuleňovití mikrobiologie   MeSH
• ubichinon chemie   MeSH
• zastoupení bazí MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Antarktida MeSH

This study presents a timely, reliable, and sensitive method for identification of pathogenic bacteria in clinical samples based on a combination of capillary electrophoresis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. In this respect, a part of a single-piece fused silica capillary was etched with supercritical water with the aim of using it for static or dynamic cell-surface adhesion from tens of microliter sample volumes. The conditions for this procedure were optimized. Adhered cells of Staphylococcus aureus (methicillin-susceptible or methicillin-resistant) and of Pseudomonas aeruginosa were desorbed and preconcentrated from the rough part of the capillary surface using transient isotachophoretic stacking from a high conductivity model matrix. The charged cells were swep and separated again in micellar electrokinetic chromatography using a nonionogenic surfactant. Static adhesion of the cells onto the roughened part of the capillary is certainly volumetric limited. Dynamic adhesion allows the concentration of bacteria from 100 μL volumes of physiological saline solution, bovine serum, or human blood with the limits of detection at 1.8 × 102, 1.7 × 103, and 1.0 × 103 cells mL-1, respectively. The limits of detection were the same for all three examined bacterial strains. The recovery of the method was about 83% and it was independent of the sample matrix. A combination of capillary electrophoresis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry required at least 4 × 103 cells mL-1 to obtain reliable results. The calibration plots were linear (R2 = 0.99) and the relative standard deviations of the peak area were at most 2.2%. The adhered bacteria, either individual or in a mixture, were online analyzed by micellar electrokinetic chromatography and then collected from the capillary and off-line analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry without interfering matrix components.

• MeSH
• Bacteria izolace a purifikace   MeSH
• bakteriální adheze MeSH
• bakteriologické techniky MeSH
• elektroforéza kapilární metody   MeSH
• koncentrace vodíkových iontů MeSH
• micely MeSH
• oxid křemičitý chemie   MeSH
• Pseudomonas aeruginosa izolace a purifikace   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   MeSH
• Staphylococcus aureus izolace a purifikace   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Bacteriophages of the significant veterinary pathogen Staphylococcus pseudintermedius are rarely described morphologically and genomically in detail, and mostly include phages of the Siphoviridae family. There is currently no taxonomical classification for phages of this bacterial species. Here we describe a new phage designated vB_SpsS_QT1, which is related to phage 2638A originally described as a Staphylococcus aureus phage. Propagating strain S. aureus 2854 of the latter was reclassified by rpoB gene sequencing as S. pseudintermedius 2854 in this work. Both phages have a narrow but different host range determined on 54 strains. Morphologically, both of them belong to the family Siphoviridae, share the B1 morphotype, and differ from other staphylococcal phage genera by a single long fibre at the terminus of the tail. The complete genome of phage vB_SpsS_QT1 was sequenced with the IonTorrent platform and expertly annotated. Its linear genome with cohesive ends is 43,029 bp long and encodes 60 predicted genes with the typical modular structure of staphylococcal siphophages. A global alignment found the genomes of vB_SpsS_QT1 and 2638A to share 84% nucleotide identity, but they have no significant similarity of nucleotide sequences with other phage genomes available in public databases. Based on the morphological, phylogenetic, and genomic analyses, a novel genus Fibralongavirus in the family Siphoviridae is described with phage species vB_SpsS_QT1 and 2638A.

• MeSH
• fylogeneze MeSH
• genom virový MeSH
• genomika metody   MeSH
• hostitelská specificita MeSH
• replikace viru MeSH
• Siphoviridae klasifikace   ultrastruktura   MeSH
• Staphylococcus virologie   MeSH
• virion ultrastruktura   MeSH
• virové geny MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Phages infecting Staphylococcus aureus can be used as therapeutics against antibiotic-resistant bacterial infections. However, there is limited information about the mechanism of genome delivery of phages that infect Gram-positive bacteria. Here, we present the structures of native S. aureus phage P68, genome ejection intermediate, and empty particle. The P68 head contains 72 subunits of inner core protein, 15 of which bind to and alter the structure of adjacent major capsid proteins and thus specify attachment sites for head fibers. Unlike in the previously studied phages, the head fibers of P68 enable its virion to position itself at the cell surface for genome delivery. The unique interaction of one end of P68 DNA with one of the 12 portal protein subunits is disrupted before the genome ejection. The inner core proteins are released together with the DNA and enable the translocation of phage genome across the bacterial membrane into the cytoplasm.

• MeSH
• bakteriofágy genetika   MeSH
• buněčná membrána genetika   MeSH
• cytoplazma genetika   MeSH
• DNA virů genetika   MeSH
• genom virový genetika   MeSH
• Staphylococcus aureus genetika   MeSH
• virion genetika   MeSH
• virové plášťové proteiny genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cellulose-based preparative isoelectric focusing was used for preseparation and concentration of uropathogens Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Staphylococcus epidermidis, Candida albicans, and Candida parapsilosis in a urine sample containing a high concentration of human serum albumin. For the visibility of the colorless microbial zones in the separation medium, the microbial cells were labeled with red nonionogenic tenside (1-[[4-(phenylazo)phenyl]azo]-2-hydroxy-3-naphthoic acid polyethylene glycol ester, PAPAN). A very short incubation time, about 2 min, was sufficient for the adsorption of 0.001% (w/v) PAPAN onto the cell surface at the optimized conditions. As low as 103 cells of E. coli (pI 4.6) resuspended in 100 μL of urine sample and spiked with 0.1 mg mL-1 of human serum albumin (pI 4.8) were successfully preseparated and concentrated using this method. Because the pI values of the labeled microorganisms remained unchanged, the focused red zones of microbial cells were collected from the separation media and further analyzed by either capillary isoelectric focusing or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The viability of the cells extracted from the collected zones was also confirmed. The proposed method provides reliable, relatively fast, and cost-effective identification of uropathogens in urine specimens with a high level of albumin.

• MeSH
• Bacteria klasifikace   izolace a purifikace   MeSH
• barvení a značení metody   MeSH
• houby klasifikace   izolace a purifikace   MeSH
• infekce močového ústrojí mikrobiologie   MeSH
• isoelektrická fokusace MeSH
• lidé MeSH
• lidský sérový albumin analýza   MeSH
• povrchově aktivní látky chemie   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Staphylococcus aureus may be a highly virulent human pathogen, especially when it is able to form a biofilm, and it is resistant to antibiotic. Infections caused by these bacteria significantly affect morbidity and mortality, primarily in hospitalized patients. Treatment becomes more expensive, more toxic, and prolonged. This is the reason why research on alternative therapies should be one of the main priorities of medicine and biotechnology. A promising alternative treatment approach is bacteriophage therapy. The effect of the anti-staphylococcal bacteriophage preparation Stafal® on biofilm reduction was assessed on nine S. aureus strains using both sonication with subsequent quantification of surviving cells on the catheter surface and evaluation of biofilm reduction in microtiter plates. It was demonstrated that the bacteriophages destroy planktonic cells very effectively. However, to destroy cells embedded in the biofilm effectively requires a concentration at least ten times higher than that provided by the commercial preparation. The catheter disc method (CDM) allowed easier comparison of the effect on planktonic cells and cells in a biofilm than the microtiter plate (MTP) method.

• MeSH
• antiinfekční látky * MeSH
• bakteriologické techniky MeSH
• biofilmy * MeSH
• lidé MeSH
• methicilin rezistentní Staphylococcus aureus růst a vývoj   izolace a purifikace   virologie   MeSH
• mikrobiální viabilita MeSH
• počet mikrobiálních kolonií MeSH
• stafylokokové bakteriofágy fyziologie   MeSH
• stafylokokové infekce mikrobiologie   MeSH
• Staphylococcus aureus růst a vývoj   izolace a purifikace   virologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Aim: Finding rapid, reliable diagnostic methods is a big challenge in clinical microbiology. Raman spectroscopy is an optical method used for multiple applications in scientific fields including microbiology. This work reports its potential in identifying biofilm positive strains of Candida parapsilosis and Staphylococcus epidermidis. Materials & methods: We tested 54 S. epidermidis strains (23 biofilm positive, 31 negative) and 51 C. parapsilosis strains (27 biofilm positive, 24 negative) from colonies on Mueller-Hinton agar plates, using Raman spectroscopy. Results: The accuracy was 98.9% for C. parapsilosis and 96.1% for S. epidermidis. Conclusion: The method showed great potential for identifying biofilm positive bacterial and yeast strains. We suggest that Raman spectroscopy might become a useful aid in clinical diagnostics.

• MeSH
• biofilmy růst a vývoj   MeSH
• Candida parapsilosis metabolismus   MeSH
• diagnostické testy rutinní metody   MeSH
• lidé MeSH
• Ramanova spektroskopie metody   MeSH
• Staphylococcus epidermidis metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Lytic bacteriophages are valuable therapeutic agents against bacterial infections. There is continual effort to obtain new phages to increase the effectivity of phage preparations against emerging phage-resistant strains. Here we described the genomic diversity of spontaneous host-range mutants of kayvirus 812. Five mutant phages were isolated as rare plaques on phage-resistant Staphylococcus aureus strains. The host range of phage 812-derived mutants was 42% higher than the wild type, determined on a set of 186 methicillin-resistant S. aureus strains representing the globally circulating human and livestock-associated clones. Comparative genomics revealed that single-nucleotide polymorphisms from the parental phage 812 population were fixed in next-step mutants, mostly in genes for tail and baseplate components, and the acquired point mutations led to diverse receptor binding proteins in the phage mutants. Numerous genome changes associated with rearrangements between direct repeat motifs or intron loss were found. Alterations occurred in host-takeover and terminal genomic regions or the endolysin gene of mutants that exhibited the highest lytic activity, which implied various mechanisms of overcoming bacterial resistance. The genomic data revealed that Kayvirus spontaneous mutants are free from undesirable genes and their lytic properties proved their suitability for rapidly updating phage therapeutics.

• MeSH
• bakteriální léková rezistence MeSH
• bakteriofágy genetika   MeSH
• délka genomu MeSH
• genom virový MeSH
• genomika MeSH
• jednonukleotidový polymorfismus MeSH
• methicilin farmakologie   MeSH
• mutace * MeSH
• Staphylococcus aureus růst a vývoj   virologie   MeSH
• zastoupení bazí MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Amphotericin B (AmB) is still, despite its severe nephrotoxicity, the first-line agent in the management of serious systemic fungal infections. A sensitive and reliable method is therefore required to control AmB concentration in body fluids of a patient. This study demonstrates the potential of the off-line combination of preparative isoelectric focusing (IEF) with capillary isoelectric focusing (CIEF) or capillary zone electrophoresis (CZE) in the determination of AmB in human blood serum. The required value of the isoelectric point of AmB was determined to be 6.1 using the CIEF technique. Preparative IEF served as a pre-separation and concentration technique. The pH gradient was traced by colored low molecular pI markers. The collected fraction with AmB was easily processed and then analyzed by CIEF and CZE. Tens of picograms of AmB in human blood serum sample can be determined by a combination of preparative IEF with CZE. The method was linear in the AmB concentration range of 0.3-600ngmL-1. The recovery ranged from 93% to 98%. Copyright © 2018 Elsevier B.V. All rights reserved.

• MeSH
• amfotericin B * izolace a purifikace   krev   MeSH
• biochemická analýza krve * metody   MeSH
• elektroforéza kapilární * metody   MeSH
• isoelektrická fokusace MeSH
• lidé MeSH
• limita detekce * MeSH
• Check Tag
• lidé MeSH