1
|
Occhialini A, Lenaghan SC. Plastid engineering using episomal DNA. PLANT CELL REPORTS 2023:10.1007/s00299-023-03020-x. [PMID: 37127835 DOI: 10.1007/s00299-023-03020-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023]
Abstract
KEY MESSAGE Novel episomal systems have the potential to accelerate plastid genetic engineering for application in plant synthetic biology. Plastids represent valuable subcellular compartments for genetic engineering of plants with intrinsic advantages to engineering the nucleus. The ability to perform site-specific transgene integration by homologous recombination (HR), coordination of transgene expression in operons, and high production of heterologous proteins, all make plastids an attractive target for synthetic biology. Typically, plastid engineering is performed by homologous recombination; however, episomal-replicating vectors have the potential to accelerate the design/build/test cycles for plastid engineering. By accelerating the timeline from design to validation, it will be possible to generate translational breakthroughs in fields ranging from agriculture to biopharmaceuticals. Episomal-based plastid engineering will allow precise single step metabolic engineering in plants enabling the installation of complex synthetic circuits with the ambitious goal of reaching similar efficiency and flexibility of to the state-of-the-art genetic engineering of prokaryotic systems. The prospect to design novel episomal systems for production of transplastomic marker-free plants will also improve biosafety for eventual release in agriculture.
Collapse
Affiliation(s)
- Alessandro Occhialini
- Department of Plant Sciences, University of Tennessee, 112 Plant Biotechnology Building 2505 E J Chapman Drive, Knoxville, TN, 37996, USA.
- Center for Agricultural Synthetic Biology (CASB), University of Tennessee, 2640 Morgan Circle Drive, Knoxville, TN, 37996, USA.
| | - Scott C Lenaghan
- Center for Agricultural Synthetic Biology (CASB), University of Tennessee, 2640 Morgan Circle Drive, Knoxville, TN, 37996, USA.
- Department of Food Science, University of Tennessee, 102 Food Safety and Processing Building 2600 River Dr., Knoxville, TN, 37996, USA.
| |
Collapse
|
2
|
Xiao R, Huang D, Du L, Song B, Yin L, Chen Y, Gao L, Li R, Huang H, Zeng G. Antibiotic resistance in soil-plant systems: A review of the source, dissemination, influence factors, and potential exposure risks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161855. [PMID: 36708845 DOI: 10.1016/j.scitotenv.2023.161855] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/14/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
As an emerging environmental contaminant, the widespread of antibiotic resistance has caused a series of environmental issues and human health concerns. A load of antibiotic residues induced by agricultural practices have exerted selective pressure to bacterial communities in the soil-plant system, which facilitated the occurrence and dissemination of antibiotic resistance genes (ARGs) through horizontal gene transfer. As a result, the enrichment of ARGs within crops at harvest under the influence of food ingestion could lead to critical concerns of public health. In this review, the prevalence and dissemination of antibiotic resistance in the soil-plant system are highlighted. Moreover, different underlying mechanisms and detection methods for ARGs transfer between the soil environment and plant compartments are summarized and discussed. On the other hand, a wide range of influencing factors for the transfer and distribution of antibiotic resistance within the soil-plant system are also presented and discussed. In response to exposure of antibiotic residues and resistomes, corresponding hazard identification assessments have been summarized, which could provide beneficial guides of the toxicological tolerance for the general population. Finally, further research priorities for detection and management ARGs spread are also suggested.
Collapse
Affiliation(s)
- Ruihao Xiao
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Danlian Huang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China.
| | - Li Du
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Biao Song
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Lingshi Yin
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Yashi Chen
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Lan Gao
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Ruijin Li
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Hai Huang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China.
| |
Collapse
|
3
|
Riva V, Patania G, Riva F, Vergani L, Crotti E, Mapelli F. Acinetobacter baylyi Strain BD413 Can Acquire an Antibiotic Resistance Gene by Natural Transformation on Lettuce Phylloplane and Enter the Endosphere. Antibiotics (Basel) 2022; 11:antibiotics11091231. [PMID: 36140010 PMCID: PMC9495178 DOI: 10.3390/antibiotics11091231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 12/03/2022] Open
Abstract
Antibiotic resistance spread must be considered in a holistic framework which comprises the agri-food ecosystems, where plants can be considered a bridge connecting water and soil habitats with the human microbiome. However, the study of horizontal gene transfer events within the plant microbiome is still overlooked. Here, the environmental strain Acinetobacter baylyi BD413 was used to study the acquisition of extracellular DNA (exDNA) carrying an antibiotic resistance gene (ARG) on lettuce phylloplane, performing experiments at conditions (i.e., plasmid quantities) mimicking those that can be found in a water reuse scenario. Moreover, we assessed how the presence of a surfactant, a co-formulant widely used in agriculture, affected exDNA entry in bacteria and plant tissues, besides the penetration and survival of bacteria into the leaf endosphere. Natural transformation frequency in planta was comparable to that occurring under optimal conditions (i.e., temperature, nutrient provision, and absence of microbial competitors), representing an entrance pathway of ARGs into an epiphytic bacterium able to penetrate the endosphere of a leafy vegetable. The presence of the surfactant determined a higher presence of culturable transformant cells in the leaf tissues but did not significantly increase exDNA entry in A. baylyi BD413 cells and lettuce leaves. More research on HGT (Horizontal Gene Transfer) mechanisms in planta should be performed to obtain experimental data on produce safety in terms of antibiotic resistance.
Collapse
|
4
|
Philips JG, Martin-Avila E, Robold AV. Horizontal gene transfer from genetically modified plants - Regulatory considerations. Front Bioeng Biotechnol 2022; 10:971402. [PMID: 36118580 PMCID: PMC9471246 DOI: 10.3389/fbioe.2022.971402] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/05/2022] [Indexed: 11/13/2022] Open
Abstract
Gene technology regulators receive applications seeking permission for the environmental release of genetically modified (GM) plants, many of which possess beneficial traits such as improved production, enhanced nutrition and resistance to drought, pests and diseases. The regulators must assess the risks to human and animal health and to the environment from releasing these GM plants. One such consideration, of many, is the likelihood and potential consequence of the introduced or modified DNA being transferred to other organisms, including people. While such gene transfer is most likely to occur to sexually compatible relatives (vertical gene transfer), horizontal gene transfer (HGT), which is the acquisition of genetic material that has not been inherited from a parent, is also a possibility considered during these assessments. Advances in HGT detection, aided by next generation sequencing, have demonstrated that HGT occurrence may have been previously underestimated. In this review, we provide updated evidence on the likelihood, factors and the barriers for the introduced or modified DNA in GM plants to be horizontally transferred into a variety of recipients. We present the legislation and frameworks the Australian Gene Technology Regulator adheres to with respect to the consideration of risks posed by HGT. Such a perspective may generally be applicable to regulators in other jurisdictions as well as to commercial and research organisations who develop GM plants.
Collapse
|
5
|
Mishra V, Mishra R, Shamra RS. Ribosome inactivating proteins - An unfathomed biomolecule for developing multi-stress tolerant transgenic plants. Int J Biol Macromol 2022; 210:107-122. [PMID: 35525494 DOI: 10.1016/j.ijbiomac.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/10/2022] [Accepted: 05/01/2022] [Indexed: 11/15/2022]
Abstract
Transgenic crops would serve as a tool to overcome the forthcoming crisis in food security and environmental safety posed by degrading land and changing global climate. Commercial transgenic crops developed so far focus on single stress; however, sustaining crop yield to ensure food security requires transgenics tolerant to multiple environmental stresses. Here we argue and demonstrate the untapped potential of ribosome inactivating proteins (RIPs), translation inhibitors, as potential transgenes in developing transgenics to combat multiple stresses in the environment. Plant RIPs target the fundamental processes of the cell with very high specificity to the infecting pests. While controlling pathogens, RIPs also cause ectopic expression of pathogenesis-related proteins and trigger systemic acquired resistance. On the other hand, during abiotic stress, RIPs show antioxidant activity and trigger both enzyme-dependent and enzyme-independent metabolic pathways, alleviating abiotic stress such as drought, salinity, temperature, etc. RIPs express in response to specific environmental signals; therefore, their expression obviates additional physiological load on the transgenic plants instead of the constitutive expression. Based on evidence from its biological significance, ecological roles, laboratory- and controlled-environment success of its transgenics, and ethical merits, we unravel the potential of RIPs in developing transgenic plants showing co-tolerance to multiple environmental stresses.
Collapse
Affiliation(s)
- Vandana Mishra
- Bioresources and Environmental Biotechnology Laboratory, Department of Environmental Studies, University of Delhi, Delhi 110007, India.
| | - Ruchi Mishra
- Bioresources and Environmental Biotechnology Laboratory, Department of Environmental Studies, University of Delhi, Delhi 110007, India; Jesus and Mary College, University of Delhi, Chanakyapuri, Delhi 110021, India.
| | - Radhey Shyam Shamra
- Bioresources and Environmental Biotechnology Laboratory, Department of Environmental Studies, University of Delhi, Delhi 110007, India; Delhi School of Climate Change & Sustainability, Institute of Eminence, University of Delhi, Delhi 110007, India.
| |
Collapse
|
6
|
Huang J, Mi J, Yan Q, Wen X, Zhou S, Wang Y, Ma B, Zou Y, Liao X, Wu Y. Animal manures application increases the abundances of antibiotic resistance genes in soil-lettuce system associated with shared bacterial distributions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 787:147667. [PMID: 34004530 DOI: 10.1016/j.scitotenv.2021.147667] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 06/12/2023]
Abstract
An increasing amount of animal manures is being used in agriculture, and the effect of animal manures application on the abundance of antibiotics resistance genes (ARGs) in soil-plant system has attracted widespread attention. However, the impacts of animal manures application on the various types of bacterial distribution that occur in soil-lettuce system are unclear. To address this topic, the effects of poultry manure, swine manure or chemical fertilizer application on ARG abundance and the distribution of shared bacteria were investigated in this study. In a lettuce pot experiment, 13 ARGs and 2 MGEs were quantified by qPCR, and bacterial communities in the soil, lettuce endosphere and lettuce phyllosphere were analysed by 16S rRNA sequence analysis. The results showed that the application of poultry or swine manure significantly increased ARG abundance in the soil, a result attributed mainly to increases in the abundances of tetG and tetC. The application of poultry manure, swine manure and chemical fertilizer significantly increased ARG abundance in the lettuce endosphere, and tetG abundance was significantly increased in the poultry and swine manure groups. However, animal manures application did not significantly increase ARG abundance in the lettuce phyllosphere. Flavobacteriaceae, Sphingomonadaceae and 11 other bacterial families were the shared bacteria in the soil, lettuce endosphere, and phyllosphere. The Streptomycetaceae and Methylobacteriaceae were significantly positively correlated with intI1 in both the soil and endosphere. Chemical fertilizer application increased both the proportions of Sphingomonadaceae and tetX abundance, which were positively correlated in the endosphere. Comamonadaceae and Flavobacteriaceae were not detected in the lettuce endosphere under swine manure application. Cu was related to Flavobacteriaceae in the lettuce endosphere. Overall, poultry and swine manure application significantly increased ARG abundance in the soil-lettuce system, which might be due to the shared bacterial distribution.
Collapse
Affiliation(s)
- Jielan Huang
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China
| | - Jiandui Mi
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Engineering Technology Research Center of Harmless Treatment and Resource Utilization of Livestock Waste, Yunfu, Xinxing 527400, China
| | - Qiufan Yan
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China
| | - Xin Wen
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China
| | - Shizheng Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China
| | - Yan Wang
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Engineering Technology Research Center of Harmless Treatment and Resource Utilization of Livestock Waste, Yunfu, Xinxing 527400, China
| | - Baohua Ma
- Foshan Customs Comprehensive Technology Center, Foshan 528200, China
| | - Yongde Zou
- Foshan Customs Comprehensive Technology Center, Foshan 528200, China
| | - Xindi Liao
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Engineering Technology Research Center of Harmless Treatment and Resource Utilization of Livestock Waste, Yunfu, Xinxing 527400, China
| | - Yinbao Wu
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou 510642, China; National Engineering Research Center for Breeding Swine Industry, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, and Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, Guangdong, China; Ministry of Agriculture Key Laboratory of Tropical Agricultural Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Engineering Technology Research Center of Harmless Treatment and Resource Utilization of Livestock Waste, Yunfu, Xinxing 527400, China.
| |
Collapse
|
7
|
Marker-Free Transplastomic Plants by Excision of Plastid Marker Genes Using Directly Repeated DNA Sequences. Methods Mol Biol 2021. [PMID: 34028764 DOI: 10.1007/978-1-0716-1472-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Excision of marker genes using DNA direct repeats makes use of the efficient native homologous recombination pathway present in the plastids of algae and plants. The method is simple, efficient, and widely applicable to plants and green algae. Marker excision frequency is dependent on the length and number of directly repeated sequences. When two repeats are used a repeat size of greater than 600 bp promotes efficient excision of the marker gene. A wide variety of sequences can be used to make the direct repeats. Only a single round of transformation is required and there is no requirement to introduce site-specific recombinases by retransformation or sexual crosses. Selection is used to maintain the marker and ensure homoplasmy of transgenic plastid genomes (plastomes). Release of selection allows the accumulation of marker-free plastomes generated by marker excision, which is a spontaneous and unidirectional process. Cytoplasmic sorting allows the segregation of cells with marker-free transgenic plastids. The marker-free shoots resulting from direct repeat mediated excision of marker genes have been isolated by vegetative propagation of shoots in the T0 generation. Alternatively, accumulation of marker-free plastomes during growth, development and flowering of T0 plants allows for the collection of seeds that give rise to a high proportion of marker-free T1 seedlings. The procedure enables precise plastome engineering involving insertion of transgenes, point mutations and deletion of genes without the inclusion of any extraneous DNA. The simplicity and convenience of direct repeat excision facilitates its widespread use to isolate marker-free crops.
Collapse
|
8
|
Lasso G, Honig B, Shapira SD. A Sweep of Earth's Virome Reveals Host-Guided Viral Protein Structural Mimicry and Points to Determinants of Human Disease. Cell Syst 2020; 12:82-91.e3. [PMID: 33053371 PMCID: PMC7552982 DOI: 10.1016/j.cels.2020.09.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/03/2020] [Accepted: 09/18/2020] [Indexed: 12/17/2022]
Abstract
Viruses deploy genetically encoded strategies to coopt host machinery and support viral replicative cycles. Here, we use protein structure similarity to scan for molecular mimicry, manifested by structural similarity between viral and endogenous host proteins, across thousands of cataloged viruses and hosts spanning broad ecological niches and taxonomic range, including bacteria, plants and fungi, invertebrates, and vertebrates. This survey identified over 6,000,000 instances of structural mimicry; more than 70% of viral mimics cannot be discerned through protein sequence alone. We demonstrate that the manner and degree to which viruses exploit molecular mimicry varies by genome size and nucleic acid type and identify 158 human proteins that are mimicked by coronaviruses, providing clues about cellular processes driving pathogenesis. Our observations point to molecular mimicry as a pervasive strategy employed by viruses and indicate that the protein structure space used by a given virus is dictated by the host proteome. A record of this paper's transparent peer review process is included in the Supplemental Information.
Collapse
Affiliation(s)
- Gorka Lasso
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA; Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA; Department of Microbiology and Immunology, Albert Einstein College of Medicine, New York, NY, USA
| | - Barry Honig
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA; Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, NY, USA; Zuckerman Mind Brain Behavior Institute, Columbia University Medical Center, New York, NY, USA; Department of Medicine, Columbia University, New York, NY, USA
| | - Sagi D Shapira
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA; Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA.
| |
Collapse
|
9
|
Wünsch D, Strijkstra A, Wöhlbrand L, Freese HM, Scheve S, Hinrichs C, Trautwein K, Maczka M, Petersen J, Schulz S, Overmann J, Rabus R. Global Response of Phaeobacter inhibens DSM 17395 to Deletion of Its 262-kb Chromid Encoding Antibiotic Synthesis. Microb Physiol 2020; 30:9-24. [PMID: 32958725 DOI: 10.1159/000508591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 05/11/2020] [Indexed: 11/19/2022]
Abstract
The marine alphaproteobacterium Phaeobacter inhibens DSM 17395, a member of the Roseobacter group, was recently shown to markedly enhance growth upon deletion of its 262-kb chromid encoding biosynthesis of tropodithietic acid (TDA). To scrutinize the metabolic/regulatory adaptations that underlie enhanced growth of the Δ262 mutant, its transcriptome and proteome compared to the wild type were investigated in process-controlled bioreactors with Casamino Acids as growth substrate. Genome resequencing revealed only few additional genetic changes (a heterogenic insertion, prophage activation, and several point mutations) between wild type and Δ262 mutant, albeit with no conceivable effect on the studied growth physiology. The abundances of the vast majority of transcripts and proteins involved in the catabolic network for complete substrate oxidation to CO2 were found to be unchanged, suggesting that the enhanced amino acid utilization of the Δ262 mutant did not require elevated synthesis of most enzymes of the catabolic network. Similarly, constituents of genetic information processing and cellular processes remained mostly unchanged. In contrast, 426 genes displayed differential expression, of which 410 were localized on the 3.2-Mb chromosome, 5 on the 65-kb chromid, and 11 on the 78-kb chromid. Notably, the branched-chain amino transferase IlvE acting on rapidly utilized Val, Ile, and Leu was upregulated. Moreover, the transportome was reconfigured, as evidenced from increased abundances of transcripts and proteins of several uptake systems for amino acids and inorganic nutrients (e.g., phosphate). Some components of the respiratory chain were also upregulated, which correlates with the higher respiration rates of the Δ262 mutant. Furthermore, chromosomally encoded transcripts and proteins that are peripherally related to TDA biosynthesis (e.g., the serine acyl transferase CysE) were strongly downregulated in the Δ262 mutant. Taken together, these observations reflect adaptations to enhanced growth as well as the functional interconnectivity of the replicons of P. inhibens DSM 17395.
Collapse
Affiliation(s)
- Daniel Wünsch
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Annemieke Strijkstra
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Lars Wöhlbrand
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Heike M Freese
- Department Microbial Ecology and Diversity, Leibniz Institute German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Sabine Scheve
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Christina Hinrichs
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Kathleen Trautwein
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Michael Maczka
- Institute of Organic Chemistry, Technische Universität Carolo-Wilhelmina zu Braunschweig, Braunschweig, Germany
| | - Jörn Petersen
- Department Microbial Ecology and Diversity, Leibniz Institute German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Carolo-Wilhelmina zu Braunschweig, Braunschweig, Germany
| | - Jörg Overmann
- Department Microbial Ecology and Diversity, Leibniz Institute German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Ralf Rabus
- General and Molecular Microbiology, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany,
| |
Collapse
|
10
|
Thompson MG, Moore WM, Hummel NFC, Pearson AN, Barnum CR, Scheller HV, Shih PM. Agrobacterium tumefaciens: A Bacterium Primed for Synthetic Biology. BIODESIGN RESEARCH 2020; 2020:8189219. [PMID: 37849895 PMCID: PMC10530663 DOI: 10.34133/2020/8189219] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 04/26/2020] [Indexed: 10/19/2023] Open
Abstract
Agrobacterium tumefaciens is an important tool in plant biotechnology due to its natural ability to transfer DNA into the genomes of host plants. Genetic manipulations of A. tumefaciens have yielded considerable advances in increasing transformational efficiency in a number of plant species and cultivars. Moreover, there is overwhelming evidence that modulating the expression of various mediators of A. tumefaciens virulence can lead to more successful plant transformation; thus, the application of synthetic biology to enable targeted engineering of the bacterium may enable new opportunities for advancing plant biotechnology. In this review, we highlight engineering targets in both A. tumefaciens and plant hosts that could be exploited more effectively through precision genetic control to generate high-quality transformation events in a wider range of host plants. We then further discuss the current state of A. tumefaciens and plant engineering with regard to plant transformation and describe how future work may incorporate a rigorous synthetic biology approach to tailor strains of A. tumefaciens used in plant transformation.
Collapse
Affiliation(s)
- Mitchell G. Thompson
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Biology, University of California-Davis, Davis, CA, USA
| | - William M. Moore
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA, USA
| | - Niklas F. C. Hummel
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Biology, University of California-Davis, Davis, CA, USA
| | - Allison N. Pearson
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Collin R. Barnum
- Department of Plant Biology, University of California-Davis, Davis, CA, USA
| | - Henrik V. Scheller
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA, USA
| | - Patrick M. Shih
- Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Plant Biology, University of California-Davis, Davis, CA, USA
- Genome Center, University of California-Davis, Davis, CA, USA
| |
Collapse
|
11
|
Tiwari P, Bae H. Horizontal Gene Transfer and Endophytes: An Implication for the Acquisition of Novel Traits. PLANTS (BASEL, SWITZERLAND) 2020; 9:E305. [PMID: 32121565 PMCID: PMC7154830 DOI: 10.3390/plants9030305] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/19/2020] [Accepted: 02/19/2020] [Indexed: 02/06/2023]
Abstract
Horizontal gene transfer (HGT), an important evolutionary mechanism observed in prokaryotes, is the transmission of genetic material across phylogenetically distant species. In recent years, the availability of complete genomes has facilitated the comprehensive analysis of HGT and highlighted its emerging role in the adaptation and evolution of eukaryotes. Endophytes represent an ecologically favored association, which highlights its beneficial attributes to the environment, in agriculture and in healthcare. The HGT phenomenon in endophytes, which features an important biological mechanism for their evolutionary adaptation within the host plant and simultaneously confers "novel traits" to the associated microbes, is not yet completely understood. With a focus on the emerging implications of HGT events in the evolution of biological species, the present review discusses the occurrence of HGT in endophytes and its socio-economic importance in the current perspective. To our knowledge, this review is the first report that provides a comprehensive insight into the impact of HGT in the adaptation and evolution of endophytes.
Collapse
Affiliation(s)
| | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea;
| |
Collapse
|
12
|
Pu C, Yu Y, Diao J, Gong X, Li J, Sun Y. Exploring the persistence and spreading of antibiotic resistance from manure to biocompost, soils and vegetables. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 688:262-269. [PMID: 31229823 DOI: 10.1016/j.scitotenv.2019.06.081] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
The main avenue in which antibiotic resistance enters soils is through the application of livestock manure. However, whether antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) persist and spread to vegetables with the application of manure and manure products is still unclear. This study assessed seven kinds of cultured ARB, 221 ARGs subtypes and three transposon genes in the vegetable production chain (from manure to biocompost, soils and vegetables). Results showed that at least 80% of ARB, ARGs and transposon genes were removed after aerobic composting. However, aerobic composting did not reduce the diversity of ARGs in pig and chicken manure. A total of 19 ARGs subtypes still persisted during aerobic composting. Compared to the temperature-thermophilic stage, the number of bacteria resistant to erythromycin, the relative abundance of ARGs and IS613 increased 1.7-4.9 times at the temperature-decreasing stage. Direct application of biocompost introduced 11 ARGs subtypes to pakchoi, but these ARGs did not present in biocompost-amended soil. A transposon gene tnpA was also detected in the biocompost-amended soil, but surprisingly was found in the control vegetable. This demonstrated that the transposon gene is intrinsic in pakchoi. Bacterial community analysis and network analysis revealed that a specific genus Terrisporobacter carrying tetO, tetW ermB and tnpA persisted in the vegetable production chain, which may generate a potential risk in the following production. Our study illuminates the persistence and spreading of antibiotic resistance in the vegetable production chain which could help manage the ecological risks arising from antibiotic resistance in manure sources.
Collapse
Affiliation(s)
- Chengjun Pu
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Yao Yu
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Jianxiong Diao
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Xiaoyan Gong
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Ji Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China
| | - Ying Sun
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
13
|
Chen QL, An XL, Zheng BX, Ma YB, Su JQ. Long-term organic fertilization increased antibiotic resistome in phyllosphere of maize. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 645:1230-1237. [PMID: 30248848 DOI: 10.1016/j.scitotenv.2018.07.260] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/18/2018] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Phyllosphere contains various microorganisms that may harbor diverse antibiotic resistance genes (ARGs). However, we know little about the composition of antibiotic resistome and the factors influencing the diversity and abundance of ARGs in the phyllosphere. In this study, 16S rRNA gene amplicon sequencing and high-throughput quantitative PCR approaches were employed to investigate the effects of long-term (over 10 years) organic fertilization on the phyllosphere bacterial communities and antibiotic resistome. Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes dominated in the phyllosphere bacterial communities. Long-term application of sewage sludge and chicken manure altered the phyllosphere bacterial community composition, with a remarkable decrease in bacterial alpha-diversity. A total of 124 unique ARGs were detected in the phyllosphere. The application of sewage sludge and chicken manure significantly increased the abundance of ARGs, with a maximum 2638-fold enrichment. Variation partitioning analysis (VPA) together with network analysis indicated that the profile of ARGs is strongly correlated with bacterial community compositions. These results improve the knowledge about the diversity of plant-associated antibiotic resistome and factors influencing the profile of ARGs in the phyllosphere.
Collapse
Affiliation(s)
- Qing-Lin Chen
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xin-Li An
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Bang-Xiao Zheng
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yi-Bing Ma
- Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jian-Qiang Su
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| |
Collapse
|
14
|
Headd B, Bradford SA. Physicochemical Factors That Favor Conjugation of an Antibiotic Resistant Plasmid in Non-growing Bacterial Cultures in the Absence and Presence of Antibiotics. Front Microbiol 2018; 9:2122. [PMID: 30254617 PMCID: PMC6141735 DOI: 10.3389/fmicb.2018.02122] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/20/2018] [Indexed: 11/13/2022] Open
Abstract
Horizontal gene transfer (HGT) of antibiotic resistance genes has received increased scrutiny from the scientific community in recent years owing to the public health threat associated with antibiotic resistant bacteria. Most studies have examined HGT in growing cultures. We examined conjugation in growing and non-growing cultures of E. coli using a conjugative multi antibiotic and metal resistant plasmid to determine physiochemical parameters that favor horizontal gene transfer. The conjugation frequency in growing and non-growing cultures was generally greater under shaken than non-shaken conditions, presumably due to increased frequency of cell collisions. Non-growing cultures in 9.1 mM NaCl had a similar conjugation frequency to that of growing cultures in Luria-Bertaini broth, whereas those in 1 mM or 90.1 mM NaCl were much lower. This salinity effect on conjugation was attributed to differences in cell-cell interactions and conformational changes in cell surface macromolecules. In the presence of antibiotics, the conjugation frequencies of growing cultures did not increase, but in non-growing cultures of 9.1 mM NaCl supplemented with Cefotaxime the conjugation frequency was as much as nine times greater than that of growing cultures. The mechanism responsible for the increased conjugation in non-growing bacteria was attributed to the likely lack of penicillin-binding protein 3 (the target of Cefotaxime), in non-growing cells that enabled Cefotaxime to interact with the plasmid and induce conjugation. Our results suggests that more attention may be owed to HGT in non-growing bacteria as most bacteria in the environment are likely not growing and the proposed mechanism for increased conjugation may not be unique to the bacteria/plasmid system we studied.
Collapse
Affiliation(s)
- Brendan Headd
- U.S. Salinity Lab, United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Riverside, CA, United States
| | | |
Collapse
|
15
|
de Santis B, Stockhofe N, Wal JM, Weesendorp E, Lallès JP, van Dijk J, Kok E, De Giacomo M, Einspanier R, Onori R, Brera C, Bikker P, van der Meulen J, Kleter G. Case studies on genetically modified organisms (GMOs): Potential risk scenarios and associated health indicators. Food Chem Toxicol 2018; 117:36-65. [DOI: 10.1016/j.fct.2017.08.033] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/03/2017] [Accepted: 08/22/2017] [Indexed: 01/07/2023]
|
16
|
Identification of Major Rhizobacterial Taxa Affected by a Glyphosate-Tolerant Soybean Line via Shotgun Metagenomic Approach. Genes (Basel) 2018; 9:genes9040214. [PMID: 29659545 PMCID: PMC5924556 DOI: 10.3390/genes9040214] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/19/2018] [Accepted: 04/13/2018] [Indexed: 01/08/2023] Open
Abstract
The worldwide commercial cultivation of transgenic crops, including glyphosate-tolerant (GT) soybeans, has increased widely during the past 20 years. However, it is accompanied with a growing concern about potential effects of transgenic crops on the soil microbial communities, especially on rhizosphere bacterial communities. Our previous study found that the GT soybean line NZL06-698 (N698) significantly affected rhizosphere bacteria, including some unidentified taxa, through 16S rRNA gene (16S rDNA) V4 region amplicon deep sequencing via Illumina MiSeq. In this study, we performed 16S rDNA V5–V7 region amplicon deep sequencing via Illumina MiSeq and shotgun metagenomic approaches to identify those major taxa. Results of these processes revealed that the species richness and evenness increased in the rhizosphere bacterial communities of N698, the beta diversity of the rhizosphere bacterial communities of N698 was affected, and that certain dominant bacterial phyla and genera were related to N698 compared with its control cultivar Mengdou12. Consistent with our previous findings, this study showed that N698 affects the rhizosphere bacterial communities. In specific, N698 negatively affects Rahnella, Janthinobacterium, Stenotrophomonas, Sphingomonas and Luteibacter while positively affecting Arthrobacter, Bradyrhizobium, Ramlibacter and Nitrospira.
Collapse
|
17
|
Shun-Mei E, Zeng JM, Yuan H, Lu Y, Cai RX, Chen C. Sub-inhibitory concentrations of fluoroquinolones increase conjugation frequency. Microb Pathog 2017; 114:57-62. [PMID: 29174700 DOI: 10.1016/j.micpath.2017.11.036] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 02/08/2023]
Abstract
Bacteria are subjected to sub-minimal inhibitory concentrations (sub-MIC) of antibiotics in various niches where the low-dosage treatment plays a key role in antibiotic resistance selection. However, the mechanism of sub-MIC of antibiotics on the resistant gene transfer is largely unknown. Here, we used Escherichia coli SM10λpir in which the RP4 plasmid was chromosomally-integrated as the donor strain, to investigate the effects of sub-MIC of Ciprofloxacin(Cip) or Levofloxacin(Lev) on conjugational transfer of mobilisable plasmid-pUCP24T from SM10λpir to Pseudomonas aeruginosa. The results showed that the transfer frequency was significantly increased by treating E. coli with sub-MIC of Cip or Lev. To investigate the molecular mechanisms, complete transcriptome sequencing was performed. We found that the sub-MIC of Cip or Lev enhanced the expression of several genes on the RP4 plasmid, which was consistent with the conjugation efficiency. Moreover, the expression of genes associated with SOS response in donor SM10λpir was increased, but had no correlation with conjugation efficiency. These findings suggested that sub-MIC of Cip or Lev may promote conjugational transfer by up-regulating the expression of conjugation associated genes via an SOS-independent mechanism.
Collapse
Affiliation(s)
- E Shun-Mei
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Jian-Ming Zeng
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Hui Yuan
- Department of Gastroenterology, People Hospital, Hubei University of Medicine, Shiyan, China.
| | - Yang Lu
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Ren-Xin Cai
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| | - Cha Chen
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
| |
Collapse
|
18
|
Chen QL, An XL, Zhu YG, Su JQ, Gillings MR, Ye ZL, Cui L. Application of Struvite Alters the Antibiotic Resistome in Soil, Rhizosphere, and Phyllosphere. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017. [PMID: 28628300 DOI: 10.1021/acs.est.7b01420] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Struvite recovered from wastewater is a renewable source of phosphorus and nitrogen and can be used as fertilizer for plant growth. However, antibiotics and resistome can be enriched in the struvite derived from wastewater. Robust understanding of the potential risks after struvite application to soils has remained elusive. Here, we profiled antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in struvite, soil, rhizosphere and phyllosphere of Brassica using high-throughput quantitative PCR. A total of 165 ARGs and 10 MGEs were detected. Application of struvite was found to increase both the abundance and diversity of ARGs in soil, rhizosphere and phyllosphere. In addition, ARGs shared exclusively between Brassica phyllosphere and struvite were identified, indicating that struvite was an important source of ARGs found in phyllosphere. Furthermore, OTUs shared between rhizosphere and phyllosphere were found to significantly correlate with ARGs, suggesting that microbiota in leaf and root could interconnect and ARGs might transfer from struvite to the surface of plants via rhizosphere using bacteria as spreading medium. These findings demonstrated that struvite as an organic fertilizer can facilitate the spread of antibiotic resistance into human food chain and this environment-acquired antibiotic resistance should be put into human health risk assessment system.
Collapse
Affiliation(s)
- Qing-Lin Chen
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
| | - Xin-Li An
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
| | - Yong-Guan Zhu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
| | - Jian-Qiang Su
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
| | - Michael R Gillings
- Department of Biological Sciences, Macquarie University , Sydney, New South Wales 2109, Australia
| | - Zhi-Long Ye
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
| | - Li Cui
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , 1799 Jimei Road, Xiamen 361021, China
| |
Collapse
|
19
|
Genetic Engineering and Sustainable Crop Disease Management: Opportunities for Case-by-Case Decision-Making. SUSTAINABILITY 2016. [DOI: 10.3390/su8050495] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
20
|
Discovery of Novel Plant Interaction Determinants from the Genomes of 163 Root Nodule Bacteria. Sci Rep 2015; 5:16825. [PMID: 26584898 PMCID: PMC4653623 DOI: 10.1038/srep16825] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 10/20/2015] [Indexed: 12/11/2022] Open
Abstract
Root nodule bacteria (RNB) or "rhizobia" are a type of plant growth promoting bacteria, typified by their ability to fix nitrogen for their plant host, fixing nearly 65% of the nitrogen currently utilized in sustainable agricultural production of legume crops and pastures. In this study, we sequenced the genomes of 110 RNB from diverse hosts and biogeographical regions, and undertook a global exploration of all available RNB genera with the aim of identifying novel genetic determinants of symbiotic association and plant growth promotion. Specifically, we performed a subtractive comparative analysis with non-RNB genomes, employed relevant transcriptomic data, and leveraged phylogenetic distribution patterns and sequence signatures based on known precepts of symbiotic- and host-microbe interactions. A total of 184 protein families were delineated, including known factors for nodulation and nitrogen fixation, and candidates with previously unexplored functions, for which a role in host-interaction, -regulation, biocontrol, and more, could be posited. These analyses expand our knowledge of the RNB purview and provide novel targets for strain improvement in the ultimate quest to enhance plant productivity and agricultural sustainability.
Collapse
|
21
|
Esser DS, Leveau JHJ, Meyer KM, Wiegand K. Spatial scales of interactions among bacteria and between bacteria and the leaf surface. FEMS Microbiol Ecol 2015; 91:fiu034. [PMID: 25764562 PMCID: PMC4399446 DOI: 10.1093/femsec/fiu034] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/04/2014] [Accepted: 12/21/2014] [Indexed: 01/11/2023] Open
Abstract
Microbial life on plant leaves is characterized by a multitude of interactions between leaf colonizers and their environment. While the existence of many of these interactions has been confirmed, their spatial scale or reach often remained unknown. In this study, we applied spatial point pattern analysis to 244 distribution patterns of Pantoea agglomerans and Pseudomonas syringae on bean leaves. The results showed that bacterial colonizers of leaves interact with their environment at different spatial scales. Interactions among bacteria were often confined to small spatial scales up to 5-20 μm, compared to interactions between bacteria and leaf surface structures such as trichomes which could be observed in excess of 100 μm. Spatial point-pattern analyses prove a comprehensive tool to determine the different spatial scales of bacterial interactions on plant leaves and will help microbiologists to better understand the interplay between these interactions.
Collapse
Affiliation(s)
- Daniel S Esser
- Department of Ecosystem Modelling, Büsgen-Institute, Georg-August-University of Göttingen, Büsgenweg 4, 37077 Göttingen, Germany
| | - Johan H J Leveau
- Department of Plant Pathology, University of California, Davis, CA 95616-8751, USA
| | - Katrin M Meyer
- Department of Ecosystem Modelling, Büsgen-Institute, Georg-August-University of Göttingen, Büsgenweg 4, 37077 Göttingen, Germany
| | - Kerstin Wiegand
- Department of Ecosystem Modelling, Büsgen-Institute, Georg-August-University of Göttingen, Büsgenweg 4, 37077 Göttingen, Germany
| |
Collapse
|
22
|
Magnetic nanoparticle DNA labeling for individual bacterial cell detection and recovery. J Microbiol Methods 2014; 107:84-91. [DOI: 10.1016/j.mimet.2014.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 09/19/2014] [Indexed: 11/22/2022]
|
23
|
Kumari B, Banerjee SS, Singh V, Das P, Bhowmick AK. Processing of abasic site damaged lesions by APE1 enzyme on DNA adsorbed over normal and organomodified clay. CHEMOSPHERE 2014; 112:503-510. [PMID: 25048946 DOI: 10.1016/j.chemosphere.2014.05.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 05/09/2014] [Accepted: 05/11/2014] [Indexed: 06/03/2023]
Abstract
The efficiency of the apurinic/apyrimidinic endonuclease (APE1) DNA repair enzyme in the processing of abasic site DNA damage lesions at precise location in DNA oligomer duplexes that are adsorbed on clay surfaces was evaluated. Three different forms of clay namely montmorillonite, quaternary ammonium salt modified montmorillonite and its boiled counterpart i.e. partially devoid of organic moiety were used for a comparative study of adsorption, desorption and DNA repair efficiency on their surfaces. The interaction between the DNA and the clay was analysed by X-ray diffraction, Atomic force microscopy, UV-Vis spectroscopy and Infrared spectroscopy. The abasic site cleavage efficiency of APE1 enzyme was quantitatively evaluated by polyacrylamide gel electrophoresis. Apart from the difference in the DNA adsorption or desorption capacity of the various forms of clay, substantial variation in the repair efficiency of abasic sites initiated by the APE1 enzyme on the clay surfaces was observed. The incision efficiency of APE1 enzyme at abasic sites was found to be greatly diminished, when the DNA was adsorbed over organomodified montmorillonite. The reduced repair activity indicates an important role of the pendant surfactant groups on the clay surfaces in directing APE1 mediated cleavage of abasic site DNA damage lesions.
Collapse
Affiliation(s)
- Bhavini Kumari
- Department of Chemistry, Indian Institute of Technology Patna, Patna 800013, Bihar, India
| | - Shib Shankar Banerjee
- Department of Materials Science and Engineering, Indian Institute of Technology Patna, Patna 800013, Bihar, India
| | - Vandana Singh
- Department of Chemistry, Indian Institute of Technology Patna, Patna 800013, Bihar, India
| | - Prolay Das
- Department of Chemistry, Indian Institute of Technology Patna, Patna 800013, Bihar, India.
| | - Anil K Bhowmick
- Department of Materials Science and Engineering, Indian Institute of Technology Patna, Patna 800013, Bihar, India
| |
Collapse
|
24
|
Nielsen KM, Bøhn T, Townsend JP. Detecting rare gene transfer events in bacterial populations. Front Microbiol 2014; 4:415. [PMID: 24432015 PMCID: PMC3882822 DOI: 10.3389/fmicb.2013.00415] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 12/16/2013] [Indexed: 11/23/2022] Open
Abstract
Horizontal gene transfer (HGT) enables bacteria to access, share, and recombine genetic variation, resulting in genetic diversity that cannot be obtained through mutational processes alone. In most cases, the observation of evolutionary successful HGT events relies on the outcome of initially rare events that lead to novel functions in the new host, and that exhibit a positive effect on host fitness. Conversely, the large majority of HGT events occurring in bacterial populations will go undetected due to lack of replication success of transformants. Moreover, other HGT events that would be highly beneficial to new hosts can fail to ensue due to lack of physical proximity to the donor organism, lack of a suitable gene transfer mechanism, genetic compatibility, and stochasticity in tempo-spatial occurrence. Experimental attempts to detect HGT events in bacterial populations have typically focused on the transformed cells or their immediate offspring. However, rare HGT events occurring in large and structured populations are unlikely to reach relative population sizes that will allow their immediate identification; the exception being the unusually strong positive selection conferred by antibiotics. Most HGT events are not expected to alter the likelihood of host survival to such an extreme extent, and will confer only minor changes in host fitness. Due to the large population sizes of bacteria and the time scales involved, the process and outcome of HGT are often not amenable to experimental investigation. Population genetic modeling of the growth dynamics of bacteria with differing HGT rates and resulting fitness changes is therefore necessary to guide sampling design and predict realistic time frames for detection of HGT, as it occurs in laboratory or natural settings. Here we review the key population genetic parameters, consider their complexity and highlight knowledge gaps for further research.
Collapse
Affiliation(s)
- Kaare M Nielsen
- Department of Pharmacy, Faculty of Health Sciences, University of Tromsø Tromsø, Norway ; GenØk-Centre for Biosafety, The Science Park Tromsø, Norway
| | - Thomas Bøhn
- Department of Pharmacy, Faculty of Health Sciences, University of Tromsø Tromsø, Norway ; GenØk-Centre for Biosafety, The Science Park Tromsø, Norway
| | - Jeffrey P Townsend
- Department of Biostatistics, Yale University New Haven, CT, USA ; Program in Computational Biology and Bioinformatics, Yale University New Haven, CT, USA ; Program in Microbiology, Yale University New Haven, CT, USA
| |
Collapse
|
25
|
Mudd EA, Madesis P, Avila EM, Day A. Excision of plastid marker genes using directly repeated DNA sequences. Methods Mol Biol 2014; 1132:107-23. [PMID: 24599849 DOI: 10.1007/978-1-62703-995-6_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Excision of marker genes using DNA direct repeats makes use of the predominant homologous recombination pathways present in the plastids of algae and plants. The method is simple, efficient, and widely applicable to plants and microalgae. Marker excision frequency is dependent on the length and number of directly repeated sequences. When two repeats are used a repeat size of greater than 600 bp promotes efficient excision of the marker gene. A wide variety of sequences can be used to make the direct repeats. Only a single round of transformation is required, and there is no requirement to introduce site-specific recombinases by retransformation or sexual crosses. Selection is used to maintain the marker and ensure homoplasmy of transgenic plastid genomes. Release of selection allows the accumulation of marker-free plastid genomes generated by marker excision, which is spontaneous, random, and a unidirectional process. Positive selection is provided by linking marker excision to restoration of the coding region of an herbicide resistance gene from two overlapping but incomplete coding regions. Cytoplasmic sorting allows the segregation of cells with marker-free transgenic plastids. The marker-free shoots resulting from direct repeat-mediated excision of marker genes have been isolated by vegetative propagation of shoots in the T0 generation. Alternatively, accumulation of marker-free plastid genomes during growth, development and flowering of T0 plants allows the collection of seeds that give rise to a high proportion of marker-free T1 seedlings. The simplicity and convenience of direct repeat excision facilitates its widespread use to isolate marker-free crops.
Collapse
Affiliation(s)
- Elisabeth A Mudd
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | | | | | | |
Collapse
|
26
|
|
27
|
Gao C, Ren X, Mason AS, Liu H, Xiao M, Li J, Fu D. Horizontal gene transfer in plants. Funct Integr Genomics 2013; 14:23-9. [PMID: 24132513 DOI: 10.1007/s10142-013-0345-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 10/03/2013] [Accepted: 10/07/2013] [Indexed: 01/12/2023]
Abstract
Horizontal gene transfer (HGT) describes the transmission of genetic material across species boundaries. HGT often occurs in microbic and eukaryotic genomes. However, the pathways by which HGTs occur in multicellular eukaryotes, especially in plants, are not well understood. We systematically summarized more than ten possible pathways for HGT. The intimate contact which frequently occurs in parasitism, symbiosis, pathogen, epiphyte, entophyte, and grafting interactions could promote HGTs between two species. Besides these direct transfer methods, genes can be exchanged with a vector as a bridge: possible vectors include pollen, fungi, bacteria, viruses, viroids, plasmids, transposons, and insects. HGT, especially when involving horizontal transfer of transposable elements, is recognized as a significant force propelling genomic variation and biological innovation, playing an important functional and evolutionary role in both eukaryotic and prokaryotic genomes. We proposed possible mechanisms by which HGTs can occur, which is useful in understanding the genetic information exchange among distant species or distant cellular components.
Collapse
Affiliation(s)
- Caihua Gao
- Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Chongqing, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
28
|
Affiliation(s)
- Peter Gahan
- Anatomy & Human Sciences; King's College London; London Bridge London SE1 1UL UK
| |
Collapse
|
29
|
Ashbolt NJ, Amézquita A, Backhaus T, Borriello P, Brandt KK, Collignon P, Coors A, Finley R, Gaze WH, Heberer T, Lawrence JR, Larsson DGJ, McEwen SA, Ryan JJ, Schönfeld J, Silley P, Snape JR, Van den Eede C, Topp E. Human Health Risk Assessment (HHRA) for environmental development and transfer of antibiotic resistance. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:993-1001. [PMID: 23838256 PMCID: PMC3764079 DOI: 10.1289/ehp.1206316] [Citation(s) in RCA: 385] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 07/03/2013] [Indexed: 05/04/2023]
Abstract
BACKGROUND Only recently has the environment been clearly implicated in the risk of antibiotic resistance to clinical outcome, but to date there have been few documented approaches to formally assess these risks. OBJECTIVE We examined possible approaches and sought to identify research needs to enable human health risk assessments (HHRA) that focus on the role of the environment in the failure of antibiotic treatment caused by antibiotic-resistant pathogens. METHODS The authors participated in a workshop held 4-8 March 2012 in Québec, Canada, to define the scope and objectives of an environmental assessment of antibiotic-resistance risks to human health. We focused on key elements of environmental-resistance-development "hot spots," exposure assessment (unrelated to food), and dose response to characterize risks that may improve antibiotic-resistance management options. DISCUSSION Various novel aspects to traditional risk assessments were identified to enable an assessment of environmental antibiotic resistance. These include a) accounting for an added selective pressure on the environmental resistome that, over time, allows for development of antibiotic-resistant bacteria (ARB); b) identifying and describing rates of horizontal gene transfer (HGT) in the relevant environmental "hot spot" compartments; and c) modifying traditional dose-response approaches to address doses of ARB for various health outcomes and pathways. CONCLUSIONS We propose that environmental aspects of antibiotic-resistance development be included in the processes of any HHRA addressing ARB. Because of limited available data, a multicriteria decision analysis approach would be a useful way to undertake an HHRA of environmental antibiotic resistance that informs risk managers.
Collapse
Affiliation(s)
- Nicholas J Ashbolt
- US Environmental Protection Agency, Office of Research and Development, Cincinnati, Ohio 45268, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Rizzo L, Manaia C, Merlin C, Schwartz T, Dagot C, Ploy MC, Michael I, Fatta-Kassinos D. Urban wastewater treatment plants as hotspots for antibiotic resistant bacteria and genes spread into the environment: a review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 447:345-60. [PMID: 23396083 DOI: 10.1016/j.scitotenv.2013.01.032] [Citation(s) in RCA: 1198] [Impact Index Per Article: 108.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/08/2013] [Accepted: 01/08/2013] [Indexed: 05/20/2023]
Abstract
Urban wastewater treatment plants (UWTPs) are among the main sources of antibiotics' release into the environment. The occurrence of antibiotics may promote the selection of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB), which shade health risks to humans and animals. In this paper the fate of ARB and ARGs in UWTPs, focusing on different processes/technologies (i.e., biological processes, advanced treatment technologies and disinfection), was critically reviewed. The mechanisms by which biological processes influence the development/selection of ARB and ARGs transfer are still poorly understood. Advanced treatment technologies and disinfection process are regarded as a major tool to control the spread of ARB into the environment. In spite of intense efforts made over the last years to bring solutions to control antibiotic resistance spread in the environment, there are still important gaps to fill in. In particular, it is important to: (i) improve risk assessment studies in order to allow accurate estimates about the maximal abundance of ARB in UWTPs effluents that would not pose risks for human and environmental health; (ii) understand the factors and mechanisms that drive antibiotic resistance maintenance and selection in wastewater habitats. The final objective is to implement wastewater treatment technologies capable of assuring the production of UWTPs effluents with an acceptable level of ARB.
Collapse
Affiliation(s)
- L Rizzo
- Department of Civil Engineering, University of Salerno, 84084, Fisciano (SA), Italy.
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Matsuda A, Kurono N, Kawano C, Shirota K, Hirabayashi A, Horino M, Etchuya R, Sobue R, Sasaki Y, Miyaue S, Sekoguchi A, Sugiura C, Shibata Y, Ito M, Ando T, Maeda S. Genome-wide screen for Escherichia coli genes involved in repressing cell-to-cell transfer of non-conjugative plasmids. Biochem Biophys Res Commun 2012; 428:445-50. [PMID: 23131563 DOI: 10.1016/j.bbrc.2012.10.098] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2012] [Accepted: 10/24/2012] [Indexed: 10/27/2022]
Abstract
Acquiring new genetic traits by lateral gene transfer is a bacterial strategy for environment adaptation. We previously showed that Escherichia coli could laterally transmit non-conjugative plasmids in co-cultures containing strains with and without the plasmid. In this study, using the Keio collection, a comprehensive library of E. coli knock-out mutants for non-essential genes, we screened for genes responsible for repressing cell-to-cell plasmid transfer in recipient cells. By stepwise screening, we identified 55 'transfer-up' mutants that exhibited approximately 2- to 30-fold increased activities. We confirmed plasmid acquisition by these 'up' mutants and revealed that there were no significant changes in antibiotic resistance in the original Keio strains. The presumed functions of these gene products covered a wide range of activities, including metabolism and synthesis, transport, transcription or translation and others. Two competence-gene homologues (ybaV and yhiR) were identified from among these genes. The presumed localizations of these 55 gene products were estimated to be 34 cytoplasmic proteins, 20 in or around the cell surface and 1 unknown location. Our results suggest that these 55 genes may be involved in repressing plasmid uptake during cell-to-cell plasmid transfer.
Collapse
Affiliation(s)
- Ayako Matsuda
- Graduate School of Humanities and Sciences, Nara Women's University, Kitauoya-nishimachi, Nara 630-8506, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Seitz P, Blokesch M. Cues and regulatory pathways involved in natural competence and transformation in pathogenic and environmental Gram-negative bacteria. FEMS Microbiol Rev 2012; 37:336-63. [PMID: 22928673 DOI: 10.1111/j.1574-6976.2012.00353.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 07/27/2012] [Accepted: 08/21/2012] [Indexed: 12/23/2022] Open
Abstract
Bacterial genomics is flourishing, as whole-genome sequencing has become affordable, readily available and rapid. As a result, it has become clear how frequently horizontal gene transfer (HGT) occurs in bacteria. The potential implications are highly significant because HGT contributes to several processes, including the spread of antibiotic-resistance cassettes, the distribution of toxin-encoding phages and the transfer of pathogenicity islands. Three modes of HGT are recognized in bacteria: conjugation, transduction and natural transformation. In contrast to the first two mechanisms, natural competence for transformation does not rely on mobile genetic elements but is driven solely by a developmental programme in the acceptor bacterium. Once the bacterium becomes competent, it is able to take up DNA from the environment and to incorporate the newly acquired DNA into its own chromosome. The initiation and duration of competence differ significantly among bacteria. In this review, we outline the latest data on representative naturally transformable Gram-negative bacteria and how their competence windows differ. We also summarize how environmental cues contribute to the initiation of competence in a subset of naturally transformable Gram-negative bacteria and how the complexity of the niche might dictate the fine-tuning of the competence window.
Collapse
Affiliation(s)
- Patrick Seitz
- Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | | |
Collapse
|
33
|
Kurono N, Matsuda A, Etchuya R, Sobue R, Sasaki Y, Ito M, Ando T, Maeda S. Genome-wide screening of Escherichia coli genes involved in execution and promotion of cell-to-cell transfer of non-conjugative plasmids: rodZ (yfgA) is essential for plasmid acceptance in recipient cells. Biochem Biophys Res Commun 2012; 421:119-23. [PMID: 22497891 DOI: 10.1016/j.bbrc.2012.03.127] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 03/27/2012] [Indexed: 01/11/2023]
Abstract
Acquisition of new genetic traits by horizontal gene transfer is a bacterial strategy for adaptation to the environment. We previously showed that Escherichia coli can transmit non-conjugative plasmids laterally in a co-culture containing strains with and without the plasmid. In this study, using the Keio collection, a comprehensive library of E. coli knock-out mutants for non-essential genes, we screened for genes responsible for the execution and promotion of cell-to-cell plasmid transfer in recipient cells. By stepwise screening of 'transfer-down' mutants, two essential genes and six promoting genes were obtained. One of the essential genes was priA, which is involved in DNA replication. This priA mutant was also unable to be transformed by artificial transformation methods, probably due to the deficiency of the plasmid maintenance function. The other essential gene was rodZ (yfgA), a gene involved in the regulation of rod-shaped structure of E. coli cells. This rodZ mutant was transformable by all three methods of artificial transformation tested, suggesting that this gene is essential for cell-to-cell plasmid transfer but not for artificial transformation. These are the first data that suggest that rodZ plays an essential role in DNA acquisition.
Collapse
Affiliation(s)
- Naomi Kurono
- Graduate School of Humanities and Sciences, Nara Women's University, Kitauoya-nishimachi, Nara 630-8506, Japan
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Fate of invading bacteria in soil and survival of transformants after simulated uptake of transgenes, as evaluated by a model system based on lindane degradation. Res Microbiol 2012; 163:200-10. [DOI: 10.1016/j.resmic.2012.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 01/19/2012] [Indexed: 11/19/2022]
|
35
|
Townsend JP, Bøhn T, Nielsen KM. Assessing the probability of detection of horizontal gene transfer events in bacterial populations. Front Microbiol 2012; 3:27. [PMID: 22363321 PMCID: PMC3282476 DOI: 10.3389/fmicb.2012.00027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Accepted: 01/16/2012] [Indexed: 11/23/2022] Open
Abstract
Experimental approaches to identify horizontal gene transfer (HGT) events of non-mobile DNA in bacteria have typically relied on detection of the initial transformants or their immediate offspring. However, rare HGT events occurring in large and structured populations are unlikely to be detected in a short time frame. Population genetic modeling of the growth dynamics of bacterial genotypes is therefore necessary to account for natural selection and genetic drift during the time lag and to predict realistic time frames for detection with a given sampling design. Here we draw on statistical approaches to population genetic theory to construct a cohesive probabilistic framework for investigation of HGT of exogenous DNA into bacteria. In particular, the stochastic timing of rare HGT events is accounted for. Integrating over all possible event timings, we provide an equation for the probability of detection, given that HGT actually occurred. Furthermore, we identify the key variables determining the probability of detecting HGT events in four different case scenarios that are representative of bacterial populations in various environments. Our theoretical analysis provides insight into the temporal aspects of dissemination of genetic material, such as antibiotic resistance genes or transgenes present in genetically modified organisms. Due to the long time scales involved and the exponential growth of bacteria with differing fitness, quantitative analyses incorporating bacterial generation time, and levels of selection, such as the one presented here, will be a necessary component of any future experimental design and analysis of HGT as it occurs in natural settings.
Collapse
Affiliation(s)
- Jeffrey P Townsend
- Department of Ecology and Evolutionary Biology, Yale University New Haven, CT, USA
| | | | | |
Collapse
|
36
|
Rizzi A, Raddadi N, Sorlini C, Nordgrd L, Nielsen KM, Daffonchio D. The Stability and Degradation of Dietary DNA in the Gastrointestinal Tract of Mammals: Implications for Horizontal Gene Transfer and the Biosafety of GMOs. Crit Rev Food Sci Nutr 2012; 52:142-61. [DOI: 10.1080/10408398.2010.499480] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
37
|
Elliott KT, Neidle EL. Acinetobacter baylyi ADP1: Transforming the choice of model organism. IUBMB Life 2011; 63:1075-80. [DOI: 10.1002/iub.530] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 06/09/2011] [Indexed: 11/12/2022]
|
38
|
Demanèche S, Monier JM, Dugat-Bony E, Simonet P. Exploration of horizontal gene transfer between transplastomic tobacco and plant-associated bacteria. FEMS Microbiol Ecol 2011; 78:129-36. [PMID: 21564143 DOI: 10.1111/j.1574-6941.2011.01126.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The likelihood of gene transfer from transgenic plants to bacteria is dependent on the transgene copy number and on the presence of homologous sequences for recombination. The large number of chloroplast genomes in a plant cell as well as the prokaryotic origin of the transgene may thus significantly increase the likelihood of gene transfer from transplastomic plants to bacteria. In order to assess the probability of such a transfer, bacterial isolates, screened for their ability to colonize decaying tobacco plant tissue and possessing DNA sequence similarity to the chloroplastic genes accD and rbcL flanking the transgene (aadA), were tested for their ability to take up extracellular DNA (broad host-range pBBR1MCS-3-derived plasmid, transplastomic plant DNA and PCR products containing the genes accD-aadA-rbcL) by natural or electrotransformation. The results showed that among the 16 bacterial isolates tested, six were able to accept foreign DNA and acquire the spectinomycin resistance conferred by the aadA gene on plasmid, but none of them managed to integrate transgenic DNA in their chromosome. Our results provide no indication that the theoretical gene transfer-enhancing properties of transplastomic plants cause horizontal gene transfer at rates above those found in other studies with nuclear transgenes.
Collapse
Affiliation(s)
- Sandrine Demanèche
- Environmental Microbial Genomics Group, Laboratoire AMPERE, UMR CNRS 5005, Ecole Centrale de Lyon, Université de Lyon, Ecully, France.
| | | | | | | |
Collapse
|
39
|
Aminov RI. Horizontal gene exchange in environmental microbiota. Front Microbiol 2011; 2:158. [PMID: 21845185 PMCID: PMC3145257 DOI: 10.3389/fmicb.2011.00158] [Citation(s) in RCA: 351] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 07/11/2011] [Indexed: 01/21/2023] Open
Abstract
Horizontal gene transfer (HGT) plays an important role in the evolution of life on the Earth. This view is supported by numerous occasions of HGT that are recorded in the genomes of all three domains of living organisms. HGT-mediated rapid evolution is especially noticeable among the Bacteria, which demonstrate formidable adaptability in the face of recent environmental changes imposed by human activities, such as the use of antibiotics, industrial contamination, and intensive agriculture. At the heart of the HGT-driven bacterial evolution and adaptation are highly sophisticated natural genetic engineering tools in the form of a variety of mobile genetic elements (MGEs). The main aim of this review is to give a brief account of the occurrence and diversity of MGEs in natural ecosystems and of the environmental factors that may affect MGE-mediated HGT.
Collapse
Affiliation(s)
- Rustam I Aminov
- Rowett Institute of Nutrition and Health, University of Aberdeen Aberdeen, UK
| |
Collapse
|
40
|
Michoux F, Ahmad N, McCarthy J, Nixon PJ. Contained and high-level production of recombinant protein in plant chloroplasts using a temporary immersion bioreactor. PLANT BIOTECHNOLOGY JOURNAL 2011; 9:575-84. [PMID: 21105992 DOI: 10.1111/j.1467-7652.2010.00575.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Chloroplast transformation is a promising approach for the commercial production of recombinant proteins in plants. However, gene containment still remains an issue for the large-scale cultivation of transplastomic plants in the field. Here, we have evaluated the potential of using tobacco transplastomic cell suspensions for the fully contained production of a modified form of the green fluorescent protein (GFP+) and, a vaccine antigen, fragment C of tetanus toxin (TetC). Expression of these proteins in cell suspension cultures (and calli) was much less than in leaves, reaching 0.5%-1.5% of total soluble protein (TSP), but still produced 2.4-7.2 mg/L of liquid culture. Much better expression levels were achieved with a novel protein production platform in which transgenic cell suspension cultures were placed in a temporary immersion bioreactor in the presence of Thidiazuron to initiate shoot formation. GFP+ yield reached 660 mg/L of bioreactor (33% TSP), and TetC accumulated to about 95 mg/L (8% TSP). This new production platform, combining the rapid generation of transplastomic cell suspension cultures and the use of temporary immersion bioreactors, is a promising route for the fully contained low-cost production of recombinant proteins in chloroplasts.
Collapse
Affiliation(s)
- Franck Michoux
- Division of Biology, Faculty of Natural Sciences, Imperial College London, London, UK.
| | | | | | | |
Collapse
|
41
|
Day A, Goldschmidt-Clermont M. The chloroplast transformation toolbox: selectable markers and marker removal. PLANT BIOTECHNOLOGY JOURNAL 2011; 9:540-53. [PMID: 21426476 DOI: 10.1111/j.1467-7652.2011.00604.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Plastid transformation is widely used in basic research and for biotechnological applications. Initially developed in Chlamydomonas and tobacco, it is now feasible in a broad range of species. Selection of transgenic lines where all copies of the polyploid plastid genome are transformed requires efficient markers. A number of traits have been used for selection such as photoautotrophy, resistance to antibiotics and tolerance to herbicides or to other metabolic inhibitors. Restoration of photosynthesis is an effective primary selection method in Chlamydomonas but can only serve as a screening tool in flowering plants. The most successful and widely used markers are derived from bacterial genes that inactivate antibiotics, such as aadA that confers resistance to spectinomycin and streptomycin. For many applications, the presence of a selectable marker that confers antibiotic resistance is not desirable. Efficient marker removal methods are a major attraction of the plastid engineering tool kit. They exploit the homologous recombination and segregation pathways acting on chloroplast genomes and are based on direct repeats, transient co-integration or co-transformation and segregation of trait and marker genes. Foreign site-specific recombinases and their target sites provide an alternative and effective method for removing marker genes from plastids.
Collapse
Affiliation(s)
- Anil Day
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | | |
Collapse
|
42
|
Etchuuya R, Ito M, Kitano S, Shigi F, Sobue R, Maeda S. Cell-to-cell transformation in Escherichia coli: a novel type of natural transformation involving cell-derived DNA and a putative promoting pheromone. PLoS One 2011; 6:e16355. [PMID: 21283723 PMCID: PMC3024429 DOI: 10.1371/journal.pone.0016355] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 12/27/2010] [Indexed: 12/16/2022] Open
Abstract
Escherichia coli is not assumed to be naturally transformable. However, several recent reports have shown that E. coli can express modest genetic competence in certain conditions that may arise in its environment. We have shown previously that spontaneous lateral transfer of non-conjugative plasmids occurs in a colony biofilm of mixed E. coli strains (a set of a donor strain harbouring a plasmid and a plasmid-free recipient strain). In this study, with high-frequency combinations of strains and a plasmid, we constructed the same lateral plasmid transfer system in liquid culture. Using this system, we demonstrated that this lateral plasmid transfer was DNase-sensitive, indicating that it is a kind of transformation in which DNase-accessible extracellular naked DNA is essential. However, this transformation did not occur with purified plasmid DNA and required a direct supply of plasmid from co-existing donor cells. Based on this feature, we have termed this transformation type as 'cell-to-cell transformation'. Analyses using medium conditioned with the high-frequency strain revealed that this strain released a certain factor(s) that promoted cell-to-cell transformation and arrested growth of the other strains. This factor is heat-labile and protease-sensitive, and its roughly estimated molecular mass was between ∼9 kDa and ∼30 kDa, indicating that it is a polypeptide factor. Interestingly, this factor was effective even when the conditioned medium was diluted 10(-5)-10(-6), suggesting that it acts like a pheromone with high bioactivity. Based on these results, we propose that cell-to-cell transformation is a novel natural transformation mechanism in E. coli that requires cell-derived DNA and is promoted by a peptide pheromone. This is the first evidence that suggests the existence of a peptide pheromone-regulated transformation mechanism in E. coli and in Gram-negative bacteria.
Collapse
Affiliation(s)
- Rika Etchuuya
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
| | - Miki Ito
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
| | - Seiko Kitano
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
| | - Fukiko Shigi
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
| | - Rina Sobue
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
| | - Sumio Maeda
- Faculty of Human Life and Environment, Nara Women's University, Nara, Japan
- * E-mail:
| |
Collapse
|
43
|
Xu J, Zhao J, Wang J, Zhao Y, Zhang L, Chu M, Li N. Molecular-based environmental risk assessment of three varieties of genetically engineered cows. Transgenic Res 2011; 20:1043-54. [DOI: 10.1007/s11248-010-9477-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 12/15/2010] [Indexed: 12/11/2022]
|
44
|
|
45
|
Phenotypic and physiological changes in Acinetobacter sp. strain DR1 with exogenous plasmid. Curr Microbiol 2010; 62:249-54. [PMID: 20607540 DOI: 10.1007/s00284-010-9698-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Accepted: 06/10/2010] [Indexed: 10/19/2022]
Abstract
The genus Acinetobacter has been recognized to take up exogenous DNA from the environment. In this study, we conducted natural transformation with a novel diesel-degrading Acinetobacter sp. strain, designated strain DR1, using the broad host range plasmid pRK415. Many factors, including temperature, quantities of DNA, and aeration have proven critically important for efficient natural transformation. Interestingly, the Acinetobacter sp. strain DR1 (pRK415) differed both phenotypically and physiologically from the wild-type strain in several regards, including motility, biofilm formation ability, and responses to oxidative stress: the transformed cells were rendered more sensitive to hydrogen peroxide and cumene hydroperoxide, and their motilities and biofilm formation activity were also attenuated. Our data demonstrated that caution should be exercised when conducting genetic manipulation with plasmids, due to the possibility that phenotypic and physiological changes in the host might occur along with the uptake of plasmids.
Collapse
|
46
|
Kang BG, Ye X, Osburn LD, Stewart CN, Cheng ZM. Transgenic hybrid aspen overexpressing the Atwbc19 gene encoding an ATP-binding cassette transporter confers resistance to four aminoglycoside antibiotics. PLANT CELL REPORTS 2010; 29:643-650. [PMID: 20383769 DOI: 10.1007/s00299-010-0850-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 02/16/2010] [Accepted: 03/23/2010] [Indexed: 05/29/2023]
Abstract
Antibiotic-resistance genes of bacterial origin are invaluable markers for plant genetic engineering. However, these genes are feared to pose possible risk to human health by horizontal gene transfer from transgenic plants to bacteria, potentially resulting in antibiotic-resistant pathogenic bacteria; this is a considerable regulatory concern in some countries. The Atwbc19 gene, encoding an Arabidopsis thaliana ATP-binding cassette transporter, has been reported to confer resistance to kanamycin specifically as an alternative to bacterial antibiotic-resistance genes. In this report, we transformed hybrid aspen (Populus canescens x P. grandidentata) with the Atwbc19 gene. Unlike Atwbc19-transgenic tobacco that was only resistant to kanamycin, the transgenic Populus plants also showed resistance to three other aminoglycoside antibiotics (neomycin, geneticin, and paromomycin) at comparable levels to plants containing a CaMV35S-nptII cassette. Although it is unknown why the transgenic Populus with the Atwbc19 gene is resistant to all aminoglycoside antibiotics tested, the broad utility of the Atwbc19 gene as a reporter gene is confirmed here in a second dicot species. Because the Atwbc19 gene is plant-ubiquitous, it might serve as an alternative selectable marker to current bacterial antibiotic-resistance marker genes and alleviate the potential risk for horizontal transfer of bacterial-resistance genes in transgenic plants.
Collapse
Affiliation(s)
- Byung-Guk Kang
- Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, USA
| | | | | | | | | |
Collapse
|
47
|
Lyon DY, Monier JM, Dupraz S, Freissinet C, Simonet P, Vogel TM. Integrity and biological activity of DNA after UV exposure. ASTROBIOLOGY 2010; 10:285-292. [PMID: 20446869 DOI: 10.1089/ast.2009.0359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The field of astrobiology lacks a universal marker with which to indicate the presence of life. This study supports the proposal to use nucleic acids, specifically DNA, as a signature of life (biosignature). In addition to its specificity to living organisms, DNA is a functional molecule that can confer new activities and characteristics to other organisms, following the molecular biology dogma, that is, DNA is transcribed to RNA, which is translated into proteins. Previous criticisms of the use of DNA as a biosignature have asserted that DNA molecules would be destroyed by UV radiation in space. To address this concern, DNA in plasmid form was deposited onto different surfaces and exposed to UVC radiation. The surviving DNA was quantified via the quantitative polymerase chain reaction (qPCR). Results demonstrate increased survivability of DNA attached to surfaces versus non-adsorbed DNA. The DNA was also tested for biological activity via transformation into the bacterium Acinetobacter sp. and assaying for antibiotic resistance conferred by genes encoded by the plasmid. The success of these methods to detect DNA and its gene products after UV exposure (254 nm, 3.5 J/m(2)s) not only supports the use of the DNA molecule as a biosignature on mineral surfaces but also demonstrates that the DNA retained biological activity.
Collapse
Affiliation(s)
- Delina Y Lyon
- Environmental Microbial Genomics Group, Laboratoire Ampère, Ecole Centrale de Lyon, Université de Lyon, Ecully, France
| | | | | | | | | | | |
Collapse
|
48
|
Brigulla M, Wackernagel W. Molecular aspects of gene transfer and foreign DNA acquisition in prokaryotes with regard to safety issues. Appl Microbiol Biotechnol 2010; 86:1027-41. [DOI: 10.1007/s00253-010-2489-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 12/18/2009] [Accepted: 01/31/2010] [Indexed: 11/30/2022]
|
49
|
Fondi M, Bacci G, Brilli M, Papaleo MC, Mengoni A, Vaneechoutte M, Dijkshoorn L, Fani R. Exploring the evolutionary dynamics of plasmids: the Acinetobacter pan-plasmidome. BMC Evol Biol 2010; 10:59. [PMID: 20181243 PMCID: PMC2848654 DOI: 10.1186/1471-2148-10-59] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 02/24/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prokaryotic plasmids have a dual importance in the microbial world: first they have a great impact on the metabolic functions of the host cell, providing additional traits that can be accumulated in the cell without altering the gene content of the bacterial chromosome. Additionally and/or alternatively, from a genome perspective, plasmids can provide a basis for genomic rearrangements via homologous recombination and so they can facilitate the loss or acquisition of genes during these events, which eventually may lead to horizontal gene transfer (HGT). Given their importance for conferring adaptive traits to the host organisms, the interest in plasmid sequencing is growing and now many complete plasmid sequences are available online. RESULTS By using the newly developed Blast2Network bioinformatic tool, a comparative analysis was performed on the plasmid and chromosome sequence data available for bacteria belonging to the genus Acinetobacter, an ubiquitous and clinically important group of gamma-proteobacteria. Data obtained showed that, although most of the plasmids lack mobilization and transfer functions, they have probably a long history of rearrangements with other plasmids and with chromosomes. Indeed, traces of transfers between different species can be disclosed. CONCLUSIONS We show that, by combining plasmid and chromosome similarity, identity based, network analysis, an evolutionary scenario can be described even for highly mobile genetic elements that lack extensively shared genes. In particular we found that transposases and selective pressure for mercury resistance seem to have played a pivotal role in plasmid evolution in Acinetobacter genomes sequenced so far.
Collapse
Affiliation(s)
- Marco Fondi
- Laboratory of Microbial and Molecular Evolution, Dept, of Evolutionary Biology, Via Romana 17-19, University of Florence, I-50125 Florence, Italy
| | | | | | | | | | | | | | | |
Collapse
|