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1.
Sci Rep ; 14(1): 9088, 2024 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643290

RESUMO

The emerging antibiotic resistance in pathogenic bacteria is a key problem in modern medicine that has led to a search for novel therapeutic strategies. A potential approach for managing such bacteria involves the use of their natural killers, namely lytic bacteriophages. Another effective method involves the use of metal nanoparticles with antimicrobial properties. However, the use of lytic phages armed with nanoparticles as an effective antimicrobial strategy, particularly with respect to biofilms, remains unexplored. Here, we show that T7 phages armed with silver nanoparticles exhibit greater efficacy in terms of controlling bacterial biofilm, compared with phages or nanoparticles alone. We initially identified a novel silver nanoparticle-binding peptide, then constructed T7 phages that successfully displayed the peptide on the outer surface of the viral head. These recombinant, AgNP-binding phages could effectively eradicate bacterial biofilm, even when used at low concentrations. Additionally, when used at concentrations that could eradicate bacterial biofilm, T7 phages armed with silver nanoparticles were not toxic to eukaryotic cells. Our results show that the novel combination of lytic phages with phage-bound silver nanoparticles is an effective, synergistic and safe strategy for the treatment of bacterial biofilms.


Assuntos
Bacteriófagos , Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Bactérias , Bacteriófago T7 , Biofilmes , Peptídeos
2.
Int J Nanomedicine ; 18: 6449-6467, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026518

RESUMO

Introduction: Hybrid nanoflowers are structures consisting of organic (enzymes, proteins, nucleic acids) and inorganic components (mostly metal phosphates) with a flower-like hierarchical structure. Novel hybrid nanoflowers based on bovine serum albumin (BSA) and hydroxyapatite (HA) were obtained and characterized. Study on BSA-HA nanoflowers as potential drug delivery system is reported for the first time. Methods: Embedding ciprofloxacin in the structure of hybrid nanoflowers was confirmed by ATR-FTIR and thermogravimetric analysis. The inorganic phase of the nanoflowers was determined by X-ray diffraction. UV‒Vis spectroscopy was used to evaluate the release profiles of ciprofloxacin from nanoflowers in buffer solutions at pH 7.4 and 5. The agar disk diffusion method was used to study the antibacterial activity of the synthesized nanoflowers against Staphylococcus aureus and Pseudomonas aeruginosa. Results: Bovine serum albumin - hydroxyapatite nanoflowers were obtained with diameters of ca. 1-2 µm. The kinetics of ciprofloxacin release from nanoflowers were described by the Korsmeyer-Peppas model. The antibacterial activity of the synthesized nanoflowers was demonstrated against S. aureus and P. aeruginosa, two main pathogens found in osteomyelitis. Conclusion: The formulated nanoflowers may act as an efficient local antibiotic delivery system. Due to the use of nonhazardous, biodegradable components and benign synthesis, hybrid nanoflowers are very promising drug delivery systems that could be applied in the treatment of skeletal system infections.


Assuntos
Ciprofloxacina , Soroalbumina Bovina , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Staphylococcus aureus , Durapatita/química , Sistemas de Liberação de Medicamentos , Antibacterianos/farmacologia , Antibacterianos/química
3.
Crit Rev Microbiol ; : 1-16, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897236

RESUMO

Bacteriophages are the most numerous entities on earth and are found everywhere their bacterial hosts live. As natural bacteria killers, phages are extensively investigated as a potential cure for bacterial infections. Neisseria gonorrhoeae (the gonococcus) is the etiologic agent of a sexually transmitted disease: gonorrhea. The rapid increase of resistance of N. gonorrhoeae to antibiotics urges scientists to look for alternative treatments to combat gonococcal infections. Phage therapy has not been tested as an anti-gonococcal therapy so far. To date, no lytic phage has been discovered against N. gonorrhoeae. Nevertheless, gonococcal genomes contain both dsDNA and ssDNA prophages, and viral particle induction has been documented. In this review, we consider literature data about the attempts of hunting for a bacteriophage specific for gonococci - the gonophage. We also discuss the potential application of prophage elements in the fight against N. gonorrhoeae. Temperate phages may be useful in preventing and treating gonorrhea as a scaffold for anti-gonococcal vaccine development and as a source of lytic enzymes with anti-gonococcal activity.

4.
Sci Rep ; 13(1): 7960, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198390

RESUMO

Balneotherapy is an effective treatment method in various diseases and commonly used treatment modality among patients with musculoskeletal disorders. Sulfur baths are known for healing properties however effect on rheological properties is unstudied. Thus the aim of our study was to determine the effect of sulfur balneotherapy on hemorheological blood indices. A total of 48 patients with osteoarthritis were enrolled to the study. Blood samples were collected twice, before and after 3-week time period. We evaluated complete blood count, fibrinogen, hs-CRP and blood rheology parameters such as elongation index (EI), half-time of total aggregation (T1/2) and aggregation index (AI) analyzed with the Lorrca Maxis. Mean age of studied cohort was 67 ± 5 years. After sulfur baths WBC count was significantly decreased is studied group (p = 0.021) as well as neutrophile count (p = 0.036). Red blood cell EIs were statistically higher after sulfur baths in shear stress ranging from 8.24 to 60.30 Pa. T1/2 was significantly higher (p = 0.031) and AI lower (p = 0.003) compared to baseline. No significant changes in fibrinogen and hs-CRP were observed. It is the first study that evaluate effect of sulfur balneotherapy on rheologic properties of blood. Sulfur water baths may improve erythrocyte deformability and aggregation parameters.


Assuntos
Hemorreologia , Osteoartrite , Humanos , Pessoa de Meia-Idade , Idoso , Banhos , Proteína C-Reativa/farmacologia , Deformação Eritrocítica , Viscosidade Sanguínea , Osteoartrite/terapia , Fibrinogênio/análise , Enxofre/farmacologia , Agregação Eritrocítica
5.
Artigo em Inglês | MEDLINE | ID: mdl-36674407

RESUMO

Background: There is still an ongoing debate about the role of the craniomandibular system, including occlusal conditions, on postural stability. This study aims to assess the role of antero-posterior malocclusion on postural control and plantar pressure distribution during standing and walking. Methods: 90 healthy volunteers (aged 19 to 35) were qualified for the study. The subjects were assigned to three groups, depending on the occlusion type. Each group (Angle Class I, II and III) consisted of 30 people. The research procedure included a clinical occlusal assessment performed by a dentist. Postural control measurements were carried out using a force platform by measuring plantar pressure distribution during standing (six trials with and without visual control) and walking test conditions. Results: The tendency to shift the CoP forward is demonstrated by Angle Class II subjects and backwards by Class I and III subjects (p < 0.001). Individuals with a malocclusion demonstrated significantly higher selected stabilographic parameters while standing on both feet (with eyes open and closed) and during the single-leg test with eyes open (p < 0.05). The analysis of the dynamic test results showed no significant correlations between Angle Classes and the selected gait parameters. Conclusions: Analyses conducted among individuals with malocclusions showed the impact of occlusion on static postural stability. In order to diagnose and effectively treat malocclusion, a multidisciplinary approach with the participation of dentists and physiotherapy specialists is necessary, with the use of stabilometric and kinematic posture assessments.


Assuntos
Oclusão Dentária , Má Oclusão , Humanos , Adulto , Marcha , Postura , Posição Ortostática , Equilíbrio Postural
6.
Sci Total Environ ; 856(Pt 2): 159072, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36179845

RESUMO

Arctic soils are constantly subjected to extreme environmental conditions such as low humidity, strong winds, high salinity, freeze-thaw cycles, UV exposition, and low nutrient availability, therefore, they have developed unique microbial ecosystems. These environments provide excellent opportunities to study microbial ecology and evolution within pristine (i.e. with limited anthropogenic influence) regions since the High Arctic is still considered one of the wildest and least explored environments on the planet. This environment is also of interest for the screening and recovery of unique microbial strains suitable for various biotechnological applications. In this study, a combination of culture-depended and culture-independent approaches was used to determine the cultivation bias in studies of the diversity of cold-active microorganisms. Cultivation bias is a reduction in recovered diversity, introduced when applying a classical culturing technique. Six different soil types, collected in the vicinity of the Polish Polar Station Hornsund (Spitsbergen, Norway), were tested. It was revealed that the used media allowed recovery of only 6.37 % of bacterial and 20 % of fungal genera when compared with a culture-independent approach. Moreover, it was shown that a combination of R2A and Marine Broth media recovered as much as 93.6 % of all cultivable bacterial genera detected in this study. Based on these results, a novel protocol for genome-guided bioprospecting, combining a culture-dependent approach, metabarcoding, next-generation sequencing, and genomic data reuse was developed. With this methodology, 14 psychrotolerant, multi-metal-resistant strains, including the highly promising Rhodococcus spp., were obtained. These strains, besides increased metal tolerance, have a petroleum hydrocarbon utilization capacity, and thus may be good candidates for future bioremediation technologies, also suited to permanently cold regions.


Assuntos
Bioprospecção , Pergelissolo , Microbiologia do Solo , Ecossistema , Biodiversidade , Svalbard , Bactérias/genética , Solo , Fungos/genética , Regiões Árticas
7.
Microorganisms ; 10(2)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35208677

RESUMO

Caves have been an item of amateur and professional exploration for many years. Research on the karst caves has revealed great diversity of bacteria, algae, and fungi living on stone walls and speleothems, in mud puddles or sediments. They have become the source of interest for various research groups including geologists, chemists, ecologists, or microbiologists. The adaptations of cave-dwelling organisms applied to their survival are complex and some of their properties show potential to be used in various areas of human life. Secondary metabolites produced by cave's bacteria show strong antimicrobial, anti-inflammatory, or anticancer properties. Furthermore, bacteria that can induce mineral precipitation could be used in the construction industry and for neutralization of radioisotopes. In this review we focus on bacteria and algae present in cave ecosystems, their role in shaping such specific environment, and their biotechnological and medical potential.

8.
Antibiotics (Basel) ; 10(10)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34680793

RESUMO

Resistance of bacteria, fungi and cancer cells to antibiotics and other drugs is recognized as one of the major problems in current medicine. Therefore, a search for new biologically active compounds able to either kill pathogenic cells or inhibit their growth is mandatory. Hard-to-reach habitats appear to be unexplored sources of microorganisms producing previously unknown antibiotics and other molecules revealing potentially therapeutic properties. Caves belong to such habitats, and Actinobacteria are a predominant group of microorganisms occurring there. This group of bacteria are known for production of many antibiotics and other bioactive compounds. Interestingly, it was demonstrated previously that infection with bacteriophages might enhance production of antibiotics by them. Here, we describe a series of newly isolated strains of Actinobacteria that were found in caves from the Tatra Mountains (Poland). Phage induction tests indicated that some of them may bear active prophages able to produce virions upon treatment with mitomycin C or UV irradiation. Among all the examined bacteria, two newly isolated Streptomyces sp. strains were further characterized to demonstrate their ability to inhibit the growth of pathogenic bacteria (strains of Staphylococcus aureus, Salmonella enterica, Enterococcus sp., Escherichia coli, and Pseudomonas aeruginosa) and fungi (different species and strains from the genus Candida). Moreover, extracts from these Streptomyces strains reduced viability of the breast-cancer cell line T47D. Chemical analyses of these extracts indicated the presence of isomers of dichloranthrabenzoxocinone and 4,10- or 10,12-dichloro-3-O-methylanthrabenzoxocinone, which are putative antimicrobial compounds. Moreover, various previously unknown (unclassified) molecules were also detected using liquid chromatography-mass spectrometry, suggesting that tested Streptomyces strains may synthesize a battery of bioactive compounds with antibacterial, antifungal, and anticancer activities. These results indicate that further studies on the newly isolated Actinobacteria might be a promising approach to develop novel antibacterial, antifungal, and/or anticancer drugs.

9.
Int J Mol Sci ; 21(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575645

RESUMO

Increasing multidrug resistance has led to renewed interest in phage-based therapy. A combination of the bacteriophages and antibiotics presents a promising approach enhancing the phage therapy effectiveness. First, phage candidates for therapy should be deeply characterized. Here we characterize the bacteriophage vB_AbaP_AGC01 that poses antibacterial activity against clinical Acinetobacter baumannii strains. Moreover, besides genomic and phenotypic analysis our study aims to analyze phage-antibiotic combination effectiveness with the use of ex vivo and in vivo models. The phage AGC01 efficiently adsorbs to A. baumannii cells and possesses a bacteriolytic lifecycle resulting in high production of progeny phages (317 ± 20 PFU × cell-1). The broad host range (50.27%, 93 out of 185 strains) against A. baumannii isolates and the inability of AGC01 to infect other bacterial species show its high specificity. Genomic analysis revealed a high similarity of the AGC01 genome sequence with that of the Friunavirus genus from a subfamily of Autographivirinae. The AGC01 is able to significantly reduce the A. baumannii cell count in a human heat-inactivated plasma blood model (HIP-B), both alone and in combination with antibiotics (gentamicin (GEN), ciprofloxacin (CIP), and meropenem (MER)). The synergistic action was observed when a combination of phage treatment with CIP or MER was used. The antimicrobial activity of AGC01 and phage-antibiotic combinations was confirmed using an in vivo larva model. This study shows the greatest increase in survival of G. mellonella larvae when the combination of phage (MOI = 1) and MER was used, which increased larval survival from 35% to 77%. Hence, AGC01 represents a novel candidate for phage therapy. Additionally, our study suggests that phages and antibiotics can act synergistically for greater antimicrobial effect when used as combination therapy.


Assuntos
Infecções por Acinetobacter/terapia , Acinetobacter baumannii/virologia , Antibacterianos/uso terapêutico , Bacteriófagos/fisiologia , Lepidópteros/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Animais , Antibacterianos/farmacologia , Bacteriólise , Bacteriófagos/classificação , Bacteriófagos/genética , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico , Terapia Combinada , Modelos Animais de Doenças , Genoma Viral , Temperatura Alta , Humanos , Meropeném/farmacologia , Meropeném/uso terapêutico , Terapia por Fagos , Fenótipo , Especificidade da Espécie , Sequenciamento Completo do Genoma
10.
Med Sci Monit ; 26: e921602, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32347218

RESUMO

BACKGROUND Treatment of displaced intra-articular calcaneal fractures is controversial. Choosing the optimal surgical technique is very important for patient quality of life and activity. In this study, we asked the question: "What is the long-term quality of life of patients after intra-articular calcaneal fractures treated by minimally invasive reduction and percutaneous stabilization (MIRPS)?". MATERIAL AND METHODS We included 51 patients - 45 males (88%) and 6 females (12%) - who underwent MIRPS of intra-articular calcaneal fractures. The males were ages 22-63 years, with a mean age of 46 years, while the females were aged 31-63, with a mean age of 47 years. The FAOS (Foot and Ankle Outcome Score) survey was used. RESULTS Women's FAOS scores were 72-95%, with a mean of 82%, and varied according to type of fracture, surgery method used, and comorbid fractures. Men's FAOS scores were 50-95%, with a mean of 84%, and varied according to type of fracture, surgery method used, and comorbid fractures. CONCLUSIONS According to set criteria regarding the FAOS scale, mainly good and very good results were observed in patients treated surgically for intra-articular calcaneus fractures using MIRPS. Westhues' method scored a significantly higher foot rating than W-R (Westhues'-Rapala method). Patients with TTF (tongue-type fracture) scored higher in the FAOS than patients treated with JDTF (joint depression-type fracture). In other cases, no significant differences were observed.


Assuntos
Calcâneo/cirurgia , Fraturas Intra-Articulares/terapia , Qualidade de Vida/psicologia , Adulto , Tornozelo/cirurgia , Feminino , Pé/cirurgia , Traumatismos do Pé/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento
11.
Int J Mol Sci ; 21(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197547

RESUMO

The Ochrobactrum genus consists of an extensive repertoire of biotechnologically valuable bacterial strains but also opportunistic pathogens. In our previous study, a novel strain, Ochrobactrum sp. POC9, which enhances biogas production in wastewater treatment plants (WWTPs) was identified and thoroughly characterized. Despite an insightful analysis of that bacterium, its susceptibility to bacteriophages present in WWTPs has not been evaluated. Using raw sewage sample from WWTP and applying the enrichment method, two virulent phages, vB_OspM_OC and vB_OspP_OH, which infect the POC9 strain, were isolated. These are the first virulent phages infecting Ochrobactrum spp. identified so far. Both phages were subjected to thorough functional and genomic analyses, which allowed classification of the vB_OspM_OC virus as a novel jumbo phage, with a genome size of over 227 kb. This phage encodes DNA methyltransferase, which mimics the specificity of cell cycle regulated CcrM methylase, a component of the epigenetic regulatory circuits in Alphaproteobacteria. In this study, an analysis of the overall diversity of Ochrobactrum-specific (pro)phages retrieved from databases and extracted in silico from bacterial genomes was also performed. Complex genome mining allowed us to build similarity networks to compare 281 Ochrobactrum-specific viruses. Analyses of the obtained networks revealed a high diversity of Ochrobactrum phages and their dissimilarity to the viruses infecting other bacteria.


Assuntos
Bacteriófagos/genética , Vírus de DNA/genética , Genoma Viral , Ochrobactrum/virologia , Ochrobactrum/genética
12.
Int J Mol Sci ; 21(4)2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32093105

RESUMO

Bordetella bronchiseptica, an emerging zoonotic pathogen, infects a broad range of mammalian hosts. B. bronchiseptica-associated atrophic rhinitis incurs substantial losses to the pig breeding industry. The true burden of human disease caused by B. bronchiseptica is unknown, but it has been postulated that some hypervirulent B. bronchiseptica isolates may be responsible for undiagnosed respiratory infections in humans. B. bronchiseptica was shown to acquire antibiotic resistance genes from other bacterial genera, especially Escherichia coli. Here, we present a new B. bronchiseptica lytic bacteriophage-vB_BbrP_BB8-of the Podoviridae family, which offers a safe alternative to antibiotic treatment of B. bronchiseptica infections. We explored the phage at the level of genome, physiology, morphology, and infection kinetics. Its therapeutic potential was investigated in biofilms and in an in vivo Galleria mellonella model, both of which mimic the natural environment of infection. The BB8 is a unique phage with a genome structure resembling that of T7-like phages. Its latent period is 75 ± 5 min and its burst size is 88 ± 10 phages. The BB8 infection causes complete lysis of B. bronchiseptica cultures irrespective of the MOI used. The phage efficiently removes bacterial biofilm and prevents the lethality induced by B. bronchiseptica in G. mellonella honeycomb moth larvae.


Assuntos
Infecções por Bordetella/veterinária , Bordetella bronchiseptica/patogenicidade , Bordetella bronchiseptica/virologia , Podoviridae/genética , Animais , Biofilmes , Infecções por Bordetella/terapia , Bordetella bronchiseptica/ultraestrutura , Interações entre Hospedeiro e Microrganismos , Concentração de Íons de Hidrogênio , Larva/microbiologia , Lepidópteros/microbiologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Filogenia , Podoviridae/crescimento & desenvolvimento , Podoviridae/efeitos da radiação , Podoviridae/ultraestrutura , Temperatura , Vírion/isolamento & purificação , Vírion/ultraestrutura
13.
Microbiol Resour Announc ; 8(29)2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320427

RESUMO

We present here the draft genome sequence of Paracoccus sp. strain 228, isolated from the Gulf of Gdansk in the southern part of the Baltic Sea. The assembly contains 4,131,609 bp in 32 scaffolds.

14.
Sci Rep ; 9(1): 7899, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133656

RESUMO

Bacteria of the genus Paracoccus inhabit various pristine and anthropologically-shaped environments. Many Paracoccus spp. have biotechnological value and several are opportunistic human pathogens. Despite extensive knowledge of their metabolic potential and genome architecture, little is known about viruses of Paracoccus spp. So far, only three active phages infecting these bacteria have been identified. In this study, 16 Paracoccus strains were screened for the presence of active temperate phages, which resulted in the identification of five novel viruses. Mitomycin C-induced prophages were isolated, visualized and their genomes sequenced and thoroughly analyzed, including functional validation of their toxin-antitoxin systems. This led to the identification of the first active Myoviridae phage in Paracoccus spp. and four novel Siphoviridae phages. In addition, another 53 prophages were distinguished in silico within genomic sequences of Paracoccus spp. available in public databases. Thus, the Paracoccus virome was defined as being composed of 66 (pro)phages. Comparative analyses revealed the diversity and mosaicism of the (pro)phage genomes. Moreover, similarity networking analysis highlighted the uniqueness of Paracoccus (pro)phages among known bacterial viruses.


Assuntos
Genoma Viral/genética , Myoviridae/isolamento & purificação , Paracoccus/virologia , Prófagos/isolamento & purificação , Siphoviridae/isolamento & purificação , Simulação por Computador , DNA Viral/genética , DNA Viral/isolamento & purificação , Genômica , Microscopia Eletrônica de Transmissão , Mitomicina/farmacologia , Anotação de Sequência Molecular , Mosaicismo , Myoviridae/genética , Myoviridae/ultraestrutura , Paracoccus/efeitos dos fármacos , Paracoccus/genética , Prófagos/efeitos dos fármacos , Prófagos/genética , Siphoviridae/genética , Siphoviridae/ultraestrutura
15.
Front Microbiol ; 9: 3144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619210

RESUMO

Arthrobacter spp. are coryneform Gram-positive aerobic bacteria, belonging to the class Actinobacteria. Representatives of this genus have mainly been isolated from soil, mud, sludge or sewage, and are usually mesophiles. In recent years, the presence of Arthrobacter spp. was also confirmed in various extreme, including permanently cold, environments. In this study, 36 psychrotolerant and metalotolerant Arthrobacter strains isolated from petroleum-contaminated soil from the King George Island (Antarctica), were screened for the presence of plasmids. The identified replicons were thoroughly characterized in order to assess their diversity and role in the adaptation of Arthrobacter spp. to harsh Antarctic conditions. The screening process identified 11 different plasmids, ranging in size from 8.4 to 90.6 kb. A thorough genomic analysis of these replicons detected the presence of numerous genes encoding proteins that potentially perform roles in adaptive processes such as (i) protection against ultraviolet (UV) radiation, (ii) resistance to heavy metals, (iii) transport and metabolism of organic compounds, (iv) sulfur metabolism, and (v) protection against exogenous DNA. Moreover, 10 of the plasmids carry genetic modules enabling conjugal transfer, which may facilitate their spread among bacteria in Antarctic soil. In addition, transposable elements were identified within the analyzed plasmids. Some of these elements carry passenger genes, which suggests that these replicons may be actively changing, and novel genetic modules of adaptive value could be acquired by transposition events. A comparative genomic analysis of plasmids identified in this study and other available Arthrobacter plasmids was performed. This showed only limited similarities between plasmids of Antarctic Arthrobacter strains and replicons of other, mostly mesophilic, isolates. This indicates that the plasmids identified in this study are novel and unique replicons. In addition, a thorough meta-analysis of 247 plasmids of psychrotolerant bacteria was performed, revealing the important role of these replicons in the adaptation of their hosts to extreme environments.

16.
Methods Mol Biol ; 1693: 219-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29119443

RESUMO

In a view of growing interest in bacteriophages as the most abundant members of microbial communities and as antibacterial agents, reliable methods for bacteriophage long-term preservation, that warrant the access to original or mutant stocks of unchanged properties, have become of crucial importance. A storage method that retains the infectivity of any kind of bacteriophage virions, either in a cell lysate or in a purified suspension, does not exist, due to the enormous diversity of bacteriophages and hence the differentiation of their sensitivity to various storage conditions. Here, we describe a method of long-term bacteriophage preservation, which is based on freezing of freshly infected susceptible bacteria at early stages of bacteriophage development. The infected bacteria release mature bacteriophages upon melting enabling the recovery of bacteriophage virions with high efficiency. The only limitation of this method is the sensitivity of bacteriophage host to deep-freezing, and thus it can be used for the long-term preservation of the vast majority of bacteriophages.


Assuntos
Bactérias/virologia , Bacteriófagos/fisiologia , Preservação Biológica/métodos , Vírion/fisiologia
17.
Folia Med Cracov ; 57(3): 15-28, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29263451

RESUMO

The choice of method for surgical treatment of articular calcaneal fractures remains problematic due to the potential complications and difficulty in restoring loss of functional status, anatomical geometry and congruence of joint surfaces. The preferred method of surgical treatment for these injuries, among others, is still minimally invasive percutaneous fixation. The aim of this study was to evaluate the radiological results of articular calcaneal fractures surgical treatment using a minimally invasive percutaneous fixation and to determine the prevalence of complications in early and long-term observation. Radiological results of surgical treatment of 82 patients operated using minimally invasive percutaneous fixation were analyzed. The radiological results were based on Bohler angle and varus angle using criteria according to Harnroongroj and Golec. Postoperative complications were registered in a 3 months follow-up (early observation) and after 6 months (long-term observation). Patients with tongue-type fractures had significantly better surgical outcomes than patients with depression-type fractures. Displacements of bone fragments in articular calcaneal fractures visualized radiographically by the changes of Harnroongroj et al. angle do not constitute a serious surgical problem and are easily repositioned and stabilized, as opposed to displacements resulting in changes in the value of the Böhler angle. The most common postoperative complications were local inflammatory reactions at the point of entry of fixation material and thromboembolic complications. Results of surgical treatment of articular fractures of the calcaneus using a minimally invasive percutaneous fixation are good and satisfactory in majority of patients suggesting that this method constitutes proper choice of treatment.


Assuntos
Calcâneo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Fraturas Intra-Articulares/cirurgia , Adulto , Calcâneo/diagnóstico por imagem , Calcâneo/lesões , Feminino , Fraturas Ósseas/diagnóstico por imagem , Humanos , Fraturas Intra-Articulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Radiografia , Recuperação de Função Fisiológica , Resultado do Tratamento , Adulto Jovem
18.
Genome Announc ; 5(45)2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29122855

RESUMO

Four lytic phages, vB_KpnP_BIS33, vB_KpnP_IL33, and vB_KpnP_PRA33 of the Podoviridae family and vB_KpnM_BIS47 of the Myoviridae family, which act against animal-pathogenic Klebsiella pneumoniae strains, were isolated from sewage plants in Poland. They possess double-stranded DNA genomes of 41,697 bp, 41,335 bp, 40,605 bp, and 147,443 bp, respectively.

19.
Bioconjug Chem ; 28(7): 1834-1841, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28482148

RESUMO

The use of phage display to identify peptides with an ability to bind and synthesize Eu2O3 nanoparticles is demonstrated in this report. This is the first report of modified phages specifically binding a lanthanide. The peptides exposed on virions revealed very strong binding to Eu2O3 nanoparticles and the ability to catalyze Eu2O3 nanoparticles' formation from Eu(OH)3 and Eu(NO3)3 solutions. The luminescence emission spectrum of Eu3+ ions indicated that these ions existed mostly in sites deviated from the inversion symmetry in crystalline Eu2O3 aggregates and gelatinous Eu(OH)3 precipitate. The ability of phage-displayed peptides to catalyze formation of Eu2O3 nanoparticles provides a useful tool for a low-cost and effective synthesis of lanthanide nanoparticles, which serve as attractive biomedical sensors or fluorescent labels, among their other applications.


Assuntos
Bacteriófagos/metabolismo , Európio/química , Nanopartículas/química , Biblioteca de Peptídeos , Catálise , Európio/metabolismo , Hidróxidos , Nanopartículas/metabolismo , Nitratos , Peptídeos , Vírion/química
20.
Bioconjug Chem ; 27(12): 2900-2910, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-27748604

RESUMO

With the advent of nanotechnology, carbon nanomaterials such as carbon nanofibers (CNF) have aroused substantial interest in various research fields, including energy storage and sensing. Further improvement of their properties might be achieved via the application of viral particles such as bacteriophages. In this report, we present a filamentous M13 bacteriophage with a point mutation in gene VII (pVII-mutant-M13) that selectively binds to the carbon nanofibers to form 3D structures. The phage-display technique was utilized for the selection of the pVII-mutant-M13 phage from the phage display peptide library. The properties of this phage make it a prospective candidate for a scaffold material for CNFs. The results for binding of CNF by mutant phage were compared with those for maternal bacteriophage (pVII-M13). The efficiency of binding between pVII-mutant-M13 and CNF is about 2 orders of magnitude higher compared to that of the pVII-M13. Binding affinity between pVII-mutant-M13 and CNF was also characterized using atomic force microscopy, scanning electron microscopy, and transmission electron microscopy, which confirmed the specificity of the interaction of the phage pVII-mutant-M13 and the CNF; the binding occurs via the phage's ending, where the mutated pVII protein is located. No similar behavior has been observed for other carbon nanomaterials such as graphite, reduced graphene oxide, single-walled carbon nanotubes, and multiwalled carbon nanotubes. Infrared spectra confirmed differences in the interaction with CNF between the pVII-mutant-M13 and the pVII-M13. Basing on conducted research, we hypothesize that the interactions are noncovalent in nature, with π-π interactions playing the dominant role. Herein, the new bioconjugate material is introduced.


Assuntos
Bacteriófago M13/química , Bacteriófago M13/metabolismo , Nanofibras/química , Bacteriófago M13/genética , Grafite/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Mutação Puntual , Espectrofotometria Infravermelho
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