Base de dados : MEDLINE
Pesquisa : G05.728.390 [Categoria DeCS]
Referências encontradas : 5161 [refinar]
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[PMID]:29408405
[Au] Autor:Wang H; Park BS; Lim WA; Ki JS
[Ad] Endereço:Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea.
[Ti] Título:CpMCA, a novel metacaspase gene from the harmful dinoflagellate Cochlodinium polykrikoides and its expression during cell death.
[So] Source:Gene;651:70-78, 2018 Apr 20.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Metacaspases (MCAs) are cysteine proteases that share sequence homology with caspases, and may play roles in programmed cell death (PCD). In the present study, we identified a novel MCA gene (CpMCA) from the red tide dinoflagellate Cochlodinium polykrikoides, and examined its molecular characteristics and gene expression in response to algicide-induced cell death. CpMCA cDNA is 1164 bp in length, containing a dinoflagellate spliced leader sequence (dinoSL), an 879-bp open reading frame (ORF), which codes for a 293-aa protein, and a poly (A) tail. Multi-sequence comparison indicated that CpMCA belongs to type I MCA, but it has a different structure at the N-terminal. Phylogenetic analysis showed that C. polykrikoides may have acquired the MCA gene from bacteria by means of horizontal gene transfer (HGT). In addition, expressions of CpMCA significantly increased following exposure to the common algicides copper sulfate and oxidizing chlorine, which trigger cell death in dinoflagellates, suggesting that CpMCA may be involved in cell death.
[Mh] Termos MeSH primário: Caspases/genética
Dinoflagelados/genética
[Mh] Termos MeSH secundário: Morte Celular/efeitos dos fármacos
Morte Celular/genética
DNA Complementar
DNA de Protozoário
Dinoflagelados/efeitos dos fármacos
Dinoflagelados/enzimologia
Expressão Gênica
Transferência Genética Horizontal
Genes Bacterianos
Genes de Protozoários
Herbicidas/farmacologia
Filogenia
Análise de Sequência de DNA
Transcrição Genética/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (DNA, Protozoan); 0 (Herbicides); EC 3.4.22.- (Caspases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE


  2 / 5161 MEDLINE  
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[PMID]:29179671
[Au] Autor:Hudaiberdiev S; Shmakov S; Wolf YI; Terns MP; Makarova KS; Koonin EV
[Ad] Endereço:National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD, USA.
[Ti] Título:Phylogenomics of Cas4 family nucleases.
[So] Source:BMC Evol Biol;17(1):232, 2017 Nov 28.
[Is] ISSN:1471-2148
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: The Cas4 family endonuclease is a component of the adaptation module in many variants of CRISPR-Cas adaptive immunity systems. Unlike most of the other Cas proteins, Cas4 is often encoded outside CRISPR-cas loci (solo-Cas4) and is also found in mobile genetic elements (MGE-Cas4). RESULTS: As part of our ongoing investigation of CRISPR-Cas evolution, we explored the phylogenomics of the Cas4 family. About 90% of the archaeal genomes encode Cas4 compared to only about 20% of the bacterial genomes. Many archaea encode both the CRISPR-associated form (CAS-Cas4) and solo-Cas4, whereas in bacteria, this combination is extremely rare. The solo-cas4 genes are over-represented in environmental bacteria and archaea with small genomes that typically lack CRISPR-Cas, suggesting that Cas4 could perform uncharacterized defense or repair functions in these microbes. Phylogenomic analysis indicates that both the CRISPR-associated cas4 genes are often transferred horizontally but almost exclusively, as part of the adaptation module. The evolutionary integrity of the adaptation module sharply contrasts the rampant shuffling of CRISPR-cas modules whereby a given variant of the adaptation module can combine with virtually any effector module. The solo-cas4 genes evolve primarily via vertical inheritance and are subject only to occasional horizontal transfer. The selection pressure on cas4 genes does not substantially differ between CAS-Cas4 and solo-cas4, and is close to the genomic median. Thus, cas4 genes, similarly to cas1 and cas2, evolve similarly to 'regular' microbial genes involved in various cellular functions, showing no evidence of direct involvement in virus-host arms races. A notable feature of the Cas4 family evolution is the frequent recruitment of cas4 genes by various mobile genetic elements (MGE), particularly, archaeal viruses. The functions of Cas4 in these elements are unknown and potentially might involve anti-defense roles. CONCLUSIONS: Unlike most of the other Cas proteins, Cas4 family members are as often encoded by stand-alone genes as they are incorporated in CRISPR-Cas systems. In addition, cas4 genes were repeatedly recruited by MGE, perhaps, for anti-defense functions. Experimental characterization of the solo and MGE-encoded Cas4 nucleases is expected to reveal currently uncharacterized defense and anti-defense systems and their interactions with CRISPR-Cas systems.
[Mh] Termos MeSH primário: Sistemas CRISPR-Cas/genética
Endonucleases/genética
Genômica
Família Multigênica
[Mh] Termos MeSH secundário: Archaea/enzimologia
Archaea/genética
Bactérias/enzimologia
Bactérias/genética
Sequência de Bases
Elementos de DNA Transponíveis/genética
Transferência Genética Horizontal/genética
Loci Gênicos
Genoma Arqueal
Genoma Bacteriano
Filogenia
Seleção Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA Transposable Elements); EC 3.1.- (Endonucleases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE
[do] DOI:10.1186/s12862-017-1081-1


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[PMID]:28461122
[Au] Autor:Werisch M; Berger U; Berendonk TU
[Ad] Endereço:Technische Universität Dresden, Department of Forest Sciences, Institute of Forest Growth and Forest Computer Sciences, Tharandt 01735, Germany. Electronic address: martin.werisch@tu-dresden.de.
[Ti] Título:Conjugative plasmids enable the maintenance of low cost non-transmissible plasmids.
[So] Source:Plasmid;91:96-104, 2017 May.
[Is] ISSN:1095-9890
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Some plasmids can be transferred by conjugation to other bacterial hosts. But almost half of the plasmids are non-transmissible. These plasmid types can only be transmitted to the daughter cells of their host after bacterial fission. Previous studies suggest that non-transmissible plasmids become extinct in the absence of selection of their encoded traits, as plasmid-free bacteria are more competitive. Here, we aim to identify mechanisms that enable non-transmissible plasmids to persist, even if they are not beneficial. For this purpose, an individual-based model for plasmid population dynamics was set up and carefully tested for structural consistency and plausibility. Our results demonstrate that non-transmissible plasmids can be stably maintained in a population, even if they impose a substantial burden on their host cells growth. A prerequisite is the co-occurrence of an incompatible and costly conjugative plasmid type, which indirectly facilitates the preservation of the non-transmissible type. We suggest that this constellation might be considered as a potential mechanism maintaining plasmids and associated antibiotic resistances. It should be investigated in upcoming laboratory experiments.
[Mh] Termos MeSH primário: Bactérias/genética
Conjugação Genética
Regulação Bacteriana da Expressão Gênica
Transferência Genética Horizontal
Modelos Estatísticos
Plasmídeos/química
[Mh] Termos MeSH secundário: Bactérias/metabolismo
Simulação por Computador
Aptidão Genética
Plasmídeos/metabolismo
Seleção Genética
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE


  4 / 5161 MEDLINE  
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[PMID]:28461121
[Au] Autor:Hall JPJ; Brockhurst MA; Dytham C; Harrison E
[Ad] Endereço:Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
[Ti] Título:The evolution of plasmid stability: Are infectious transmission and compensatory evolution competing evolutionary trajectories?
[So] Source:Plasmid;91:90-95, 2017 May.
[Is] ISSN:1095-9890
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Conjugative plasmids are widespread and play an important role in bacterial evolution by accelerating adaptation through horizontal gene transfer. However, explaining the long-term stability of plasmids remains challenging because segregational loss and the costs of plasmid carriage should drive the loss of plasmids though purifying selection. Theoretical and experimental studies suggest two key evolutionary routes to plasmid stability: First, the evolution of high conjugation rates would allow plasmids to survive through horizontal transmission as infectious agents, and second, compensatory evolution to ameliorate the cost of plasmid carriage can weaken purifying selection against plasmids. How these two evolutionary strategies for plasmid stability interact is unclear. Here, we summarise the literature on the evolution of plasmid stability and then use individual based modelling to investigate the evolutionary interplay between the evolution of plasmid conjugation rate and cost amelioration. We find that, individually, both strategies promote plasmid stability, and that they act together to increase the likelihood of plasmid survival. However, due to the inherent costs of increasing conjugation rate, particularly where conjugation is unlikely to be successful, our model predicts that amelioration is the more likely long-term solution to evolving stable bacteria-plasmid associations. Our model therefore suggests that bacteria-plasmid relationships should evolve towards lower plasmid costs that may forestall the evolution of highly conjugative, 'infectious' plasmids.
[Mh] Termos MeSH primário: Bactérias/genética
Conjugação Genética
Regulação Bacteriana da Expressão Gênica
Transferência Genética Horizontal
Modelos Estatísticos
Plasmídeos/química
[Mh] Termos MeSH secundário: Bactérias/metabolismo
Evolução Biológica
Cromossomos Bacterianos/química
Cromossomos Bacterianos/metabolismo
Aptidão Genética
Loci Gênicos
Mutagênese Insercional
Plasmídeos/metabolismo
Seleção Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE


  5 / 5161 MEDLINE  
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[PMID]:28456703
[Au] Autor:Bi W; Li B; Song J; Hong Y; Zhang X; Liu H; Lu H; Zhou T; Cao J
[Ad] Endereço:School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province, China.
[Ti] Título:Antimicrobial susceptibility and mechanisms of fosfomycin resistance in extended-spectrum ß-lactamase-producing Escherichia coli strains from urinary tract infections in Wenzhou, China.
[So] Source:Int J Antimicrob Agents;50(1):29-34, 2017 Jul.
[Is] ISSN:1872-7913
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Fosfomycin in combination with various antibiotics represents an excellent clinically efficacious regimen for the treatment of urinary tract infections (UTIs) caused by extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli. Underlying mechanisms of fosfomycin resistance remain largely uncharacterised. To investigate the antibacterial efficacy of fosfomycin against ESBL-producing E. coli, 356 non-repetitive ESBL-producing E. coli clinical isolates were collected from urine specimens from patients with UTI in Wenzhou, China, from January 2011 to December 2015. Antimicrobial sensitivity testing indicated that 6.7% (24/356) of the ESBL-producing E. coli strains were resistant to fosfomycin. The fosA3 gene encoding a fosfomycin-modifying enzyme was detected in 20 isolates by PCR and sequencing, alone or in combination with other ESBL determinants. Conjugation experiments and Southern blotting demonstrated that 70% (14/20) of the fosA3-positive isolates possessed transferable plasmids (ca. 54.2 kb) co-harbouring the ESBL resistance gene bla and the fosfomycin resistance gene fosA3. Among the four fosfomycin-resistant fosA3-negative E. coli isolates, three contained amino acid substitutions (Ile28Asn and Phe30Leu in MurA and Leu297Phe in GlpT). The results indicate that presence of the fosA3 gene is the primary mechanism of fosfomycin resistance in ESBL-producing E. coli isolates in Wenzhou, China. In addition, a plasmid (ca. 54.2 kb) co-harbouring fosA3 and bla genes is horizontally transferable. Furthermore, a low degree of homology in the fosfomycin-resistant E. coli was confirmed using multilocus sequence typing (MLST), suggesting that there is no obvious phenomenon of clonal dissemination.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Farmacorresistência Bacteriana
Infecções por Escherichia coli/microbiologia
Escherichia coli/efeitos dos fármacos
Fosfomicina/farmacologia
Infecções Urinárias/microbiologia
beta-Lactamases/secreção
[Mh] Termos MeSH secundário: Southern Blotting
China
Conjugação Genética
Escherichia coli/enzimologia
Escherichia coli/isolamento & purificação
Proteínas de Escherichia coli/genética
Transferência Genética Horizontal
Seres Humanos
Testes de Sensibilidade Microbiana
Plasmídeos/análise
Reação em Cadeia da Polimerase
Análise de Sequência de DNA
beta-Lactamases/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Escherichia coli Proteins); 0 (FosA(3) protein, E coli); 2N81MY12TE (Fosfomycin); EC 3.5.2.6 (beta-Lactamases)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170501
[St] Status:MEDLINE


  6 / 5161 MEDLINE  
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[PMID]:29368868
[Au] Autor:Zakharov IA
[Ti] Título:[Horizontal gene transfer into the genomes of insects].
[So] Source:Genetika;52(7):804-9, 2016 Jul.
[Is] ISSN:0016-6758
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Horizontal gene transfer (HGT) is widespread in the world of prokaryotes, but the examples of this phenomenon among multicellular animals, particularly insects, are few. This review examines the transfer of genetic material to the nuclear genomes of insects from the mitochondrial genome (intracellular HGT), as well as from the genomes of viruses, bacteria, fungi, and unrelated insects. In most cases, the mechanisms of this transfer are unknown. Many pro- and eukaryotic genes that moved through the HGT are expressed in the insect genome and in some cases can provide the evolutionary innovations that are considered as aromorphoses.
[Mh] Termos MeSH primário: Evolução Molecular
Transferência Genética Horizontal/fisiologia
Insetos/genética
[Mh] Termos MeSH secundário: Animais
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE


  7 / 5161 MEDLINE  
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[PMID]:28460114
[Au] Autor:Reynolds HT; Slot JC; Divon HH; Lysøe E; Proctor RH; Brown DW
[Ad] Endereço:Department of Plant Pathology, The Ohio State University, Columbus, OH.
[Ti] Título:Differential Retention of Gene Functions in a Secondary Metabolite Cluster.
[So] Source:Mol Biol Evol;34(8):2002-2015, 2017 Aug 01.
[Is] ISSN:1537-1719
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In fungi, distribution of secondary metabolite (SM) gene clusters is often associated with host- or environment-specific benefits provided by SMs. In the plant pathogen Alternaria brassicicola (Dothideomycetes), the DEP cluster confers an ability to synthesize the SM depudecin, a histone deacetylase inhibitor that contributes weakly to virulence. The DEP cluster includes genes encoding enzymes, a transporter, and a transcription regulator. We investigated the distribution and evolution of the DEP cluster in 585 fungal genomes and found a wide but sporadic distribution among Dothideomycetes, Sordariomycetes, and Eurotiomycetes. We confirmed DEP gene expression and depudecin production in one fungus, Fusarium langsethiae. Phylogenetic analyses suggested 6-10 horizontal gene transfers (HGTs) of the cluster, including a transfer that led to the presence of closely related cluster homologs in Alternaria and Fusarium. The analyses also indicated that HGTs were frequently followed by loss/pseudogenization of one or more DEP genes. Independent cluster inactivation was inferred in at least four fungal classes. Analyses of transitions among functional, pseudogenized, and absent states of DEP genes among Fusarium species suggest enzyme-encoding genes are lost at higher rates than the transporter (DEP3) and regulatory (DEP6) genes. The phenotype of an experimentally-induced DEP3 mutant of Fusarium did not support the hypothesis that selective retention of DEP3 and DEP6 protects fungi from exogenous depudecin. Together, the results suggest that HGT and gene loss have contributed significantly to DEP cluster distribution, and that some DEP genes provide a greater fitness benefit possibly due to a differential tendency to form network connections.
[Mh] Termos MeSH primário: Alcadienos/metabolismo
Compostos de Epóxi/metabolismo
Álcoois Graxos/metabolismo
Genoma Fúngico/genética
Família Multigênica/genética
[Mh] Termos MeSH secundário: Ascomicetos/genética
Bases de Dados de Ácidos Nucleicos
Evolução Molecular
Proteínas Fúngicas/genética
Fusarium/genética
Perfilação da Expressão Gênica/métodos
Regulação Fúngica da Expressão Gênica/genética
Transferência Genética Horizontal/genética
Filogenia
Metabolismo Secundário/genética
Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkadienes); 0 (Epoxy Compounds); 0 (Fatty Alcohols); 0 (Fungal Proteins); 139508-73-9 (depudecin)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180201
[Lr] Data última revisão:
180201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1093/molbev/msx145


  8 / 5161 MEDLINE  
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[PMID]:29176894
[Au] Autor:Levillain F; Poquet Y; Mallet L; Mazères S; Marceau M; Brosch R; Bange FC; Supply P; Magalon A; Neyrolles O
[Ad] Endereço:Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France.
[Ti] Título:Horizontal acquisition of a hypoxia-responsive molybdenum cofactor biosynthesis pathway contributed to Mycobacterium tuberculosis pathoadaptation.
[So] Source:PLoS Pathog;13(11):e1006752, 2017 Nov.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The unique ability of the tuberculosis (TB) bacillus, Mycobacterium tuberculosis, to persist for long periods of time in lung hypoxic lesions chiefly contributes to the global burden of latent TB. We and others previously reported that the M. tuberculosis ancestor underwent massive episodes of horizontal gene transfer (HGT), mostly from environmental species. Here, we sought to explore whether such ancient HGT played a part in M. tuberculosis evolution towards pathogenicity. We were interested by a HGT-acquired M. tuberculosis-specific gene set, namely moaA1-D1, which is involved in the biosynthesis of the molybdenum cofactor. Horizontal acquisition of this gene set was striking because homologues of these moa genes are present all across the Mycobacterium genus, including in M. tuberculosis. Here, we discovered that, unlike their paralogues, the moaA1-D1 genes are strongly induced under hypoxia. In vitro, a M. tuberculosis moaA1-D1-null mutant has an impaired ability to respire nitrate, to enter dormancy and to survive in oxygen-limiting conditions. Conversely, heterologous expression of moaA1-D1 in the phylogenetically closest non-TB mycobacterium, Mycobacterium kansasii, which lacks these genes, improves its capacity to respire nitrate and grants it with a marked ability to survive oxygen depletion. In vivo, the M. tuberculosis moaA1-D1-null mutant shows impaired survival in hypoxic granulomas in C3HeB/FeJ mice, but not in normoxic lesions in C57BL/6 animals. Collectively, our results identify a novel pathway required for M. tuberculosis resistance to host-imposed stress, namely hypoxia, and provide evidence that ancient HGT bolstered M. tuberculosis evolution from an environmental species towards a pervasive human-adapted pathogen.
[Mh] Termos MeSH primário: Coenzimas/biossíntese
Transferência Genética Horizontal
Metaloproteínas/biossíntese
Mycobacterium tuberculosis/genética
Mycobacterium tuberculosis/metabolismo
Oxigênio/metabolismo
Tuberculose/microbiologia
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Feminino
Regulação Bacteriana da Expressão Gênica
Seres Humanos
Hipóxia/metabolismo
Hipóxia/microbiologia
Camundongos
Camundongos Endogâmicos C57BL
Mycobacterium/genética
Mycobacterium/metabolismo
Nitratos/metabolismo
Pteridinas
Tuberculose/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Coenzymes); 0 (Metalloproteins); 0 (Nitrates); 0 (Pteridines); 73508-07-3 (molybdenum cofactor); S88TT14065 (Oxygen)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180109
[Lr] Data última revisão:
180109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006752


  9 / 5161 MEDLINE  
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[PMID]:28459967
[Au] Autor:Blanchard LS; Monin A; Ouertani H; Touaibia L; Michel E; Buret F; Simonet P; Morris CE; Demanèche S
[Ad] Endereço:Université de Lyon, École Centrale de Lyon, Laboratoire Ampére (CNRS UMR5005), Environmental Microbial Genomics, 69134 Ecully Cedex, France.
[Ti] Título:Survival and electrotransformation of Pseudomonas syringae strains under simulated cloud-like conditions.
[So] Source:FEMS Microbiol Ecol;93(5), 2017 05 01.
[Is] ISSN:1574-6941
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:To diversify their genetic material, and thereby allow adaptation to environmental disturbances and colonization of new ecological niches, bacteria use various evolutionary processes, including the acquisition of new genetic material by horizontal transfer mechanisms such as conjugation, transduction and transformation. Electrotransformation mediated by lightning-related electrical phenomena may constitute an additional gene-transfer mechanism occurring in nature. The presence in clouds of bacteria such as Pseudomonas syringae capable of forming ice nuclei that lead to precipitation, and that are likely to be involved in triggering lightning, led us to postulate that natural electrotransformation in clouds may contribute to the adaptive potential of these bacteria. Here, we quantify the survival rate of 10 P. syringae strains in liquid and icy media under such electrical pulses and their capacity to acquire exogenous DNA. In comparison to two other bacteria (Pseudomonas sp. N3 and Escherichia coli TOP10), P. syringae CC0094 appears to be best adapted for survival and for genetic electrotransformation under these conditions, which suggests that this bacterium would be able to survive and to get a boost in its adaptive potential while being transported in clouds and falling back to Earth with precipitation from storms.
[Mh] Termos MeSH primário: Adaptação Fisiológica/genética
Transferência Genética Horizontal/genética
Pseudomonas syringae/genética
Pseudomonas syringae/metabolismo
[Mh] Termos MeSH secundário: Evolução Biológica
DNA Bacteriano/metabolismo
Estimulação Elétrica
Eletroporação/métodos
Escherichia coli/genética
Gelo
Relâmpago
Pseudomonas syringae/crescimento & desenvolvimento
Tempo (Meteorologia)
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Ice)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171224
[Lr] Data última revisão:
171224
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1093/femsec/fix057


  10 / 5161 MEDLINE  
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[PMID]:27774436
[Au] Autor:Huang J; Ma J; Shang K; Hu X; Liang Y; Li D; Wu Z; Dai L; Chen L; Wang L
[Ad] Endereço:Laboratory of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
[Ti] Título:Evolution and Diversity of the Antimicrobial Resistance Associated Mobilome in : A Probable Mobile Genetic Elements Reservoir for Other Streptococci.
[So] Source:Front Cell Infect Microbiol;6:118, 2016.
[Is] ISSN:2235-2988
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:is a previously neglected, newly emerging multidrug-resistant zoonotic pathogen. Mobile genetic elements (MGEs) play a key role in intra- and interspecies horizontal transfer of antimicrobial resistance (AMR) determinants. Although, previous studies showed the presence of several MGEs, a comprehensive analysis of AMR-associated mobilome as well as their interaction and evolution has not been performed. In this study, we presented the AMR-associated mobilome and their insertion hotspots in . Integrative conjugative elements (ICEs), prophages and tandem MGEs were located at different insertion sites, while 86% of the AMR-associated MGEs were inserted at and loci. Comprehensive analysis of insertions at and loci among four pathogenic species ( , and ) revealed the existence of different groups of MGEs, including Tn5252, ICE 1108, and TnGBS2 groups ICEs, Φm46.1 group prophage, ICE_ICE and ICE_prophage tandem MGEs. Comparative ICE genomics of ICE 2603 family revealed that module exchange and acquisition/deletion were the main mechanisms in MGEs' expansion and evolution. Furthermore, the observation of tandem MGEs reflected a novel mechanism for MGE diversity. Moreover, an competition assay showed no visible fitness cost was observed between different MGE-carrying isolates and a conjugation assay revealed the transferability of ICE 2603 family of ICEs. Our statistics further indicated that the prevalence and diversity of MGEs in is much greater than in other three species which prompted our hypothesis that is probably a MGEs reservoir for other streptococci. In conclusion, our results showed that acquisition of MGEs confers not only its capability as a multidrug resistance pathogen, but also represents a paradigm to study the modular evolution and matryoshkas of MGEs.
[Mh] Termos MeSH primário: Farmacorresistência Bacteriana
Sequências Repetitivas Dispersas
Streptococcus/efeitos dos fármacos
Streptococcus/genética
[Mh] Termos MeSH secundário: Conjugação Genética
Transferência Genética Horizontal
Loci Gênicos
Recombinação Genética
Análise de Sequência de DNA
Streptococcus/crescimento & desenvolvimento
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171224
[Lr] Data última revisão:
171224
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE



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