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1.
BMJ Case Rep ; 17(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373813

RESUMO

In up to 2% of the population, benign tumours called lipomas can develop. When they are more than 5 cm, they are considered giant lipomas. Giant lipomas of the distal forearm and hand may cause compression to the underlying tissues, nerves and muscles, even though they are typically asymptomatic. An older woman with soft tissue swelling in her right wrist and forearm, and numbness and pain in her right hand presented to the general surgery outpatient clinic. Her numb fingers indicated that the median nerve was compressed, and an MRI scan of her wrist and forearm revealed median nerve compression due to a giant lipoma with a dimension of about 9.2×3.4×4 cm. A surgical excision was done with an intraoperative nerve stimulator, and the specimen sent for histopathology confirmed the diagnosis of lipoma. Pain, numbness and motor power improved within 1 week postoperatively, and the patient was discharged.


Assuntos
Síndrome do Túnel Carpal , Lipoma , Feminino , Humanos , Idoso , Punho/diagnóstico por imagem , Punho/patologia , Síndrome do Túnel Carpal/diagnóstico por imagem , Síndrome do Túnel Carpal/etiologia , Síndrome do Túnel Carpal/cirurgia , Antebraço/patologia , Hipestesia/etiologia , Lipoma/complicações , Lipoma/diagnóstico por imagem , Lipoma/cirurgia , Dor/complicações
2.
Plants (Basel) ; 13(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38337962

RESUMO

Chickpea (Cicer arietinum L.), encompassing the desi and kabuli varieties, is a beloved pulse crop globally. Its cultivation spans over fifty countries, from the Indian subcontinent and southern Europe to the Middle East, North Africa, the Americas, Australia, and China. With a rich composition of carbohydrates and protein, constituting 80% of its dry seed mass, chickpea is also touted for its numerous health benefits, earning it the title of a 'functional food'. In the past two decades, research has extensively explored the rhizobial diversity associated with chickpea and its breeding in various countries across Europe, Asia, and Oceania, aiming to understand its impact on the sustainable yield and quality of chickpea crops. To date, four notable species of Mesorhizobium-M. ciceri, M. mediterraneum, M. muleiense, and M. wenxiniae-have been reported, originally isolated from chickpea root nodules. Other species, such as M. amorphae, M. loti, M. tianshanense, M. oportunistum, M. abyssinicae, and M. shonense, have been identified as potential symbionts of chickpea, possibly acquiring symbiotic genes through lateral gene transfer. While M. ciceri and M. mediterraneum are widely distributed and studied across chickpea-growing regions, they remain absent in China, where M. muleiense and M. wenxiniae are the sole rhizobial species associated with chickpea. The geographic distribution of chickpea rhizobia is believed to be influenced by factors such as genetic characteristics, competitiveness, evolutionary adaptation to local soil conditions, and compatibility with native soil microbes. Inoculating chickpea with suitable rhizobial strains is crucial when introducing the crop to new regions lacking indigenous chickpea rhizobia. The introduction of a novel chickpea variety, coupled with the effective use of rhizobia for inoculation, offers the potential not only to boost the yield and seed quality of chickpeas, but also to enhance crop productivity within rotation and intercropped systems involving chickpea and other crops. Consequently, this advancement holds the promise to drive forward the cause of sustainable agriculture on a global scale.

3.
BMJ Case Rep ; 16(12)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123322

RESUMO

Adult ileocecal intussusception due to non-specific inflammation is a rare condition. Intussusception is the intestinal segment telescoping into the adjacent intestinal lumen. Typically, a pathological lesion is discovered with a high percentage of malignancy. Intussusception of the most common ileocolic kind includes the appendix, but it is uncommon for an appendix to serve as the lead point. The patient was admitted to the emergency department with a complaint of acute intestinal obstruction. After getting a diagnostic workup, an exploratory laparotomy was done, and the ileocecal and ascending colon segment was intussuscepted directly into the sigmoid colon. Transverse and descending colon were normal, and resection of necrosed intussuscepted bowel, primary repair of sigmoid colon with ileostomy with transverse colon as distal mucus fistula done, after the 3-month restoration of bowel continuity done, patient discharged and doing well. After the diagnosis of intussusception, the best surgical choice is in the hands of an experienced surgeon.


Assuntos
Obstrução Intestinal , Intussuscepção , Adulto , Humanos , Intussuscepção/diagnóstico por imagem , Intussuscepção/etiologia , Colo Sigmoide/diagnóstico por imagem , Colo Sigmoide/cirurgia , Obstrução Intestinal/cirurgia , Inflamação
4.
Curr Pharm Biotechnol ; 24(1): 50-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35619298

RESUMO

Nucleic acids (DNA and RNA) hold great potential for the advancement of future medicine but suffer from unsatisfactory clinical success due to the challenges accompanied with their delivery. Nucleic acid-mediated nanomaterials have riveted the researchers from the past two decades and exhilarating tasks have prevailed. Nucleic acid nanotechnology offers unique control over the shape, size, time, mechanics and anisotropy. It can transfect numerous types of tissues and cells without any toxic effect, minimize the induced immune response, and penetrate most of the biological barriers and hence it reveals itself as a versatile tool for multidisciplinary research field and for various therapeutic purposes. Nucleic acid combines with other nanoscale objects also by altering the chemical functional groups and reproducing the varied array of nanomaterials. Interestingly, nucleic acidderived nanomaterials are characterized easily at atomic level accuracy. However, this advent of nanoscience has vital issues which must be addressed, such as the high cost of nucleic acids, their self-assembly nature, etc. Hence, the aim of this review is to highlight the systematic advances and methodology of nucleic acid-mediated synthesis of nanomaterials and their therapeutic applications.


Assuntos
Nanoestruturas , Ácidos Nucleicos , Ácidos Nucleicos/uso terapêutico , DNA/química , Nanotecnologia/métodos , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Preparações Farmacêuticas
5.
Plant Dis ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129348

RESUMO

Tobacco, Nicotiana tabacum L., is produced largely in China (~1/3 of the global market). In the monsoon summer of 2020, tobacco plant petioles, where axillary buds were removed, became black-rotten, and thick ooze appeared, when squeezed. Lesions encompassed more than half of petiole circumference. Ten tobacco fields (100 plant/field) were investigated in Liuyang, China and 5% disease severity founded in each infected field (Fig. 1A, B, C). Six infected stalks leave of different tobacco were sampled from severe field in Liuyang (N28°21', E113°52') and were surface sterilized (1% sodium hypochlorite for 3 min.), rinsed thrice in sterile distilled water, grounded, and streaked on Luria Bertani agar (LBA). After 24 hours at 28ºC, circular and convex colonies appeared. Hundred colony from ten plates were picked, amplified, and sequenced with the primer 16S-27F/16S-1492R by colony PCR (Lane et al. 1991). 16S rRNA sequence from 100 colony were assembled and fell into two sequences, either similar to Leclercia sp. (86%), or Pantoea sp. (14%). Identification and homology search was done by BLASTn analysis against NCBI and the EzBio Cloud database (Yoon et al. 2017). The Pantoea isolate HN-23 (1,408 bp, MW405831) and the other 16S sequence of 13 Pantoea showed 99.57% identity to the type strain P. endophyitca 596T (PJRT0100022) based on the EzBio Cloud database to identify novel bacteria. Colonies of HN-23 were smooth, translucent, convex with entire margin on LBA, and 1mm and 3mm (diameter), white to yellow, after 24h and 48h (Fig.1 H, I), respectively but white (Fig.1 J, K) on Nutrient Agar (NA). Phenotype of HN-23 (S-1) was performed using API 20E and API ZYM system (bioMérieux, France) and found identical to P. endophytica 596T (Gao et al. 2019). Draft genome of HN-23 (size 4.96Mbp, total Scaffold 79, Scaf N50 218,098bp and Scaf N90 61,041bp) was studied by Illumina sequencing (JAFLWX000000000) and was found to have 98.24% nucleotide identity with the genome of P. endophytica type strain 596. Average nucleotide identity (ANI) values were calculated using Ortho ANIu algorithm (Yoon et al 2017a). HN-23 had 83.89% and 83.65% ANI with P. rodasii LMG26273T and P. dispersa CCUG25232T, respectively (S-2). Six tobacco seedlings (cultivar K326, 30cm height plants grown at greenhouse at 28℃ and 70-80% humidity) were injected by 20µl of culture (109 CFU/ml) of HN-23 and three with dominant species Leclercia sp. HN-7, and reisolated from infected tissues. Pathogenic tissue extract and sterile water were also used as positive and negative control, respectively and experiments were performed in triplicate. After 20h, symptoms of water-soaked decay appeared in the injected leaf axils (Fig. 1D). After 2 days, a severe rot is developed (Fig.1 E). Though, the controls were symptomless (Fig.1 F, G). The bacterium was then isolated from the rotten tissues and identity was confirmed by 16S rDNA sequencing, thus fulfilling Koch's postulates. This species was also reported as endophytes to be isolated from root, stem and leaf of maize planted in diverse parts of China and identified as P. endophytica. To our knowledge, this is the first report of P. endophytica as a plant pathogen, which was firstly isolated from Tobacco planted in southern China.

6.
Arch Microbiol ; 203(3): 1167-1174, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33226466

RESUMO

Chickpea plant root colonizing bacteria Mesorhizobium ciceri Ca181 promotes plant growth and development through symbiotic association with root nodules. The potentially beneficial effects on plants generated due to this bacterium are mineral nutrient solubilization, abiotic stress tolerance, and nitrogen-fixation, though the molecular mechanisms underlying these probiotic capacities are still largely unknown. Hence, this study aims to describe the molecular mechanism of M. ciceri Ca181 in drought stress tolerance and phosphorus solubilization. Here we have developed the transposon inserted mutant library of strain Ca181 and further screened it to identify the phosphorous solubilization and PEG-induced drought stress tolerance defective mutants, respectively. Resultantly, a total of four and three mutants for phosphorous solubilization and drought stress tolerance were screened and identified. Consequently, Southern blot confirmation was done for the cross verification of insertions and stability in the genome. Through the sequencing of each mutant, the interrupted gene was confirmed, and the finding revealed that the production of gluconic acid is necessary for phosphorus solubilization, while otsA, Auc, and Usp genes were involved in the mechanism of drought stress tolerance in M. ciceri Ca181.


Assuntos
Cicer/microbiologia , Mesorhizobium/genética , Raízes de Plantas/microbiologia , Estresse Fisiológico , Secas , Genes Bacterianos/genética , Fixação de Nitrogênio , Fosfatos/metabolismo , Estresse Fisiológico/genética , Simbiose
7.
J Control Release ; 329: 1234-1248, 2021 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-33122001

RESUMO

Conventional agriculture often relies on bulky doses of fertilizers and pesticides that have adversely affected the living beings as well as the ecosystems. As a basic tenet of sustainable agriculture, minimum agrochemicals should be used so that the environment can be protected and various species can be conserved. Further, sustainable agriculture should be a low input system, where the production costs are lower and net returns are higher. The application of nanotechnology in agriculture can significantly enhance the efficiency of agricultural inputs and thus it offers a significant way to maintain sustainable development of agroecosystems via nanoparticles. In this regard, nano-plant growth promoters, nanopesticides, nanofertilizers, nano-herbicides, agrochemical encapsulated nanocarrier systems etc. have been developed for the potential applications in agriculture. These can have great benefits for agriculture, including higher production of crops, inhibition of plant pathogens, removal of unwanted weeds and insects with lesser cost, energy and waste production. However, there are several concerns related to the use of nanoparticles in agriculture. These include the approaches for synthesis, their mechanisms of penetration to applied surfaces and the risks involved. Though, advent of new technologies has significantly improved the synthesis and application of nanomaterials in agriculture, there are many uncertainties regarding nano-synthesis, their way of utilization, uptake and internalization inside the crop cells. Therefore, an elaborate investigation is required for deciphering the engineered nanomaterials, assessing their mechanistic application and agroecological toxicity. Hence, this review is aimed to critically highlight the NPs material application and points towards the vital gaps in the use of nanotechnology for sustainable agriculture.


Assuntos
Ecossistema , Nanopartículas , Agricultura , Agroquímicos , Fertilizantes/análise
8.
Front Microbiol ; 11: 2178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33071999

RESUMO

Soil salinization limits crop growth and yield in agro-ecosystems worldwide by reducing soil health and altering the structure of microbial communities. Salt-tolerant plant growth-promoting rhizobacteria (PGPR) alleviate plant salinity stress. Wild soybean (Glycine soja Sieb. and Zucc.) is unique in agricultural ecosystems owing to its ability to grow in saline-alkali soils and fix atmospheric nitrogen via symbiotic interactions with diverse soil microbes. However, this rhizosphere microbiome and the nodule endosymbionts have not been investigated to identify PGPR. In this study, we investigated the structural and functional rhizosphere microbial communities in saline-alkali soil from the Yellow River Delta and coastal soil in China, as well as wild soybean root nodule endosymbionts. To reveal the composition of the microbial ecosystem, we performed 16S rRNA and nifH gene amplicon sequencing on root nodules and root zones under different environmental conditions. In addition, we used culture-independent methods to examine the root bacterial microbiome of wild soybean. For functional characterization of individual members of the microbiome and their impact on plant growth, we inoculated isolates from the root microbiome with wild soybean and observed nodulation. Sinorhizobium/Ensifer accounted for 97% of the root nodule microbiome, with other enriched members belonging to the phyla Actinobacteria, Bacteroidetes, Chloroflexi, Acidobacteria, and Gemmatimonadetes; the genera Sphingomonas, Microbacterium, Arthrobacter, Nocardioides, Streptomyces, Flavobacterium, Flavisolibacter, and Pseudomonas; and the family Enterobacteriaceae. Compared to saline-alkali soil from the Yellow River Delta, coastal soil was highly enriched for soybean nodules and displayed significant differences in the abundance and diversity of ß-proteobacteria, δ-proteobacteria, Actinobacteria, and Bacteroidetes. Overall, the wild soybean root nodule microbiome was dominated by nutrient-providing Sinorhizobium/Ensifer and was enriched for bacterial genera that may provide salt resistance. Thus, this reductionist experimental approach provides an avenue for future systematic and functional studies of the plant root microbiome.

9.
Molecules ; 25(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33113894

RESUMO

In this work, we present an ecofriendly, non-hazardous, green synthesis of zinc oxide nanoparticles (ZnO NPs) by leaf extract of Crotalaria verrucosa (C. verrucosa). Total phenolic content, total flavonoid and total protein contents of C. verrucosa were determined. Further, synthesized ZnO NPs was characterized by UV-visible spectroscopy (UV-vis), X-ray diffractometer (XRD), Fourier transform infra-red (FTIR) Spectra, transmission electron microscope (TEM), and Dynamic light scattering (DLS) analysis. UV-vis shows peak at 375 nm which is unique to ZnO NPs. XRD analysis demonstrates the hexagonal phase structures of ZnO NPs. FTIR spectra demonstrates the molecules and bondings associated with the synthesized ZnO NPs and assures the role of phytochemical compounds of C. verrucosa in reduction and capping of ZnO NPs. TEM image exhibits that the prepared ZnO NPs is hexagonal shaped and in size ranged between 16 to 38 nm which is confirmed by DLS. Thermo-gravimetric analysis (TGA) was performed to determine the thermal stability of biosynthesized nanoparticles during calcination. The prepared ZnO NPs showed significant antibacterial potentiality against Gram-positive (S. aureus) and Gram-negative (Proteus vulgaris, Klebsiella pneumoniae, and Escherichia coli) pathogenic bacteria and SEM image shows the generalized mechanism of action in bacterial cell after NPs internalization. In addition, NPs are also found to be effective against the studied cancer cell lines for which cytotoxicity was assessed using MTT assay and results demonstrate highest growth of inhibition at the concentration of 100 µg/mL with IC50 value at 7.07 µg/mL for HeLa and 6.30 µg/mL for DU145 cell lines, in contrast to positive control (C. verrucosa leaf extract) with IC50 of 22.30 µg/mL on HeLa cells and 15.72 µg/mL on DU145 cells. Also, DAPI staining was performed in order to determine the effect on nuclear material due to ZnO NPs treatment in the studied cell lines taking leaf extract as positive control and untreated negative control for comparison. Cell migration assay was evaluated to determine the direct influence of NPs on metastasis that is potential suppression capacity of NPs to tumor cell migration. Outcome of the synthesized ZnO NPs using C. verrucosa shows antimicrobial activity against studied microbes, also cytotoxicity, apoptotic mediated DNA damage and antiproliferative potentiality in the studied carcinoma cells and hence, can be further used in biomedical, pharmaceutical and food processing industries as an effective antimicrobial and anti-cancerous agent.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Crotalaria/química , Nanopartículas/química , Folhas de Planta/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/síntese química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Química Verde , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Óxido de Zinco/síntese química
10.
Syst Appl Microbiol ; 43(4): 126089, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32690192

RESUMO

Diversity and taxonomic affiliation of chickpea rhizobia were investigated from Ningxia in north central China and their genomic relationships were compared with those from northwestern adjacent regions (Gansu and Xinjiang). Rhizobia were isolated from root-nodules after trapping by chickpea grown in soils from a single site of Ningxia and typed by IGS PCR-RFLP. Representative strains were phylogenetically analyzed on the basis of the 16S rRNA, housekeeping (atpD, recA and glnII) and symbiosis (nodC and nifH) genes. Genetic differentiation and gene flow were estimated among the chickpea microsymbionts from Ningxia, Gansu and Xinjiang. Fifty chickpea rhizobial isolates were obtained and identified as Mesorhizobium muleiense. Their symbiosis genes nodC and nifH were highly similar (98.4 to 100%) to those of other chickpea microsymbionts, except for one representative strain (NG24) that showed low nifH similarities with all the defined Mesorhizobium species. The rhizobial population from Ningxia was genetically similar to that from Gansu, but different from that in Xinjiang as shown by high chromosomal gene flow/low differentiation with the Gansu population but the reverse with the Xinjiang population. This reveals a biogeographic pattern with two main populations in M. muleiense, the Xinjiang population being chromosomally differentiated from Ningxia-Gansu one. M. muleiense was found as the sole main chickpea-nodulating rhizobial symbiont of Ningxia and it was also found in Gansu sharing alkaline-saline soils with Ningxia. Introduction of chickpea in recently cultivated areas in China seems to select from alkaline-saline soils of M. muleiense that acquired symbiotic genes from symbiovar ciceri.


Assuntos
Cicer/microbiologia , Mesorhizobium/genética , Nódulos Radiculares de Plantas/microbiologia , Simbiose , China , DNA Bacteriano/genética , Fluxo Gênico , Genes Bacterianos/genética , Genes Essenciais/genética , Variação Genética , Genoma Bacteriano/genética , Genótipo , Mesorhizobium/classificação , Mesorhizobium/isolamento & purificação , Mesorhizobium/fisiologia , Filogenia , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo , Simbiose/genética
11.
Biomolecules ; 9(12)2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756942

RESUMO

Abstract:Dickeya sp., a plant pathogen, causing soft rot with strong pectin degradation capacity was taken for the comprehensive analysis of its corresponding biomass degradative system, which has not been analyzed yet. Whole genome sequence analysis of the isolated soft-rotten plant pathogen Dickeya sp. WS52, revealed various coding genes which involved in vegetable stalk degradation-related properties. A total of 122 genes were found to be encoded for putative carbohydrate-active enzymes (CAZy) in Dickeya sp. WS52. The number of pectin degradation-related genes, was higher than that of cellulolytic bacteria as well as other Dickeya spp. strains. The CAZy in Dickeya sp.WS52 contains a complete repertoire of enzymes required for hemicellulose degradation, especially pectinases. In addition, WS52 strain possessed plenty of genes encoding potential ligninolytic relevant enzymes, such as multicopper oxidase, catalase/hydroperoxidase, glutathione S-transferase, and quinone oxidoreductase. Transcriptome analysis revealed that parts of genes encoding lignocellulolytic enzymes were significantly upregulated in the presence of minimal salt medium with vegetable stalks. However, most of the genes were related to lignocellulolytic enzymes, especially pectate lyases and were downregulated due to the slow growth and downregulated secretion systems. The assay of lignocellulolytic enzymes including CMCase and pectinase activities were identified to be more active in vegetable stalk relative to MSM + glucose. However, compared with nutrient LB medium, it needed sufficient nutrient to promote growth and to improve the secretion system. Further identification of enzyme activities of Dickeya sp.WS52 by HPLC confirmed that monosaccharides were produced during degradation of tomato stalk. This identified degradative system is valuable for the application in the lignocellulosic bioenergy industry and animal production.


Assuntos
Proteínas de Bactérias/genética , Capsicum/microbiologia , Gammaproteobacteria/enzimologia , Genoma Bacteriano , Lignina/metabolismo , Doenças das Plantas/microbiologia , Solanum lycopersicum/microbiologia , Proteínas de Bactérias/metabolismo , Catalase/genética , Catalase/metabolismo , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo , Transcriptoma
12.
Microb Cell Fact ; 18(1): 123, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291955

RESUMO

BACKGROUND: Myxococcus xanthus DK1622 is a model system for studying multicellular development, predation, cellular differentiation, and evolution. Furthermore, it is a rich source of novel secondary metabolites and is widely used as heterologous expression host of exogenous biosynthetic gene clusters. For decades, genetic modification of M. xanthus DK1622 has mainly relied on kanamycin and tetracycline selection systems. RESULTS: Here, we introduce an alternative selection system based on chloramphenicol (Cm) to broaden the spectrum of available molecular tools. A chloramphenicol-resistant growth phase and a chloramphenicol-susceptible growth phase before and after chloramphenicol-induction were prepared, and later sequenced to identify specific genes related to chloramphenicol-repercussion and drug-resistance. A total of 481 differentially expressed genes were revealed in chloramphenicol-resistant Cm5_36h and 1920 differentially expressed genes in chloramphenicol-dormant Cm_8h. Moreover, the gene expression profile in the chloramphenicol-dormant strain Cm_8h was quite different from that of Cm5_36 which had completely adapted to Cm, and 1513 differentially expression genes were identified between these two phenotypes. Besides upregulated acetyltransferases, several transporter encoding genes, including ABC transporters, major facilitator superfamily transporters (MFS), resistance-nodulation-cell division (RND) super family transporters and multidrug and toxic compound extrusion family transporters (MATE) were found to be involved in Cm resistance. After the knockout of the most highly upregulated MXAN_2566 MFS family gene, mutant strain DK-2566 was proved to be sensitive to Cm by measuring the growth curve in the Cm-added condition. A plasmid with a Cm resistance marker was constructed and integrated into chromosomes via homologous recombination and Cm screening. The integration efficiency was about 20% at different concentrations of Cm. CONCLUSIONS: This study provides a new antibiotic-based selection system, and will help to understand antibiotic resistance mechanisms in M. xanthus DK1622.


Assuntos
Resistência ao Cloranfenicol/genética , Deleção de Genes , Perfilação da Expressão Gênica , Recombinação Homóloga , Myxococcus xanthus/genética , Antibacterianos/farmacologia , Edição de Genes , Família Multigênica , Myxococcus xanthus/efeitos dos fármacos , Transcriptoma
13.
Cells ; 8(6)2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163575

RESUMO

Two unrecognizable strains of the same bacterial species form a distinct colony boundary. During growth as colonies, Myxococcus xanthus uses multiple factors to establish cooperation between recognized strains and prevent interactions with unrecognized strains of the same species. Here, ΔMXAN_0049 is a mutant strain deficient in immunity for the paired nuclease gene, MXAN_0050, that has a function in the colony-merger incompatibility of Myxococcus xanthus DK1622. With the aim to investigate the factors involved in boundary formation, a proteome and metabolome study was employed. Visualization of the boundary between DK1622 and ΔMXAN_0049 was done scanning electron microscope (SEM), which displayed the presence of many damaged cells in the boundary. Proteome analysis of the DK1622- boundary disclosed many possible proteins, such as cold shock proteins, cell shape-determining protein MreC, along with a few pathways, such as RNA degradation, phenylalanine, tyrosine and tryptophan biosynthesis, and Type VI secretion system (T6SS), which may play major roles in the boundary formation. Metabolomics studies revealed various secondary metabolites that were significantly produced during boundary formation. Overall, the results concluded that multiple factors participated in the boundary formation in M. xanthus, leading to cellular damage that is helpful in solving the mystery of the boundary formation mechanism.


Assuntos
Metabolômica/métodos , Myxococcus xanthus/crescimento & desenvolvimento , Myxococcus xanthus/metabolismo , Proteômica/métodos , Sistemas de Secreção Bacterianos , Contagem de Colônia Microbiana , Regulação para Baixo , Viabilidade Microbiana , Myxococcus xanthus/ultraestrutura , Mapas de Interação de Proteínas , Proteoma/metabolismo , Metabolismo Secundário , Regulação para Cima
14.
Mol Pharm ; 16(3): 1358-1366, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30721074

RESUMO

Functionalized cyclodextrin molecules assemble into a wide variety of superstructures in solution, which are of interest for drug delivery and other nanomaterial and biomaterial applications. Here we use a combined simulation and experimental approach to probe the coassembly of siRNA and cationic cyclodextrin (c-CD) derivatives into a highly stable gene delivery nanostructure. The c-CD form supramolecular structures via interdigitation of their aliphatic tails, analogous to the formation of lipid bilayers and micelles. The native conformation of siRNA is preserved by the encapsulating c-CD superstructure in an extensive hydrogen-bonding network between the positively charged side arms of c-CD and the negatively charged siRNA backbone. The stability of the complexation is confirmed using isothermal titration calorimetry, and the experimental/simulation codesign methodology opens new avenues for creation of highly engineerable gene delivery vectors.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Nanoestruturas/química , RNA Interferente Pequeno/química , beta-Ciclodextrinas/química , Calorimetria , Cátions/química , Estabilidade de Medicamentos , Técnicas de Transferência de Genes , Temperatura Alta , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Eletricidade Estática , Tensoativos/química
15.
Biomolecules ; 8(4)2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30404219

RESUMO

Myxococcus xanthus DK1622 is a rich source of novel secondary metabolites, and it is often used as an expression host of exogenous biosynthetic gene clusters. However, the frequency of obtaining large genome-deletion variants by using traditional strategies is low, and progenies generated by homologous recombination contain irregular deletions. The present study aims to develop an efficient genome-engineering system for this bacterium based on the Cre/loxP system. We first verified the functionality of the native cre system that was integrated into the chromosome with an inducible promoter PcuoA. Then we assayed the deletion frequency of 8-bp-spacer-sequence mutants in loxP by Cre recombinase which was expressed by suicide vector pBJ113 or self-replicative vector pZJY41. It was found that higher guanine content in a spacer sequence had higher deletion frequency, and the self-replicative vector was more suitable for the Cre/loxP system, probably due to the leaky expression of inducible promoter PcuoA. We also inspected the effects of different antibiotics and the native or synthetic cre gene. Polymerase chain reaction (PCR) and sequencing of new genome joints confirmed that the Cre/loxP system was able to delete a 466 kb fragment in M. xanthus. This Cre/loxP-mediated recombination could serve as an alternative genetic manipulation method.


Assuntos
Edição de Genes , Genoma Bacteriano , Integrases/metabolismo , Myxococcus xanthus/genética , Recombinação Genética/genética , Antibacterianos/farmacologia , Sequência de Bases , Cromossomos Bacterianos/genética , Deleção de Genes , Família Multigênica , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Recombinases/metabolismo , Sideróforos/metabolismo
16.
Microbiol Res ; 214: 19-27, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30031478

RESUMO

Site-specific insertion plasmid pVO155 was used to knockout the genes involved in the alternation of host range of strain Bradyrhizobium diazoefficiens USDA 110 from its original determinate-nodule-forming host soybean (Glycine max), to promiscuous and indeterminate-nodule-forming shrubby legume sophora (Sophora flavescens). Symbiotic phenotypes of these mutants inoculated to these two legumes, were compared to those infected by wild-type strain USDA 110. Six genes of the total fourteen Tn5 transposon mutated genes were broken using the pVO155 plasmid. Both Tn5 and pVO155-inserted mutants could nodulate S. flavescens with different morphologies of low-efficient indeterminate nodules. One to several rod or irregular bacteroids, containing different contents of poly-ß-hydroxybutyrate or polyphosphate were found within the symbiosomes in nodulated cells of S. flavescens infected by the pVO155-inserted mutants. Moreover, none of bacteroids were observed in the pseudonodules of S. flavescens, infected by wild-type strain USDA 110. These mutants had the nodulation ability with soybean but the symbiotic efficiency reduced to diverse extents. These findings enlighten the complicated interactions between rhizobia and legumes, i. e., mutation of genes involved in metabolic pathways, transporters, chemotaxis and mobility could alter the rhizobial entry and development of the bacteroid inside the nodules of a new host legume.


Assuntos
Bradyrhizobium/isolamento & purificação , Bradyrhizobium/fisiologia , Sophora/microbiologia , Simbiose , Bradyrhizobium/genética , Elementos de DNA Transponíveis , Deleção de Genes , Especificidade de Hospedeiro , Mutagênese Insercional , Nodulação
17.
World J Microbiol Biotechnol ; 33(7): 137, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28585173

RESUMO

Epothilones are cytotoxic macrolactones having auspicious anti-tumorous activities, but merely produced by rare Sorangium strains. Here, we have focused on the epothilone gene cluster from special niche bacterial strain, S. cellulosum So0157-2. Therefore, we have isolated a high pH tolerant S. cellulosum strain So0157-2 and characterized the epothilones gene cluster and its flanks by cosmid/fosmid libraries preparation and sequencing. The assembly spanned 94,459 bp and consisted of 56,019 bp core region. Remarkably, the core as well as upstream 420 bp and downstream 315 bp were highly conserved, while further neighboring regions varied extremely. Transposase traces were identified near the core of clusters, supporting that the transposon-mediated transgenesis is a naturally evolved strategy for the cluster's dissemination. A predicted neighboring esterase gene was identified as a potential epothilone-resistance gene preventing self-toxicity. Novel modification or regulatory genes, a multi-position-cyclo releasing gene and their relationship with corresponding analogs were identified in strain So0157-2. These findings open the door to discover additional, naturally evolved epothilone-related genes for significant applications in industrial as well as clinical sector.


Assuntos
Proteínas de Bactérias/genética , Clonagem Molecular/métodos , Epotilonas/biossíntese , Myxococcales/isolamento & purificação , Epotilonas/genética , Esterases/genética , Evolução Molecular , Tamanho do Genoma , Biblioteca Genômica , Família Multigênica , Myxococcales/genética , Myxococcales/metabolismo , Análise de Sequência de DNA/métodos , Transposases/genética
18.
J Basic Microbiol ; 56(1): 14-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26377641

RESUMO

In an effort to obtain reliable, alkali-tolerant, and symbiotically efficient rhizobial strains, 54 indigenous rhizobial isolates were obtained from root nodules of chickpea grown in alkaline soil of 5 different agricultural locations in North-West Indo Gangetic Plains (NW-IGP). Of these, 16 most symbiotically effective isolates were selected for polyphasic analysis (pH stress, salt tolerance, and genetic characterization). All the selected isolates were able to tolerate the high alkaline pH. Among them, CPN1, CPN8, and CPN32 grew well at pH 11.0. High pH-induced proteins were explored by SDS-PAGE assay. Identification and genetic characterization of isolates was done by 16S rRNA gene sequencing, RNA polymerase subunit-B (rpoB) and symbiotic genes (nodC and nifH). The study revealed diverse symbiotically efficient alkalotolerant chickpea nodulating rhizobial strains from NW-IGP. This study has thus contributed a valuable genetic pool of isolates that can potentially be used to increase chickpea production in these soil types.


Assuntos
Cicer/microbiologia , Rhizobium/isolamento & purificação , Agricultura , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Temperatura Alta , Concentração de Íons de Hidrogênio , Índia , RNA Ribossômico 16S/genética , Rhizobium/genética , Rhizobium/crescimento & desenvolvimento , Rhizobium/fisiologia , Nódulos Radiculares de Plantas/microbiologia , Salinidade , Tolerância ao Sal , Microbiologia do Solo , Simbiose/fisiologia
19.
Biophys J ; 105(12): 2820-31, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24359754

RESUMO

We studied the structure and mechanical properties of DNA i-motif nanowires by means of molecular dynamics computer simulations. We built up to 230 nm-long nanowires, based on a repeated TC5 sequence from crystallographic data, fully relaxed and equilibrated in water. The unusual C⋅C(+) stacked structure, formed by four ssDNA strands arranged in an intercalated tetramer, is here fully characterized both statically and dynamically. By applying stretching, compression, and bending deformations with the steered molecular dynamics and umbrella sampling methods, we extract the apparent Young's and bending moduli of the nanowire, as well as estimates for the tensile strength and persistence length. According to our results, the i-motif nanowire shares similarities with structural proteins, as far as its tensile stiffness, but is closer to nucleic acids and flexible proteins, as far as its bending rigidity is concerned. Furthermore, thanks to its very thin cross section, the apparent tensile toughness is close to that of a metal. Besides their yet to be clarified biological significance, i-motif nanowires may qualify as interesting candidates for nanotechnology templates, due to such outstanding mechanical properties.


Assuntos
DNA de Cadeia Simples/química , Simulação de Dinâmica Molecular , Nanofios/química , Sequência de Bases , Dados de Sequência Molecular , Motivos de Nucleotídeos
20.
Bioinformation ; 8(22): 1111-3, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23251046

RESUMO

Environmental pollutants containing halogenated organic compounds e.g. haloacid, can cause a plethora of health problems. The structural and functional analyses of the gene responsible of their degradation are an important aspect for environmental studies and are important to human well-being. It has been shown that some haloacids are toxic and mutagenic. Microorganisms capable of degrading these haloacids can be found in the natural environment. One of these, a soil-borne Burkholderia mallei posses the ability to grow on monobromoacetate (MBA). This bacterium produces a haloacid dehalogenase that allows the cell to grow on MBA, a highly toxic and mutagenic environmental pollutant. For the structural and functional analysis, a 346 amino acid encoding protein sequence of haloacid dehalogenase is retrieve from NCBI data base. Primary and secondary structure analysis suggested that the high percentage of helices in the structure makes the protein more flexible for folding, which might increase protein interactions. The consensus protein sub-cellular localization predictions suggest that dehalogenase protein is a periplasmic protein 3D2GO server, suggesting that it is mainly employed in metabolic process followed by hydrolase activity and catalytic activity. The tertiary structure of protein was predicted by homology modeling. The result suggests that the protein is an unstable protein which is also an important characteristic of active enzyme enabling them to bind various cofactors and substrate for proper functioning. Validation of 3D structure was done using Ramachandran plot ProsA-web and RMSD score. This predicted information will help in better understanding of mechanism underlying haloacid dehalogenase encoding protein and its evolutionary relationship.

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