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1.
Ecol Evol ; 11(15): 10119-10132, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34367563

RESUMO

The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. Low genetic diversity and small effective population sizes (N e) are expected for narrow endemic species (NES). Conservation biology studies centered in a single species show some limitations, but they are still useful considering the limited time and resources available for protection of species at risk of extinction. Here, we evaluated the genetic diversity, population structure, N e, and minimum viable population (MVP) of I. cangae to provide information for effective conservation programs. Our analyses were based on 55 individuals collected from the Amendoim Lake and 35,638 neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and N e in the order of thousands, contrasting the expected for NES. Negative FIS values were also found, suggesting that I. cangae is not under risk of inbreeding depression. Our findings imply that I. cangae contains enough genetic diversity to ensure evolutionary potential and that all individuals should be treated as one demographic unit. These results provide essential information to optimize ex situ conservation efforts and genetic diversity monitoring, which are currently applied to guide I. cangae conservation plans.

2.
Microb Biotechnol ; 13(6): 1960-1971, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32812342

RESUMO

Accelerating microbial iron cycling is an innovative environmentally responsible strategy for mine remediation. In the present study, we extend the application of microbial iron cycling in environmental remediation, to include biocementation for the aggregation and stabilization of mine wastes. Microbial iron reduction was promoted monthly for 10 months in crushed canga (a by-product from iron ore mining, dominated by crystalline iron oxides) in 1 m3 containers. Ferrous iron concentrations reached 445 ppm in treatments and diverse lineages of the candidate phyla radiation dominated pore waters, implicating them in fermentation and/or metal cycling in this system. After a 6-month evaporation period, iron-rich cements had formed between grains and 20-cm aggregates were recoverable from treatments throughout the 1-m depth profile, while material from untreated and water-only controls remained unconsolidated. Canga-adapted plants seeded into one of the treatments germinated and grew well. Therefore, application of this geobiotechnology offers promise for stabilization of mine wastes, as well as re-formation of surface crusts that underpin unique and threatened plant ecosystems in iron ore regions.


Assuntos
Recuperação e Remediação Ambiental , Ferro , Cimentação , Ecossistema , Mineração
3.
Mitochondrial DNA B Resour ; 5(3): 3272-3273, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-33458136

RESUMO

We report the complete mitochondrial genome sequence of Glomeridesmus spelaeus, the first sequenced genome of the order Gomeridesmida. The genome is 14,825 pb in length and encodes 37 mitochondrial (13 PCGs, 2 rRNA genes, 22 tRNA) genes and contains a typical AT-rich region. The base composition of the mitogenome was A (40.1%), T (36.4%), C (15.8%), and G (7.6%), with an GC content of 23.5%. Our results indicated that G. spelaeus is only distantly related to the other Diplopoda species with available mitochondrial genomes in the public databases. As the broadest genetic characterization of a Glomeridesmida species available to date, the mitogenome of G. spelaeus will help understanding the evolution of such a little-known millipede group. Also, our data will be important for the characterization and conservation of the diverse invertebrate troglofauna of the Amazonian caves.

4.
PLoS One ; 13(8): e0201417, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30089144

RESUMO

Isoetes are ancient quillworts members of the only genus of the order Isoetales. The genus is slow evolving but is resilient, and widespread worldwide. Two recently described species occur in the Eastern Brazilian Amazon, Isoetes serracarajensis and Isoetes cangae. They are found in the ironstone grasslands known as Canga. While I. serracarajensis is present mostly in seasonal water bodies, I. cangae is known to occur in a single permanent lake at the South mountain range. In this work, we undertake an extensive morphological, physiological and genetic characterization of both species to establish species boundaries and better understand the morphological and genetic features of these two species. Our results indicate that the morphological differentiation of the species is subtle and requires a quantitative assessment of morphological elements of the megaspore for diagnosis. We did not detect differences in microspore output, but morphological peculiarities may establish a reproductive barrier. Additionally, genetic analysis using DNA barcodes and whole chloroplast genomes indicate that although the plants are genetically very similar both approaches provide diagnostic characters. There was no indication of population structuring I. serracarajensis. These results set the basis for a deeper understanding of the evolution of the Isoetes genus.


Assuntos
Código de Barras de DNA Taxonômico , Genoma de Cloroplastos , Lycopodiaceae , Lycopodiaceae/classificação , Lycopodiaceae/genética , Lycopodiaceae/crescimento & desenvolvimento , América do Sul
5.
BMC Bioinformatics ; 19(1): 297, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089465

RESUMO

BACKGROUND: Taxonomic identification of plants and insects is a hard process that demands expert taxonomists and time, and it's often difficult to distinguish on morphology only. DNA barcodes allow a rapid species discovery and identification and have been widely used for taxonomic identification by targeting known gene regions that permit to discriminate these species. DNA barcode sequence analysis is usually carried out with processes and tools that still demand a high interaction with the user or researcher. To reduce at most such interaction, we proposed PIPEBAR, a pipeline for DNA chromatograms analysis of Sanger platform sequencing, ensuring high quality consensus sequences along with efficient running time. We also proposed a paired-end reads assembly tool, OverlapPER, which is used in sequence or independently of PIPEBAR. RESULTS: PIPEBAR is a command line tool to automatize the processing of large number of trace files. It is accurate as the proprietary Geneious tool and faster than most popular software for barcoding analysis. It is 7 times faster than Geneious and 14 times faster than SeqTrace for processing hundreds of barcoding sequences. OverlapPER is a novel tool for overlapping paired-end reads accurately that accepts both substitution and indel errors and returns both overlapped and non-overlapped regions between a pair of reads. OverlapPER obtained the best results compared to currently used tools when merging 1,000,000 simulated paired-end reads. CONCLUSIONS: PIPEBAR and OverlapPER run on most operating systems and are freely available, along with supporting code and documentation, at https://sourceforge.net/projects/PIPEBAR / and https://sourceforge.net/projects/overlapper-reads /.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Software , Sequência de Bases , Códon de Terminação/genética , Sequência Consenso , Mutação da Fase de Leitura/genética
6.
Sci Rep ; 7(1): 7493, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790327

RESUMO

Amazon comprises a vast variety of ecosystems, including savannah-like Canga barrens that evolved on iron-lateritic rock plateaus of the Carajás Mountain range. Individual Cangas are enclosed by the rain forest, indicating insular isolation that enables speciation and plant community differentiation. To establish a framework for the research on natural history and conservation management of endemic Canga species, seven chloroplast DNA loci and an ITS2 nuclear DNA locus were used to study natural molecular variation of the red flowered Ipomoea cavalcantei and the lilac flowered I. marabaensis. Partitioning of the nuclear and chloroplast gene alleles strongly suggested that the species share the most recent common ancestor, pointing a new independent event of the red flower origin in the genus. Chloroplast gene allele analysis showed strong genetic differentiation between Canga populations, implying a limited role of seed dispersal in exchange of individuals between Cangas. Closed haplotype network topology indicated a requirement for the paternal inheritance in generation of cytoplasmic genetic variation. Tenfold higher nucleotide diversity in the nuclear ITS2 sequences distinguished I. cavalcantei from I. marabaensis, implying a different pace of evolutionary changes. Thus, Canga ecosystems offer powerful venues for the study of speciation, multitrait adaptation and the origins of genetic variation.


Assuntos
Adaptação Fisiológica/genética , DNA Intergênico/genética , Especiação Genética , Ipomoea/genética , Brasil , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Conservação dos Recursos Naturais , DNA de Cloroplastos/metabolismo , DNA de Cloroplastos/ultraestrutura , DNA Intergênico/química , DNA Intergênico/metabolismo , Variação Genética , Pradaria , Haplótipos , Ipomoea/classificação , Conformação de Ácido Nucleico , Filogenia , Células Vegetais/metabolismo , Células Vegetais/ultraestrutura , Floresta Úmida
7.
Genome Announc ; 4(3)2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27198020

RESUMO

Here, we present the draft genome sequence of the type strain of "Acidibacillus ferrooxidans," a mesophilic, heterotrophic, and acidophilic bacterium that was isolated from mine spoilage subjected to accelerated weathering in humidity cell tests carried out by the former U.S. Bureau of Mines in Salt Lake City, UT.

8.
Genome Announc ; 4(2)2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26988062

RESUMO

Here, we report the draft genome sequence of "Acidibacillus ferrooxidans" strain ITV01, a ferrous iron- and sulfide-mineral-oxidizing, obligate heterotrophic, and acidophilic bacterium affiliated with the phylum Firmicutes. Strain ITV01 was isolated from neutral drainage from a low-grade chalcopyrite from a mine in northern Brazil.

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