Evolution of gentamicin and arsenite resistance acquisition in Ralstonia pickettii water isolates

ABSTRACT In Ralstonia pickettii PKO1, a denitrifying toluene oxidizer that carries a toluene-3-monooxygenase (T3MO) pathway, the biodegradation of toluene and trichloroethylene (TCE) by the organism is induced by TCE at high concentrations. In this study, the effect of TCE preexposure was studied in the context of bacterial protective response to TCE-mediated toxicity in this organism. The results of TCE degradation experiments showed that cells induced by TCE at 110 mg/liter were more tolerant to TCE-mediated stress than were those induced by TCE at lower concentrations, indicating an ability of PKO1 to adapt to TCE-mediated stress. To characterize the bacterial protective response to TCE-mediated stress, the effect of TCE itself (solvent stress) was isolated from TCE degradation-dependent stress (toxic intermediate stress) in the subsequent chlorinated ethylene toxicity assays with both nondegradable tetrachloroethylene and degradable TCE. The results of the toxicity assays showed that TCE preexposure led to an increase in tolerance to TCE degradation-dependent stress rather than to solvent stress. The possibility that such tolerance was selected by TCE degradation-dependent stress during TCE preexposure was ruled out because a similar extent of tolerance was observed in cells that were induced by toluene, whose metabolism does not produce any toxic products. These findings suggest that the adaptation of TCE-induced cells to TCE degradation-dependent stress was caused by the combined effects of solvent stress response and T3MO pathway expression.

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Draft Genome Sequences of Two Ralstonia pickettii Strains with Different Aminoglycoside Resistance Phenotypes

Genome Announcements ◽

10.1128/genomea.01257-16 ◽

2016 ◽

Vol 4 (6) ◽

Cited By ~ 2

Author(s):

Ivone Vaz-Moreira ◽

Javier Tamames ◽

José Luis Martínez ◽

Célia M. Manaia

Keyword(s):

Draft Genome ◽

Selective Medium ◽

Genome Sequences ◽

Aminoglycoside Resistance ◽

Ralstonia Pickettii ◽

Hospital Effluent

The genomes of two Ralstonia pickettii strains (H2Cu2 and H2Cu5), isolated from hospital effluent in a selective medium containing CuSO 4, were sequenced. They presented MICs of >256 and 6 µg/ml for the aminoglycoside gentamicin, respectively. The 5.2-Mb draft genomes have 40 contigs for strain H2Cu2 and 113 for H2Cu5.

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Bakteri Agens Hayati Potensial terhadap Patogen Penting pada Padi

Jurnal Fitopatologi Indonesia ◽

10.14692/jfi.16.1.37-48 ◽

2020 ◽

Vol 16 (1) ◽

pp. 37-48

Author(s):

Ratna Sari Dewi ◽

Giyanto Giyanto ◽

Meity Suradji Sinaga ◽

Dadang Dadang ◽

Bambang Nuryanto

Keyword(s):

Bacillus Subtilis ◽

Rhizoctonia Solani ◽

Pseudomonas Fluorescens ◽

Pyricularia Oryzae ◽

Burkholderia Glumae ◽

Streptomyces Sp ◽

Ralstonia Pickettii

Saat ini teknologi pengendalian hayati penyakit utama padi terus berkembang. Dalam pengembangan teknologi pengendalian hayati, mekanisme penghambatan patogen dalam perkembangan penyakit pada suatu populasi tumbuhan dalam area tertentu menjadi hal yang penting. Penelitian bertujuan mendapatkan bakteri agens hayati potensial dalam pengendalian penyakit penting padi di antaranya yang disebabkan Pyricularia oryzae, Xanthomnas oryzae pv. oryzae, Rhizoctonia solani, Burkholderia glumae, dan Drechlera oryzae, berdasarkan mekanisme antagonisme, kemampuan menginduksi ketahanan dan mendukung kebugaran tanaman, serta kompatibilitas antaragens hayati. Ralstonia pickettii TT47, Pseudomonas fluorescens P12, Chromobacterium sp. T51118, Bacillus subtilis 451 dan 154, serta Streptomyces sp. T51105 dibuktikan memiliki mekanisme antibiosis dengan menghasilkan metabolit sekunder dan senyawa volatil. Berdasarkan uji produksi enzim kitinolitik Chromobacterium sp. dan Streptomyces sp. memiliki mekanisme lisis. Aktivitas antibiotik R. pickettii dan P. fluorescens tergolong kuat terhadap P. oryzae dengan penekanan secara berurutan sebesar 79.68% dan 77.59% pada uji biakan ganda. Penekanan pertumbuhan miselium P. oryzae dan R. solani pada uji volatil mencapai 100% oleh Chromobacterium sp. Semua agens hayati umumnya mampu menginduksi ketahanan dan mendukung kebugaran tanaman. Uji kompatibilitas menunjukan R. pickettii, P. fluorescens, dan Chromobacterium sp. bersifat kompatibel. Dari hasil penelitian diperoleh tiga bakteri agens hayati dengan kategori unggul, yaitu P. fluorescens P12, R. pickettii TT47, dan Chromobacterium sp. T51118. Ketiganya mampu menekan pertumbuhan patogen, menginduksi ketahanan dan mendukung kebugaran tanaman, memiliki patogen sasaran yang lebih beragam, serta bersifat kompatibel.

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Genotypic and phylogenetic characterisation of a clinical Ralstonia pickettii strain carrying two novel OXA allelic variants, blaOXA-898 and blaOXA-899, isolated from a bloodstream infection in China

Journal of Global Antimicrobial Resistance ◽

10.1016/j.jgar.2020.02.020 ◽

2020 ◽

Vol 21 ◽

pp. 46-48 ◽

Cited By ~ 1

Author(s):

Tao Jiang ◽

Juan Xu ◽

Fang He

Keyword(s):

Bloodstream Infection ◽

Allelic Variants ◽

Ralstonia Pickettii

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Alteration of salivary microbiome in periodontitis with or without type-2 diabetes mellitus and metformin treatment

Scientific Reports ◽

10.1038/s41598-020-72035-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Xiaoyu Sun ◽

Meihui Li ◽

Li Xia ◽

Zhaohui Fang ◽

Shenjun Yu ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Rrna Gene ◽

Ralstonia Pickettii ◽

Health Group ◽

Significant Difference ◽

Rrna Gene Sequencing ◽

Hypoglycemic Therapy

Abstract We aimed to explore the effects of type-2 diabetes mellitus (T2DM) and hypoglycemic therapy on the salivary microbiome in periodontitis patients and identify the potential salivary micro-biomarker for the early warning of T2DM. Saliva samples were collected from healthy individuals (Health), periodontitis patients (P), T2DM patients, periodontitis patients with T2DM (DAP), and DAP patients treated with Metformin (Met). Samples were determined by16S rRNA gene sequencing. 29 phyla, 322 genera, and 333 species of salivary microbiome were annotated. Compared to the Health group, the P and DAP group showed a significantly higher diversity of saliva microbiota, while the T2DM and Met group had no significant difference in microbial abundance but showed a trend of increasing diversity. Other than well-known periodontitis-inducing pathogens, the proportion of Prevotella copri, Alloprevotella rava, and Ralstonia pickettii, etc. were also significantly increased in periodontitis patients with or without T2DM. After effective glycemic control, the abundance of Prevotella copri, Alloprevotella rava, Ralstonia pickettii, etc. decreased in periodontitis patients with companion T2DM. The accuracies of the classification models in differentiating Health-vs.-P, DAP-vs.-P, and T2DM-vs.-P were 100%, 96.3%, and 98.1%, respectively. Hypoglycemic therapy could reconstruct the saliva microbiota and hence improve the localized conditions of diabetes patients with periodontitis.

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Identification of A Novel Arsenic Resistance Transposon Nested in A Mercury Resistance Transposon of Bacillus sp. MB24

Microorganisms ◽

10.3390/microorganisms7110566 ◽

2019 ◽

Vol 7 (11) ◽

pp. 566 ◽

Cited By ~ 1

Author(s):

Mei-Fang Chien ◽

Ying-Ning Ho ◽

Hui-Erh Yang ◽

Masaru Narita ◽

Keisuke Miyauchi ◽

...

Keyword(s):

Gene Clusters ◽

Whole Genome Sequence ◽

Mercury Resistance ◽

Bacillus Sp ◽

Arsenic Resistance ◽

First Case ◽

Arsenite Resistance ◽

Ars Operon ◽

Minamata Bay ◽

Bacterium Bacillus

A novel TnMERI1-like transposon designated as TnMARS1 was identified from mercury resistant Bacilli isolated from Minamata Bay sediment. Two adjacent ars operon-like gene clusters, ars1 and ars2, flanked by a pair of 78-bp inverted repeat sequences, which resulted in a 13.8-kbp transposon-like fragment, were found to be sandwiched between two transposable genes of the TnMERI1-like transposon of a mercury resistant bacterium, Bacillus sp. MB24. The presence of a single transcription start site in each cluster determined by 5′-RACE suggested that both are operons. Quantitative real time RT-PCR showed that the transcription of the arsR genes contained in each operon was induced by arsenite, while arsR2 responded to arsenite more sensitively and strikingly than arsR1 did. Further, arsenic resistance complementary experiments showed that the ars2 operon conferred arsenate and arsenite resistance to an arsB-knocked out Bacillus host, while the ars1 operon only raised arsenite resistance slightly. This transposon nested in TnMARS1 was designated as TnARS1. Multi-gene cluster blast against bacteria and Bacilli whole genome sequence databases suggested that TnMARS1 is the first case of a TnMERI1-like transposon combined with an arsenic resistance transposon. The findings of this study suggested that TnMERI1-like transposons could recruit other mobile elements into its genetic structure, and subsequently cause horizontal dissemination of both mercury and arsenic resistances among Bacilli in Minamata Bay.

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