scholarly journals The evolution of insect metallothioneins

2020 ◽  
Vol 287 (1937) ◽  
pp. 20202189
Author(s):  
Mei Luo ◽  
Cédric Finet ◽  
Haosu Cong ◽  
Hong-yi Wei ◽  
Henry Chung
Keyword(s):  
Metal Binding ◽  
Model Organism ◽  
Low Complexity ◽  
Toxic Heavy Metals ◽  
Sequence Complexity ◽  
Heavy Metal Detoxification ◽  
History Of ◽  
Cysteine Content ◽  
Tandem Duplications ◽  
Unique Dataset

Metallothioneins (MTs) are a family of cysteine-rich metal-binding proteins that are important in the chelating and detoxification of toxic heavy metals. Until now, the short length and the low sequence complexity of MTs have hindered the inference of robust phylogenies, hampering the study of their evolution. To address this longstanding question, we applied an iterative BLAST search pipeline that allowed us to build a unique dataset of more than 300 MT sequences in insects. By combining phylogenetics and synteny analysis, we reconstructed the evolutionary history of MTs in insects. We show that the MT content in insects has been shaped by lineage-specific tandem duplications from a single ancestral MT. Strikingly, we also uncovered a sixth MT, MtnF, in the model organism Drosophila melanogaster . MtnF evolves faster than other MTs and is characterized by a non-canonical length and higher cysteine content. Our methodological framework not only paves the way for future studies on heavy metal detoxification but can also allow us to identify other previously unidentified genes and other low complexity genomic features.

scholarly journals The Evolution of Insect Metallothioneins

2020 ◽  
Author(s):  
Mei Luo ◽  
Cédric Finet ◽  
Haosu Cong ◽  
Hong-yi Wei ◽  
Henry Chung
Keyword(s):  
Metal Binding ◽  
Phylogenetic Reconstruction ◽  
Model Organism ◽  
Low Complexity ◽  
Toxic Heavy Metals ◽  
Heavy Metal Detoxification ◽  
History Of ◽  
Cysteine Content ◽  
Tandem Duplications ◽  
Unique Dataset

ABSTRACTMetallothioneins (MTs) are a family of cysteine-rich metal-binding proteins that are important in the chelating and detoxification of toxic heavy metals. Until now, the short length and the low sequence complexity of MTs has hindered the possibility of any phylogenetic reconstruction, hampering the study of their evolution. To answer this longstanding question, we developed an iterative BLAST search pipeline that allowed us to build a unique dataset of more than 300 MT sequences in insects. By combining phylogenetics and synteny analysis, we reconstructed the evolutionary history of MTs in insects. We show that the MT content in insects has been shaped by lineage-specific tandem duplications from a single ancestral MT. Strikingly, we also uncovered a sixth MT, MtnF, in the model organism Drosophila melanogaster. MtnF evolves faster than other MTs and is characterized by a non-canonical length and higher cysteine content. Our methodological framework not only paves the way for future studies on heavy metal detoxification but also can allow us to identify other previously unidentified genes and other low complexity genomic features.

Molecular breeding approaches for production of disease-resilient commercially important tobacco

2020 ◽  
Vol 19 (1) ◽  
pp. 10-25 ◽  
Author(s):  
Kaleem U Kakar ◽  
Zarqa Nawaz ◽  
Zhouqi Cui ◽  
Nazeer Ahemd ◽  
Xueliang Ren
Keyword(s):  
Molecular Breeding ◽  
Model Organism ◽  
Resistance Breeding ◽  
Underlying Disease ◽  
Molecular Techniques ◽  
Genetic Components ◽  
Global Presence ◽  
History Of ◽  
Commercially Important ◽  
Income Model

Abstract Tobacco is one of the most widely cultivated nonfood cash crops, a source of income, model organism for plant molecular research, a natural pesticide and of pharmaceutical importance. First domesticated in South Americas, the modern-day tobacco (Nicotiana tabacum) is now cultivated in more than 125 countries to generate revenues worth billions of dollars each year. However, the production of this crop is highly threatened by the global presence of devastating infectious agents, which cause huge fiscal loss. These threats have been battled through breeding for acquiring disease resilience in tobacco plants, first, via conventional and now with the use of modern molecular breeding approaches. For efficacy and precision, the characterization of the genetic components underlying disease resistance is the key tool in tobacco for resistance breeding programs. The past few decades have witnessed significant progress in resilience breeding through advanced molecular techniques. The current review discusses history of tobacco breeding since its time of origin till date, highlighting the most widely used techniques and recent advances in molecular research and strategies for resistance breeding. In addition, we narrate the budding possibilities for the future. This review will provide a comprehensive and valuable information for the tobacco growers and researchers to deal with the destructive infectious diseases.

scholarly journals Recurrent Collection of Drosophila melanogaster from Wild African Environments and Genomic Insights into Species History

2019 ◽  
Vol 37 (3) ◽  
pp. 627-638 ◽  
Author(s):  
Quentin D Sprengelmeyer ◽  
Suzan Mansourian ◽  
Jeremy D Lange ◽  
Daniel R Matute ◽  
Brandon S Cooper ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Demographic History ◽  
Central Africa ◽  
Model Organism ◽  
Sub Saharan Africa ◽  
Wilderness Areas ◽  
Southern Central ◽  
History Of ◽  
Sub Saharan ◽  
Improved Model

Abstract A long-standing enigma concerns the geographic and ecological origins of the intensively studied vinegar fly, Drosophila melanogaster. This globally distributed human commensal is thought to originate from sub-Saharan Africa, yet until recently, it had never been reported from undisturbed wilderness environments that could reflect its precommensal niche. Here, we document the collection of 288 D. melanogaster individuals from multiple African wilderness areas in Zambia, Zimbabwe, and Namibia. The presence of D. melanogaster in these remote woodland environments is consistent with an ancestral range in southern-central Africa, as opposed to equatorial regions. After sequencing the genomes of 17 wilderness-collected flies collected from Kafue National Park in Zambia, we found reduced genetic diversity relative to town populations, elevated chromosomal inversion frequencies, and strong differences at specific genes including known insecticide targets. Combining these genomes with existing data, we probed the history of this species’ geographic expansion. Demographic estimates indicated that expansion from southern-central Africa began ∼13,000 years ago, with a Saharan crossing soon after, but expansion from the Middle East into Europe did not begin until roughly 1,800 years ago. This improved model of demographic history will provide an important resource for future evolutionary and genomic studies of this key model organism. Our findings add context to the history of D. melanogaster, while opening the door for future studies on the biological basis of adaptation to human environments.

scholarly journals Genome Sequence of a Nephritogenic and Highly Transformable M49 Strain of Streptococcus pyogenes

2008 ◽  
Vol 190 (23) ◽  
pp. 7773-7785 ◽  
Author(s):  
W. Michael McShan ◽  
Joseph J. Ferretti ◽  
Tadahiro Karasawa ◽  
Alexander N. Suvorov ◽  
Shaoping Lin ◽  
...  
Keyword(s):  
Streptococcus Pyogenes ◽  
Group A Streptococcus ◽  
Genetic Material ◽  
Model Organism ◽  
Nudix Hydrolase ◽  
History Of ◽  
Group A ◽  
Short Palindromic Repeat ◽  
Post Streptococcal Glomerulonephritis ◽  
Type 3

ABSTRACT The 1,815,783-bp genome of a serotype M49 strain of Streptococcus pyogenes (group A streptococcus [GAS]), strain NZ131, has been determined. This GAS strain (FCT type 3; emm pattern E), originally isolated from a case of acute post-streptococcal glomerulonephritis, is unusually competent for electrotransformation and has been used extensively as a model organism for both basic genetic and pathogenesis investigations. As with the previously sequenced S. pyogenes genomes, three unique prophages are a major source of genetic diversity. Two clustered regularly interspaced short palindromic repeat (CRISPR) regions were present in the genome, providing genetic information on previous prophage encounters. A unique cluster of genes was found in the pathogenicity island-like emm region that included a novel Nudix hydrolase, and, further, this cluster appears to be specific for serotype M49 and M82 strains. Nudix hydrolases eliminate potentially hazardous materials or prevent the unbalanced accumulation of normal metabolites; in bacteria, these enzymes may play a role in host cell invasion. Since M49 S. pyogenes strains have been known to be associated with skin infections, the Nudix hydrolase and its associated genes may have a role in facilitating survival in an environment that is more variable and unpredictable than the uniform warmth and moisture of the throat. The genome of NZ131 continues to shed light upon the evolutionary history of this human pathogen. Apparent horizontal transfer of genetic material has led to the existence of highly variable virulence-associated regions that are marked by multiple rearrangements and genetic diversification while other regions, even those associated with virulence, vary little between genomes. The genome regions that encode surface gene products that will interact with host targets or aid in immune avoidance are the ones that display the most sequence diversity. Thus, while natural selection favors stability in much of the genome, it favors diversity in these regions.

The post-crisis Irish voter

2018 ◽  
Keyword(s):  
Party System ◽  
Party Systems ◽  
New Parties ◽  
The Great Recession ◽  
University Courses ◽  
National Election Study ◽  
History Of ◽  
Established Democracies ◽  
Unique Dataset ◽  
Cross National

This is the definitive study of the Irish general election of 2016 – the most dramatic election in a generation, which among other things resulted in the worst electoral outcome for Ireland’s established parties, the most fractionalized party system in the history of the state, and the emergence of new parties and groups, some of these of a ‘populist’ hue. This was one of the most volatile elections in Ireland (and among one of the most volatile elections in Europe), with among the lowest of election turnouts in the state’s history. These outcomes follow a pattern seen across a number of Western Europe’s established democracies in which the ‘deep crisis’ of the Great Recession has wreaked havoc on party systems. The objective of this book is to assess this most extraordinary of Irish elections both in its Irish and wider cross-national context. With contributions from leading scholars on Irish elections and parties, and using a unique dataset – the Irish National Election Study (INES) 2016 – this volume explores voting patterns at Ireland’s first post crisis election and it considers the implications for the electoral landscape and politics in Ireland. This book will be of interest to scholars of parties and elections. It should provide important supplementary reading to any university courses on Irish politics. And it should also be of interest to general readers interested in contemporary Irish affairs.

scholarly journals New Findings on Evolution of Metal Homeostasis Genes: Evidence from Comparative Genome Analysis of Bacteria and Archaea

2005 ◽  
Vol 71 (11) ◽  
pp. 7083-7091 ◽  
Author(s):  
J. M. Coombs ◽  
T. Barkay
Keyword(s):  
Metal Binding ◽  
Metal Homeostasis ◽  
Open Reading Frames ◽  
Minor Role ◽  
Gene Trees ◽  
New Findings ◽  
Atpase Gene ◽  
History Of ◽  
A Minor ◽  
Multiple Loss

ABSTRACT In order to examine the natural history of metal homeostasis genes in prokaryotes, open reading frames with homology to characterized PIB-type ATPases from the genomes of 188 bacteria and 22 archaea were investigated. Major findings were as follows. First, a high diversity in N-terminal metal binding motifs was observed. These motifs were distributed throughout bacterial and archaeal lineages, suggesting multiple loss and acquisition events. Second, the CopA locus separated into two distinct phylogenetic clusters, CopA1, which contained ATPases with documented Cu(I) influx activity, and CopA2, which contained both efflux and influx transporters and spanned the entire diversity of the bacterial domain, suggesting that CopA2 is the ancestral locus. Finally, phylogentic incongruences between 16S rRNA and PIB-type ATPase gene trees identified at least 14 instances of lateral gene transfer (LGT) that had occurred among diverse microbes. Results from bootstrapped supported nodes indicated that (i) a majority of the transfers occurred among proteobacteria, most likely due to the phylogenetic relatedness of these organisms, and (ii) gram-positive bacteria with low moles percent G+C were often involved in instances of LGT. These results, together with our earlier work on the occurrence of LGT in subsurface bacteria (J. M. Coombs and T. Barkay, Appl. Environ. Microbiol. 70:1698-1707, 2004), indicate that LGT has had a minor role in the evolution of PIB-type ATPases, unlike other genes that specify survival in metal-stressed environments. This study demonstrates how examination of a specific locus across microbial genomes can contribute to the understanding of phenotypes that are critical to the interactions of microbes with their environment.

scholarly journals Biology of Pseudomonas stutzeri

2006 ◽  
Vol 70 (2) ◽  
pp. 510-547 ◽  
Author(s):  
Jorge Lalucat ◽  
Antoni Bennasar ◽  
Rafael Bosch ◽  
Elena García-Valdés ◽  
Norberto J. Palleroni
Keyword(s):  
Natural Transformation ◽  
Model Organism ◽  
Pseudomonas Stutzeri ◽  
Opportunistic Pathogen ◽  
Denitrifying Bacterium ◽  
The Past ◽  
History Of ◽  
Metabolic Properties ◽  
Degradation Of Pollutants ◽  
Made In

SUMMARY Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from humans. Over the past 15 years, much progress has been made in elucidating the taxonomy of this diverse taxonomical group, demonstrating the clonality of its populations. The species has received much attention because of its particular metabolic properties: it has been proposed as a model organism for denitrification studies; many strains have natural transformation properties, making it relevant for study of the transfer of genes in the environment; several strains are able to fix dinitrogen; and others participate in the degradation of pollutants or interact with toxic metals. This review considers the history of the discovery, nomenclatural changes, and early studies, together with the relevant biological and ecological properties, of P. stutzeri.

scholarly journals Response of Chlorella Sp. to Nickel Pollution

1970 ◽  
Vol 25 (1) ◽  
pp. 129-139 ◽  
Author(s):  
Pawan Raj Shakya ◽  
D Kaplan
Keyword(s):  
Metal Binding ◽  
Binding Capacity ◽  
Low Cost ◽  
Preliminary Investigation ◽  
Resistance Mechanisms ◽  
Green Microalgae ◽  
Toxic Heavy Metals ◽  
Chemical Methods ◽  
Chlorella Sp ◽  
Physico Chemical

Unicellular green microalgae are widely used these days for removing toxic heavy metals from the contaminated environment by virtue of their metal binding capacities confirming resistance mechanisms. Besides, they have several advantages over conventional physico-chemical methods such as ion exchange, precipitation with CaCO3, adsorption, flocculation, etc. The present study is a preliminary investigation regarding an attempt to provide low cost, efficient and an emerging eco-friendly technology for the removal of nickel from the nickel polluted environemtn by the use of (WT) Chlorella sp. and one of the isolated cell lines, EMS-10 of the same species. Growth experiments show the effect of increasing NI2+ concentration on the WT and EMS-10 cultures. However, the ID50 value of the EMS-10 revealed some degree of resistance to nickel. Kinetic experiments reveal effective metal binding capacity in EMS-10 and demonstrated appreciable resistance in response to the nickel toxicity as compared to the WT.Key words: Green microalgae; Physico-chemical methods; EMS-10Tribhuvan University Journal Vol. XXV, No. 1, 2005Page:129-139Uploaded date: 26, September, 2010

scholarly journals Bioremoval of Different Heavy Metals in Industrial Effluent by the Resistant Fungal Strain Aspergillus niger

2021 ◽  
Vol 20 (4) ◽  
Author(s):  
K. J. Naveen Kumar ◽  
J. Prakash
Keyword(s):  
Heavy Metals ◽  
Aspergillus Niger ◽  
Metal Binding ◽  
Metal Removal ◽  
Low Cost ◽  
Heavy Metal Removal ◽  
Industrial Effluent ◽  
Toxic Metal ◽  
Differential Pulse ◽  
Toxic Heavy Metals

Developing countries are increasingly concerned with pollution due to toxic heavy metals in the environment. Unlike most organic pollutants which can be destroyed, toxic metal ions released into the environment often persist indefinitely circulating and eventually accumulating throughout the food chain thus posing a serious threat to mankind. The use of biological materials for heavy metal removal or recovery has gained importance in recent years due to their good performance and low cost. Among the various sources, both live and inactivated biomass of organisms exhibits interesting metal binding capacities. Their complex cell walls contain high content of functional groups like amino, amide, hydroxyl, carboxyl, and phosphate which have been implicated in metals binding. In the present study, Aspergillus niger was used to analyze the metal uptake from an aqueous solution. The determination of Cu+2, Pb+2, Cd+2, Zn+2, Co-2 and Ni+2 in samples was carried out by differential Pulse Anodic Voltammetry (DPASV) and the Voltammograms. Production of oxalic acid was carried out by submerged fermentation. The organism used in the present study has the ideal properties to sequester toxic metals and grow faster.

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