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1.
Microbiol Resour Announc ; 13(4): e0001924, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38501776

ABSTRACT

In this study, we present the genome sequence of Umezawaea sp. strain Da 62-37, which was isolated from the rhizosphere of Deschampsia antarctica E.Desv. (Galindez Island, maritime Antarctic). The de novo assembly produced one contig, with a length of 11,793,683 bp. AntiSMASH analysis indicated 49 biosynthetic gene clusters.

2.
Microbiol Resour Announc ; 13(1): e0086523, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38014936

ABSTRACT

In this study, we present the draft genome sequence of the Enterococcus sp. strain SB12, which was isolated from artisanal cheese of the Carpathian region (Ukraine). The de novo assembly produced 64 contigs, with a total length of 2,514,601 bp. Phylogenetic analysis revealed its proximity to the Enterococcus faecium strains.

3.
Folia Microbiol (Praha) ; 68(4): 645-653, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36947395

ABSTRACT

Microbial natural products are among the main sources of compounds used in the medical biotechnology field for the purpose of drug development. However, as antibiotic resistance in pathogenic microorganisms is known to be increasing dramatically, there exists a need to develop new antibiotics. Actinomycetia have proven to be a good source of biologically active compounds, although the rediscovery of previously known compounds significantly slows down the introduction of new antibiotics. As a consequence, increasing attention is being paid to the isolation of actinomycete strains from previously unexplored sources, which can significantly increase the likelihood of discovering new biologically active compounds. This study investigated the diversity and bioactive potential of 372 actinomycete strains isolated from the rhizosphere soil of Juniperus excelsa M. Bieb. The examined actinomycete strains belonged to 11 genera, namely, Actinoplanes, Actinorectispora, Amycolatopsis, Kribbella, Micrococcus, Micromonospora, Nocardia, Promicromonospora, Rhodococcus, Saccharopolyspora and Streptomyces. The bioactive potential of each isolated actinomycete strain was determined on the basis of its ability to produce antimicrobial metabolites against Gram-positive and Gram-negative bacteria and yeast. Some 159 strains (42.74%) exhibited antimicrobial activity against at least one of the tested microbial strains. The dereplication analysis of the extract of the Streptomyces sp. Je 1-651 strain, which exhibited strong antimicrobial activity, led to the annotation of spiramycins and stambomycins. Moreover, the phylogenetic analysis based on the 16S rRNA gene sequence of the Je 1-651 strain revealed it to be close to the S. ambofaciens.


Subject(s)
Actinobacteria , Actinomycetales , Anti-Infective Agents , Juniperus , Streptomyces , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Juniperus/genetics , Rhizosphere , Phylogeny , RNA, Ribosomal, 16S/genetics , Soil , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria , Actinomycetales/genetics , Streptomyces/genetics , Soil Microbiology
4.
Planta ; 254(6): 129, 2021 Nov 24.
Article in English | MEDLINE | ID: mdl-34817648

ABSTRACT

MAIN CONCLUSION: The recombinant PsDef5.1 defensin inhibits the growth of phytopathogenic fungi, Gram-positive and Gram-negative bacteria, and human pathogen Candida albicans. Expression of seed-derived Scots pine defensins is tissue-specific and developmentally regulated. Plant defensins are ubiquitous antimicrobial peptides that possess a broad spectrum of activities and multi-functionality. The genes for these antimicrobial proteins form a multigenic family in the plant genome and are expressed in every organ. Most of the known defensins have been isolated from seeds of various monocot and dicot species, but seed-derived defensins have not yet been characterized in gymnosperms. This study presents the isolation of two new 249 bp cDNA sequences from Scots pine seeds with 97.9% nucleotide homology named PsDef5.1 and PsDef5.2. Their deduced amino acid sequences have typical plant defensin features, including an endoplasmic reticulum signal sequence of 31 amino acids (aa), followed by a characteristic defensin domain of 51 aa. To elucidate the functional activity of new defensins, we expressed the mature form of PsDef5.1 in a prokaryotic system. The purified recombinant peptide exhibited activity against the phytopathogenic fungi and Gram-negative and Gram-positive bacteria with the IC50 of 5-18 µM. Moreover, it inhibited the growth of the human pathogen Candida albicans with the IC50 of 6.0 µM. Expression analysis showed that transcripts of PsDef5.1-2 genes were present in immature and mature pine seeds and different parts of seedlings at the early stage of germination. In addition, unlike the PsDef5.2, the PsDef5.1 gene was expressed in the reproductive organs. Our findings indicate that novel defensins are promising candidates for transgenic application and the development of new antimicrobial drugs.


Subject(s)
Anti-Bacterial Agents , Defensins , Candida albicans , Defensins/genetics , Gram-Negative Bacteria , Gram-Positive Bacteria , Seeds
5.
J Chromatogr A ; 1330: 1-5, 2014 Feb 21.
Article in English | MEDLINE | ID: mdl-24468238

ABSTRACT

Vortex-assisted liquid-liquid microextraction (VALLME) coupled with high-performance liquid chromatography (HPLC) is proposed here for the rapid determination of octanol-water partitioning coefficients (Kow). VALLME uses vortex agitation, a mild emulsification procedure, to disperse microvolumes of octanol in the aqueous phase thus increasing the interfacial contact area and ensuring faster partitioning rates. With VALLME, 2min were enough to achieve equilibrium conditions between the octanolic and aqueous phases. Upon equilibration, separation was achieved using centrifugation and the octanolic microdrop was collected and analyzed in a HPLC system. Six model compounds with logKow values ranging between ∼0.5 and 3.5 were used during the present investigations. The proposed method produced logKow values that were consistent with previously published values and the recorded uncertainty was well within the acceptable log unit range. Overall, the key features of the proposed Kow determination procedure comprised speed, reliability, simplicity, low cost and minimal solvent consumption.


Subject(s)
Liquid Phase Microextraction/methods , Octanols/chemistry , Water/chemistry , Chlorophenols/analysis , Chromatography, High Pressure Liquid/methods , Dichlorvos/analysis , Emulsions , Hydroquinones/analysis , Naphthalenes/analysis , Reproducibility of Results , Simazine/analysis , Solvents
6.
Anal Chim Acta ; 691(1-2): 56-61, 2011 Apr 08.
Article in English | MEDLINE | ID: mdl-21458631

ABSTRACT

Fast screening of trace amounts of the perfluorooctane sulfonate anion (PFOS) in water samples was performed following a simple, fast and efficient sample preparation procedure based on vortex-assisted liquid-liquid microextraction (VALLME) prior to liquid chromatography-mass spectrometry. VALLME initially uses vortex agitation, a mild emulsification procedure to disperse microvolumes of octanol, a low density extractant solvent, in the aqueous sample. Microextraction under equilibrium conditions is thus achieved within few minutes. Subsequently, centrifugation separates the two phases and restores the initial microdrop shape of the octanol acceptor phase, which can be collected and used for liquid chromatography-single quadrupole mass spectrometry analysis. Several experimental parameters were controlled and the optimum conditions found were: 50 µL of octanol as the extractant phase; 20 mL aqueous donor samples (pH=2); a 2 min vortex extraction time with the vortex agitator set at a 2500 rpm rotational speed; no ionic strength adjustment. Centrifugation for 2 min at 3500 rpm yielded separation of the two phases throughout this study. Enhanced extraction efficiencies were observed at low pH which was likely due to enhanced electrostatic interaction between the negatively PFOS molecules and the positively charged octanol/water interface. The effect of pH was reduced in the presence of sodium chloride, likely due to electrical double layer compression. The linear response range for PFOS was from 5 to 500 ng L(-1) (coefficient of determination, r(2), 0.997) and the relative standard deviation for aqueous solutions containing 10 and 500 ng L(-1) PFOS were 7.4% and 6.5%, respectively. The limit of detection was 1.6 ng L(-1) with an enrichment factor of approximately 250. Analysis of spiked tap, river and well water samples revealed that matrix did not affect extraction.

7.
J Chromatogr A ; 1218(18): 2467-75, 2011 May 06.
Article in English | MEDLINE | ID: mdl-21411104

ABSTRACT

A sensitive analytical method to concentrate and determine extensively used UV filters in cosmetic products at (ultra)trace levels in water samples is presented. The method is based on a sample treatment using dispersive solid-phase extraction (dSPE) with laboratory-made chemisorbed oleic acid-coated cobalt ferrite (CoFe(2)O(4)@oleic acid) magnetic nanoparticles (MNPs) as optimized sorbent for the target analytes. The variables involved in dSPE were studied and optimized in terms of sensitivity, and the optimum conditions were: mass of sorbent, 100mg; donor phase volume, 75 mL; pH, 3; and sodium chloride concentration, 30% (w/v). After dSPE, the MNPs were eluted twice with 1.5 mL of hexane, and then the eluates were evaporated to dryness and reconstituted with 50 µL of N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) for the injection into the gas chromatography-mass spectrometry (GC-MS). Under the optimized experimental conditions the method provided good levels of repeatability with relative standard deviations below 16% (n=5, at 100 ng L(-1) level). Limit of detection values ranged between 0.2 and 6.0 ng L(-1), due to the high enrichment factors achieved (i.e., 453-748). Finally, the proposed method was applied to the analysis of water samples of different origin (tap, river and sea). Recovery values showed that the matrices under consideration do not significantly affect the extraction process.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Magnetite Nanoparticles/chemistry , Oleic Acid/chemistry , Solid Phase Extraction/methods , Sunscreening Agents/analysis , Water Pollutants, Chemical/analysis , Hydrogen-Ion Concentration , Osmolar Concentration , Reproducibility of Results , Rivers , Sensitivity and Specificity , Water
8.
J Chromatogr A ; 1216(9): 1290-5, 2009 Feb 27.
Article in English | MEDLINE | ID: mdl-19144344

ABSTRACT

A simple and commercial readily-available approach that enables the direct use of ionic liquid (IL)-based single-drop microextraction (SDME) prior to gas chromatography (GC) is presented. The approach is based on thermal desorption (TD) of the analytes from the IL droplet to the GC system, by using a robust and commercially-available thermodesorption system. For this purpose, a two-glass-tube concentrically disposed system was designed. The inner tube is a laboratory-cut Pyrex tube (20mm length) that houses the ionic liquid droplet from the SDME process, and the outer tube is a commercially-available TD glass tube (187 mm length) commonly employed for stir-bar sorptive extractions (SBSE). In this way, the proposed device prevents IL from entering the GC system, as this could dirty the inlet or even block the column. The determination of 10 chlorobenzenes in water samples by GC coupled with mass spectrometric (MS) detection has been chosen as model analytical application, showing the feasibility of the proposed approach. The SDME process consists of a 5 microL droplet of 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]) suspended in the headspace (HS) of a 10 mL stirred sample. After extracting for 37 min at room temperature, the IL droplet is directly placed into the small inner tube, which is placed into the TD tube. The whole device is placed inside the TD unit, where desorption of the analytes is performed at 240 degrees C for 5 min with a helium flow rate of 100 mL min(-1). The analytical figures of merit of the proposed IL-(HS)-SDME-TD-GC-MS approach are very suitable for the determination of chlorobenzenes at ultratrace levels, with relative standard deviation values ranging between 2% and 17%, and limits of detection ranging between 1 and 4 ng L(-1), showing the potential offered by the IL-based SDME process with GC.


Subject(s)
Chemical Fractionation , Chlorobenzenes/analysis , Gas Chromatography-Mass Spectrometry/methods , Water/chemistry , Chemical Fractionation/instrumentation , Chemical Fractionation/methods , Ionic Liquids/chemistry , Models, Chemical , Rivers/chemistry , Sensitivity and Specificity , Temperature
9.
Am Surg ; 74(10): 967-72, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18942624

ABSTRACT

The purpose of this study was to assess the impact of new technology on both the understanding of the underlying pathophysiology and treatment of solitary rectal ulcer syndrome (SRUS). This study is a retrospective review of patients with a histologic diagnosis of SRUS (1993 to 2007) complimented with a prospective database of those patients studied with defecography and dynamic pelvic MRI. Thirty patients were available for evaluation. A polyp or mass was present in 74 per cent. Ulcers were found in only 23 per cent. All 12 patients undergoing defecography demonstrated rectorectal intussusception. Dynamic MRI of the pelvis revealed pronounced anorectal redundancy and lack of mesorectosacral fixation with mild to severe pelvic floor descent in all four patients studied. Fiber with or without stool softeners was the initial treatment in all patients with resolution of symptoms in 65 per cent. One patient with refractory symptoms underwent a stapled transanal rectal resection with complete resolution of symptoms. Occult rectorectal intussusception appears to be the operant anatomic pathology in SRUS. Anorectal redundancy with lack of mesorectosacral fixation may contribute to the process. All patients should be studied with defecography and dynamic MRI. Stapled transanal rectal resection may offer a promising surgical option.


Subject(s)
Colectomy/methods , Dietary Fiber/therapeutic use , Rectal Diseases/diagnosis , Ulcer/diagnosis , Adolescent , Adult , Aged , Colonoscopy , Defecography , Diagnosis, Differential , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prognosis , Rectal Diseases/therapy , Retrospective Studies , Syndrome , Ulcer/therapy
10.
Rev. Fac. Odontol. Univ. Antioq ; 7(1): 41-7, oct. 1995. ilus
Article in Spanish | LILACS | ID: lil-166229

ABSTRACT

Las placas oclusales constituyen alternativas de manejo de los problemas musculares y articulares. Cuando existen factores etiológicos de los desórdenes musculares y articulares es aconsejable que la terapia inicial sea reversible y no invasiva. Luego, es extremadamente importante identificar la relación causa-efecto antes de que se inicie la terapia irreversible


Subject(s)
Bruxism/physiopathology , Bruxism/therapy , Occlusal Splints , Temporomandibular Joint Dysfunction Syndrome/therapy , Dental Occlusion, Centric/standards
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