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1.
Biomedicines ; 12(4)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38672283

RESUMO

The authors would like to add the following clarification regarding the clinical trials evaluating the probiotic product VSL#3 cited in the published paper [...].

2.
Pathogens ; 12(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36986352

RESUMO

Dysbiosis of the gut microbiota, caused by antibiotics, plays a key role in the establishment of Clostridioides difficile CD). Toxin-producing strains are involved in the pathogenesis of Clostridioides difficile infection (CDI), one of the most common hospital-acquired infections. We cultured a total of 84 C. difficile isolates from stool samples of patients hospitalized at Louis Pasteur University Hospital in Kosice, Slovakia, that were suspected of CDI and further characterized by molecular methods. The presence of genes encoding toxin A, toxin B, and binary toxin was assessed by toxin-specific PCR. CD ribotypes were detected using capillary-based electrophoresis ribotyping. A total of 96.4% of CD isolates carried genes encoding toxins A and B, and 54.8% of them were positive for the binary toxin. PCR ribotyping showed the presence of three major ribotypes: RT 176 (n = 40, 47.6%); RT 001 (n = 23, 27.4%); and RT 014 (n = 7, 8.3%). Ribotype 176 predominated among clinical CD isolates in our hospital. The proportion of RT 176 and RT 001 in four hospital departments with the highest incidence of CDI cases was very specific, pointing to local CDI outbreaks. Based on our data, previous use of antibiotics represents a significant risk factor for the development of CDI in patients over 65 years of age.

3.
Biomedicines ; 12(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38255150

RESUMO

Transplantation of faecal microbiota (FMT) is generally considered a safe therapeutic procedure with few adverse effects. The main factors that limit the spread of the use of FMT therapy for idiopathic inflammatory bowel disease (IBD) are the necessity of minimising the risk of infection and transfer of another disease. Obtaining the animal model of UC (ulcerative colitis) by exposure to DSS (dextran sodium sulphate) depends on many factors that significantly affect the result. Per os intake of DSS with water is individual for each animal and results in the development of a range of various forms of induced UC. For this reason, the aim of our study was to evaluate the modulation and regenerative effects of FMT on the clinical and histopathological responses and the changes in the bowel microenvironment in pseudo germ-free (PGF) mice of the BALB/c line subjected to chemical induction of mild, moderate and serious forms of UC. The goal was to obtain new data related to the safety and effectiveness of FMT that can contribute to its improved and optimised use. The animals with mild and moderate forms of UC subjected to FMT treatment exhibited lower severity of the disease and markedly lower damage to the colon, including reduced clinical and histological disease index and decreased inflammatory response of colon mucosa. However, FMT treatment failed to achieve the expected therapeutic effect in animals with the serious form of UC activity. The results of our study indicated a potential safety risk involving development of bacteraemia and also translocation of non-pathogenic representatives of bowel microbiota associated with FMT treatment of animals with a diagnosed serious form of UC.

4.
World J Gastroenterol ; 28(27): 3370-3382, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-36158273

RESUMO

Colorectal cancer (CRC) is a leading cause of human mortality worldwide. As conventional anticancer therapy not always being effective, there is growing interest in innovative "drug-free" cancer treatments or interventions that improve the efficacy of established therapy. CRC is associated with microbiome alterations, a process known as dysbiosis that involves depletion and/or enrichment of particular gut bacterial species and their metabolic functions. Supplementing patient treatment with traditional probiotics (with or without prebiotics), next-generation probiotics (NGP), or postbiotics represents a potentially effective and accessible complementary anticancer strategy by restoring gut microbiota composition and/or by signaling to the host. In this capacity, restoration of the gut microbiota in cancer patients can stabilize and enhance intestinal barrier function, as well as promote anticarcinogenic, anti-inflammatory, antimutagenic or other biologically important biochemical pathways that show high specificity towards tumor cells. Potential benefits of traditional probiotics, NGP, and postbiotics include modulating gut microbiota composition and function, as well as the host inflammatory response. Their application in CRC prevention is highlighted in this review, where we consider supportive in vitro, animal, and clinical studies. Based on emerging research, NGP and postbiotics hold promise in establishing innovative treatments for CRC by conferring physiological functions via the production of dominant natural products and metabolites that provide new host-microbiota signals to combat CRC. Although favorable results have been reported, further investigations focusing on strain and dose specificity are required to ensure the efficacy and safety of traditional probiotics, NGP, and postbiotics in CRC prevention and treatment.


Assuntos
Produtos Biológicos , Neoplasias Colorretais , Terapias Complementares , Probióticos , Animais , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/prevenção & controle , Disbiose/microbiologia , Humanos , Prebióticos , Probióticos/uso terapêutico
5.
Biomedicines ; 10(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36140337

RESUMO

Although there are number of available therapies for ulcerative colitis (UC), many patients are unresponsive to these treatments or experience secondary failure during treatment. Thus, the development of new therapies or alternative strategies with minimal side effects is inevitable. Strategies targeting dysbiosis of gut microbiota have been tested in the management of UC due to the unquestionable role of gut microbiota in the etiology of UC. Advanced molecular analyses of gut microbiomes revealed evident dysbiosis in UC patients, characterized by a reduced biodiversity of commensal microbiota. Administration of conventional probiotic strains is a commonly applied approach in the management of the disease to modify the gut microbiome, improve intestinal barrier integrity and function, and maintain a balanced immune response. However, conventional probiotics do not always provide the expected health benefits to a patient. Their benefits vary significantly, depending on the type and stage of the disease and the strain and dose of the probiotics administered. Their mechanism of action is also strain-dependent. Recently, new candidates for potential next-generation probiotics have been discovered. This could bring to light new approaches in the restoration of microbiome homeostasis and in UC treatment in a targeted manner. The aim of this paper is to provide an updated review on the current options of probiotic-based therapies, highlight the effective conventional probiotic strains, and outline the future possibilities of next-generation probiotic and postbiotic supplementation and fecal microbiota transplantation in the management of UC.

6.
Gen Physiol Biophys ; 39(4): 301-318, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32902401

RESUMO

A soil bacterium MR-CH-I15-I was on the base of phylogenetic analysis of almost the whole (1,492 bp) 16S rRNA sequence and sequences of selected 9 marker genes identified as Pseudomonas putida strain NM-CH-I15-I. The bacterium exhibited typical morphological features and biochemical properties for this species, the highest resistance to nickel and copper and multidrug resistance to different antibiotic groups. In addition, the whole czcA-NM15I heavy-metal resistance gene sequence (3,126 bp, 1,042 amino acids, MW 112, 138 Da) was obtained and on the base of phylogenetic analysis was assigned to CzcA protein from Pseudomonas reidholzensis with 93% similarity. This gene was significantly induced mainly by the addition of zinc, cadmium and cobalt and in a lesser extent of nickel. Furthermore, an increased expression of the CzcA-NM15I protein was confirmed by immunoblot analysis after heterologous expression of the czcA-NM15I synthetic variant gene in E. coli BL21 (DE3). Finally, the location of amino acids (R83, R673, D402, D408, D619, E415, E568) in the homology model of the CzcA-NM15I protein suggested that these amino acids may play an important role in the transport of cations such as cobalt, zinc or cadmium. This soil bacterium can represent a new type strain of P. putida NM-CH-I15-I.


Assuntos
Níquel , Filogenia , Pseudomonas putida/classificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Pseudomonas putida/isolamento & purificação , RNA Ribossômico 16S , Análise de Sequência de DNA , Eslováquia , Poluentes do Solo
7.
Antioxidants (Basel) ; 9(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32718101

RESUMO

Hybrid B heme peroxidases are recently discovered unique oxidoreductases present solely in the fungal kingdom. We have investigated two typical representatives from Magnaporthe oryzae-one of the most dangerous phytopathogens known as a causal agent of the rice blast disease. First, we focused on native expression of two detected hyBpox paralogs by the means of reverse-transcription quantitative real-time PCR. Our results indicate a 7-fold induction of the MohyBpox1 transcript in a medium with H2O2 and a 3-fold induction in a medium with peroxyacetic acid. For the MohyBpox2 paralog the induction patterns were up to 12-fold and 6.7-fold, respectively. We have successfully expressed the shorter gene, MohyBpox1, heterologously in Pichia pastoris for detailed characterization. Observed biochemical and biophysical properties of the highly purified protein reveal that a typical HyBPOX is significantly different from previously investigated APx-CcP hybrids. This newly discovered secretory peroxidase reveals a Soret maximum at 407 nm, Q bands at 532 and 568 nm, CT band at 625 nm and a purity number of 1.48. Electron paramagnetic resonance (EPR) analysis suggests a mixture of high and low spin species in the ferric state dependent on calcium contents. Steady-state kinetic data reveal the highest peroxidase activity with ABTS, 5-aminosalycilate and efficient oxidation of tyrosine. MoHyBPOX1 as a fusion protein consists of two domains. The longer conserved N-terminal peroxidase domain is connected with a shorter C-terminal domain containing a carbohydrate binding motif of type CBM21. We demonstrate the capacity of MoHyBPOX1 to bind soluble starch efficiently. Potential involvement of hybrid peroxidases in the pathogenicity of M. oryzae is discussed.

8.
Ecotoxicol Environ Saf ; 181: 481-490, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228824

RESUMO

Peroxidases and catalases are well-known antioxidant enzymes produced in almost all living organisms for the elimination of reactive oxygen species (ROS) and thus they prevent the occurrence of oxidative stress. In our study we focused on two soil fungi of the family Chaetomiaceae (mesophilic Chaetomium cochliodes and its thermophilic counterpart C. thermophilum var. dissitum) in order to explore the presence of peroxidase and catalase genes, formation of their native transcripts and protective effect of corresponding translation products in a case study. Predicted genes of our interest were confirmed by genomic PCR and their inducible transcripts by RT-PCR. We were able to quantify the expression levels of newly discovered fungal heme peroxidases and catalases with the reverse-transcription quantitative real-time PCR method. We compared obtained quantitative levels of mRNA production with the level of corresponding extracellular protein occurrence as detected with monitoring their specific peroxidase and catalase activities directly in the cultivation media at optimal growth temperatures. The presence of secretory Catalase 2 from C. thermophilum var. dissitum was detected and identified with mass spectrometry approach directly in the growth medium. This unique catalase is phylogenetically closely related with a previously described catalase-phenol oxidase thus representing an effective and versatile antioxidant in the environment of the fungal mycelia also involved in the catabolism of recalcitrant phenolic substances.


Assuntos
Ascomicetos/metabolismo , Catalase/metabolismo , Espaço Extracelular/enzimologia , Estresse Oxidativo , Peroxidases/metabolismo , Antioxidantes/metabolismo , Ascomicetos/classificação , Ascomicetos/enzimologia , Ascomicetos/genética , Catalase/genética , Meios de Cultura/metabolismo , Espaço Extracelular/metabolismo , Oxirredução , Peroxidases/genética , Filogenia , Temperatura
9.
Pol J Microbiol ; 67(2): 191-201, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30015457

RESUMO

A bacterial isolate MR-CH-I2 [KC809939] isolated from soil contaminated mainly by high nickel concentrations in southwest Slovakia was previously found carrying nccA-like heavy-metal resistance determinant, marked as MR-CH-I2-HMR [KF218096]. According to phylogenetic analysis of short (696 bp) 16S rDNA (16S rRNA) sequences this bacterium was tentatively assigned to Uncultured beta proteobacterium clone GC0AA7ZA05PP1 [JQ913301]. nccA-like gene product was on the same base of its partial (581 bp) sequences tentatively assigned to CzcA family heavy metal efflux pump [YP_001899332] from Ralstonia picketii 12J with 99% similarity. In this study the bacterium MR-CH-I2 and its heavy-metal resistance determinant were more precisely identified. This bacterial isolate was on the base of phylogenetic analysis of almost the whole (1,500 bp) 16S rDNA (16S rRNA) sequence, MR-CH-I2 [MF102046], and sequence for gyrB gene and its product respectively, MR-CH-I2-gyrB [MF134666], assigned to R. picketii 12J [CP001068] with 99 and 100% similarities, respectively. In addition, the whole nccA-like heavy-metal resistance gene sequence (3,192 bp), marked as MR-CH-I2-nccA [KR476581], was obtained and on the base of phylogenetic analysis its assignment was confirmed to MULTISPECIES: cation efflux system protein CzcA [WP_004635342] from Burkholderiaceae with 98% similarity. Furthermore, although the bacterium carried one high molecular plasmid of about 50 kb in size, nccA-like gene was not located on this plasmid. Finally, the results from RT-PCR analysis showed that MR-CH-I2-nccA gene was significantly induced only by the addition of nickel.


Assuntos
Bactérias/classificação , Níquel/metabolismo , Filogenia , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/efeitos dos fármacos , DNA Bacteriano/genética , Metais Pesados , Plasmídeos/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Eslováquia
10.
Gene ; 666: 83-91, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-29738837

RESUMO

Catalase-peroxidases represent one important subfamily of ancestral antioxidant enzymes originally evolved in bacteria for the protection against various forms of oxidative stress. KatG genes coding for these bifunctional catalase-peroxidases were during their peculiar evolution transferred from Bacteroidetes to the fungal phylum Ascomycota via a horizontal gene transfer event. Here we analyse a newly discovered fungal katG gene without introns coding for a thermostable catalase-peroxidase from Chaetomium thermophilum var. dissitum and compare it with closely related thermophilic and mesophilic katGs and their translation products. We show that CthediskatG gene resembling its bacterial counterparts has a typical eukaryotic transcription start site and also contains a conserved eukaryotic polyadenylation signal behind its 3' terminus. Moreover, we have detected polyA tails in corresponding transcripts of katG from two different mRNA libraries of C. thermophilum var. disstum. Although otherwise highly conserved, only in katG genes of two C. thermophilum variants a unique 60 bp long deletion leading in the translated product with high probability to a modified loop and thus access to the prosthetic heme group was observed. We also present an updated molecular phylogeny revealing the evolutionary position of fungal thermostable catalase-peroxidases within a robust phylogenetic tree of the whole KatG subfamily.


Assuntos
Catalase/genética , Chaetomium/genética , Proteínas Fúngicas/genética , Peroxidase/genética , Sequência de Aminoácidos , Catalase/química , Catalase/metabolismo , Domínio Catalítico , Chaetomium/enzimologia , Chaetomium/crescimento & desenvolvimento , Sequência Conservada , Estabilidade Enzimática , Evolução Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Expressão Gênica , Temperatura Alta , Modelos Moleculares , Peroxidase/química , Peroxidase/metabolismo , Filogenia , Conformação Proteica em alfa-Hélice
11.
BMC Genomics ; 17(1): 763, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27681232

RESUMO

BACKGROUND: The ascomycetous family Chaetomiaceae (class Sordariomycetes) includes numerous soilborn, saprophytic, endophytic and pathogenic fungi which can adapt to various growth conditions and living niches by providing a broad armory of oxidative and antioxidant enzymes. RESULTS: We release the 34.7 Mbp draft genome of Chaetomium cochliodes CCM F-232 consisting of 6036 contigs with an average size of 5756 bp and reconstructed its phylogeny. We show that this filamentous fungus is closely related but not identical to Chaetomium globosum and Chaetomium elatum. We screened and critically analysed this genome for open reading frames coding for essential antioxidant enzymes. It is demonstrated that the genome of C. cochliodes contains genes encoding putative enzymes from all four known heme peroxidase superfamilies including bifunctional catalase-peroxidase (KatG), cytochrome c peroxidase (CcP), manganese peroxidase, two paralogs of hybrid B peroxidases (HyBpox), cyclooxygenase, linoleate diol synthase, dye-decolorizing peroxidase (DyP) of type B and three paralogs of heme thiolate peroxidases. Both KatG and DyP-type B are shown to be introduced into ascomycetes genomes by horizontal gene transfer from various bacteria. In addition, two putative large subunit secretory and two small-subunit typical catalases are found in C. cochliodes. We support our genomic findings with quantitative transcription analysis of nine peroxidase & catalase genes. CONCLUSIONS: We delineate molecular phylogeny of five distinct gene superfamilies coding for essential heme oxidoreductases in Chaetomia and from the transcription analysis the role of this antioxidant enzymatic armory for the survival of a peculiar soil ascomycete in various harsh environments.

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