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Results for “Environmental DNA”

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At least 325 records · Page 18Linked to original sources
USGS1994

Flow cytometry for monitoring contaminant exposure in black-crowned night-herons

The flow cytometry method (FCM) was employed to determine cellular DNA content of black-crowned night-heron ( Nycticorax nycticorax ) embryos and 10-day-old chicks collected at sites differing in types of chemical contamination. The coefficient of variation of DNA content (CV) in blood collected from embryos suggested cytogenetic damage at a site in Louisiana known to be contaminated with petroleum. Blood CV from chicks suggested genetic damage at a site in Texas also known to be contaminated with petroleum. Spleen CVs in chicks were significantly lower than respective means from the reference site. The CVs of chick blood and liver and spleen negatively correlated, suggesting recovery of spleen and liver cells after exposure to a clastogenic compound. Thus, the lower CVs may also have been indicative of genetic damage. Based on the findings of this study, FCM is a potential indicator of certain environmental contaminants in black-crowned night-herons.

Archives of Environmental Contamination and Toxico↗
USGS2022

Millennia-old coral holobiont DNA provides insight into future adaptive trajectories

Ancient DNA (aDNA) has been applied to evolutionary questions across a wide variety of taxa. Here, for the first time, we leverage aDNA from millennia-old fossil coral fragments to gain new insights into a rapidly declining western Atlantic reef ecosystem. We sampled four Acropora palmata fragments (dated 4215 BCE - 1099 CE) obtained from two Florida Keys reef cores. From these samples, we established that it is possible both to sequence ancient DNA from reef cores and place the data in the context of modern-day genetic variation. We recovered varying amounts of nuclear DNA exhibiting the characteristic signatures of aDNA from the A. palmata fragments. To describe the holobiont sensu lato, which plays a crucial role in reef health, we utilized metagenome-assembled genomes as a reference to identify a large additional proportion of ancient microbial DNA from the samples. The samples shared many common microbes with modern-day coral holobionts from the same region, suggesting remarkable holobiont stability over time. Despite efforts, we were unable to recover ancient Symbiodiniaceae reads from the samples. Comparing the ancient A. palmata data to whole-genome sequencing data from living acroporids, we found that while slightly distinct, ancient samples were most closely related to individuals of their own species. Together, these results provide a proof-of-principle showing that it is possible to carry out direct analysis of coral holobiont change over time, which lays a foundation for studying the impacts of environmental stress and evolutionary constraints.

Molecular Ecology↗
USGS2013

Multi-laboratory evaluations of the performance of Catellicoccus marimammalium PCR assays developed to target gull fecal sources

Here we report results from a multi-laboratory ( n = 11) evaluation of four different PCR methods targeting the 16S rRNA gene of Catellicoccus marimammalium originally developed to detect gull fecal contamination in coastal environments. The methods included a conventional end-point PCR method, a SYBR ® Green qPCR method, and two TaqMan ® qPCR methods. Different techniques for data normalization and analysis were tested. Data analysis methods had a pronounced impact on assay sensitivity and specificity calculations. Across-laboratory standardization of metrics including the lower limit of quantification (LLOQ), target detected but not quantifiable (DNQ), and target not detected (ND) significantly improved results compared to results submitted by individual laboratories prior to definition standardization. The unit of measure used for data normalization also had a pronounced effect on measured assay performance. Data normalization to DNA mass improved quantitative method performance as compared to enterococcus normalization. The MST methods tested here were originally designed for gulls but were found in this study to also detect feces from other birds, particularly feces composited from pigeons. Sequencing efforts showed that some pigeon feces from California contained sequences similar to C. marimammalium found in gull feces. These data suggest that the prevalence, geographic scope, and ecology of C. marimammalium in host birds other than gulls require further investigation. This study represents an important first step in the multi-laboratory assessment of these methods and highlights the need to broaden and standardize additional evaluations, including environmentally relevant target concentrations in ambient waters from diverse geographic regions.

Water Research↗
USGS2020

Spatial segregation of cisco (Coregonus artedi) and lake whitefish (C. clupeaformis) larvae in Chaumont Bay, Lake Ontario

Abstract Two of the remaining coregonine species in Lake Ontario, cisco (Coregonus artedi) and lake whitefish (C. clupeaformis), spawn in Chaumont Bay, NY. Larvae co-occur in the spring but are difficult to distinguish morphologically. We applied genetic species identification using microsatellite DNA loci of 268 larvae from known locations in nearshore and offshore habitats in Chaumont Bay to determine the extent of mixing of these species in each habitat. Cisco dominated (95% of larvae) the larvae in offshore habitats and lake whitefish dominated (84%) in nearshore habitats, where seven of eight putative hybrids occurred. Habitat segregation between these two species at the larval stage has implications for productivity estimates. Discrimination between cisco and lake whitefish larvae helps to characterize habitat and basic life history needs and to focus research collections. Genetic species identification should be applied to larger samples of larvae to evaluate changes in larval distributions and associations with environmental conditions.

Chaumont Bay↗
USGS2016

Chesapeake Bay fish–osprey ( Pandion haliaetus ) food chain: Evaluation of contaminant exposure and genetic damage

From 2011 to 2013, a large-scale ecotoxicological study was conducted in several Chesapeake Bay (USA) tributaries (Susquehanna River and flats, the Back, Baltimore Harbor/Patapsco Rivers, Anacostia/ middle Potomac, Elizabeth and James Rivers) and Poplar Island as a mid-Bay reference site. Osprey ( Pandion haliaetus ) diet and the transfer of contaminants from fish to osprey eggs were evaluated. The most bioaccumulative compounds (biomagnification factor > 5) included p,p′ -dichlorodiphenyldichloroethylene (DDE), total polychlorinated biphenyls (PCBs), total polybrominated diphenyl ethers (PBDEs), and bromodiphenyl ether (BDE) congeners 47, 99, 100, and 154. This analysis suggested that alternative brominated flame retardants and other compounds (methoxytriclosan) are not appreciably biomagnifying. A multivariate analysis of similarity indicated that major differences in patterns among study sites were driven by PCB congeners 105, 128, 156, 170/190, and 189, and PBDE congeners 99 and 209. An integrative redundancy analysis showed that osprey eggs from Baltimore Harbor/Patapsco River and the Elizabeth River had high residues of PCBs and p,p ′-DDE, with PBDEs making a substantial contribution to overall halogenated contamination on the Susquehanna and Anacostia/middle Potomac Rivers. The redundancy analysis also suggested a potential relation between PBDE residues in osprey eggs and oxidative DNA damage in nestling blood samples. The results also indicate that there is no longer a discernible relation between halogenated contaminants in osprey eggs and their reproductive success in Chesapeake Bay. Osprey populations are thriving in much of the Chesapeake, with productivity rates exceeding those required to sustain a stable population.

Chesapeake Bay↗
USGS2022

Subspecies differentiation and range-wide genetic structure are driven by climate in the California gnatcatcher, a flagship species for coastal sage scrub conservation

Understanding genetic structure and diversity within species can uncover associations with environmental and geographic attributes that highlight adaptive potential and inform conservation and management. The California gnatcatcher, Polioptila californica , is a small songbird found in desert and coastal scrub habitats from the southern end of Baja California Sur to Ventura County, California. Lack of congruence among morphological subspecies hypotheses and lack of measurable genetic structure found in a few genetic markers led to questions about the validity of subspecies within P. californica and the listing status of the coastal California gnatcatcher, P. c. californica . As a U.S. federally threatened subspecies, P. c. californica is recognized as a flagship for coastal sage scrub conservation throughout southern California. We used restriction site-associated DNA sequencing to develop a genomic dataset for the California gnatcatcher. We sampled throughout the species' range, examined genetic structure, gene–environment associations, and demographic history, and tested for concordance between genetic structure and morphological subspecies groups. Our data support two distinct genetic groups with evidence of restricted movement and gene flow near the U.S.- Mexico international border. We found that climate-associated outlier loci were more strongly differentiated than climate neutral loci, suggesting that local climate adaptation may have helped to drive differentiation after Holocene range expansions. Patterns of habitat loss and fragmentation are also concordant with genetic substructure throughout the southern California portion of the range. Finally, our genetic data supported the morphologically defined P. c. californica as a distinct group, but there was little evidence of genetic differentiation among other previously hypothesized subspecies in Baja California. Our data suggest that retaining and restoring connectivity, and protecting populations, particularly at the northern range edge, could help preserve existing adaptive potential to allow for future range expansion and long-term persistence of the California gnatcatcher.

California↗
USGS2012

Identification of functionally active aerobic methanotrophs in sediments from an arctic lake using stable isotope probing

Arctic lakes are a significant source of the greenhouse gas methane (CH 4 ), but the role that methane oxidizing bacteria (methanotrophs) play in limiting the overall CH 4 flux is poorly understood. Here, we used stable isotope probing (SIP) techniques to identify the metabolically active aerobic methanotrophs in upper sediments (0–1 cm) from an arctic lake in northern Alaska sampled during ice-free summer conditions. The highest CH 4 oxidation potential was observed in the upper sediment (0–1 cm depth) with 1.59 μmol g wet weight -1 day -1 compared with the deeper sediment samples (1–3 cm, 3–5 cm and 5–10 cm), which exhibited CH 4 oxidation potentials below 0.4 μmol g wet weight -1 day -1 . Both type I and type II methanotrophs were directly detected in the upper sediment total communities using targeted primer sets based on 16S rRNA genes. Sequencing of 16S rRNA genes and functional genes ( pmoA and mxaF ) in the 13 C-DNA from the upper sediment indicated that type I methanotrophs, mainly Methylobacter, Methylosoma, Methylomonas and Methylovulum miyakonense, dominated the assimilation of CH 4 . Methylotrophs, including the genera Methylophilus and/or Methylotenera, were also abundant in the 13 CDNA. Our results show that a diverse microbial consortium acquired carbon from CH 4 in the sediments of this arctic lake.

Alaska↗
USGS2017

DNA-based detection of the fungal pathogen Geomyces destructans in soil from bat hibernacula

White-nose syndrome (WNS) is an emerging disease causing unprecedented morbidity and mortality among bats in eastern North America. The disease is characterized by cutaneous infection of hibernating bats by the psychrophilic fungus Geomyces destructans . Detection of G. destructans in environments occupied by bats will be critical for WNS surveillance, management and characterization of the fungal lifecycle. We initiated an rRNA gene region-based molecular survey to characterize the distribution of G. destructans in soil samples collected from bat hibernacula in the eastern United States with an existing PCR test. Although this test did not specifically detect G. destructans in soil samples based on a presence/absence metric, it did favor amplification of DNA from putative Geomyces species. Cloning and sequencing of PCR products amplified from 24 soil samples revealed 74 unique sequence variants representing 12 clades. Clones with exact sequence matches to G. destructans were identified in three of 19 soil samples from hibernacula in states where WNS is known to occur. Geomyces destructans was not identified in an additional five samples collected outside the region where WNS has been documented. This study highlights the diversity of putative Geomyces spp. in soil from bat hibernacula and indicates that further research is needed to better define the taxonomy of this genus and to develop enhanced diagnostic tests for rapid and specific detection of G. destructans in environmental samples.

Connecticut, Indiana, Kentucky, Massachusetts, Min↗
USGS1997

Population genetic studies of the polar bear ( Ursus maritimus ): A summary of available data and interpretation of results

A summary of existing population genetics literature is presented for polar bears ( Ursus maritimus ) and interpreted in the context of the species' life-history characteristics and regional heterogeneity in environmental regimes and movement patterns. Several nongenetic data sets including morphology, contaminant levels, geographic variation in reproductive characteristics, and the location and distribution of open-water foraging habitat suggest some degree of spatial structuring. Eleven populations are recognized by the IUCN Polar Bear Specialist Group. Few genetics studies exist for polar bears. Interpretation and generalizations of regional variation in intra- and interpopulation levels of genetic variability are confounded by the paucity of data from many regions and by the fact that no single informative genetic marker has been employed in multiple regions. Early allozyme studies revealed comparatively low levels of genetic variability and no compelling evidence of spatial structuring. Studies employing mitochondrial DNA (mtDNA) also found low levels of genetic variation, a lack of phylogenetic structure, and no significant evidence for spatial variation in haplotype frequency. In contrast, microsatellite variable number of tandem repeat (VNTR) loci have revealed significant heterogeneity in allele frequency among populations in the Canadian Arctic. These regions are characterized by archipelgic patterns of sea-ice movements. Further studies using highly polymorphic loci are needed in regions characterized by greater polar bear dependency on pelagic sea-ice movements and in regions for which no data currently exist (i.e., Laptev and Novaya Zemlya/Franz Josef).

Book chapter↗
USGS2000

Mixed-function oxygenases, oxidative stress, and chromosomal damage measured in lesser scaup wintering on the Indiana Harbor Canal

During the winter of 1993-1994, male lesser scaup ( Aythya alfinis ) were collected on the heavily polluted Indiana Harbor Canal, East Chicago, Indiana, and examined for several bioindicators of chemical exposure. Livers were analyzed for activities of three cytochrome P450-associated monooxygenases and four measures of oxidative stress. Blood and spleen were analyzed by flow cytometry for chromosomal damage. In a concurrent study, scaup tissues were analyzed for organic and inorganic contaminants. Ethoxyresomfm-O-dealkylase (EROD) activity in livers of scaup collected in January 1994 was significantly higher than in livers of scaup collected in March 1994 or in livers of reference birds. Three hepatic monooxygenase activities were each significantly correlated with polycyclic aromatic hydrocarbon (PAH) concentrations in scaup carcasses. Thiobarbituric acid (TBA) activity in scaup livers was positively correlated with iron, boron, and lead concentrations in livers and polychlorinated biphenyl concentrations in carcasses. TBA activity was negatively correlated with protein-bound thiol activity and mercury concentrations in livers. The coefficient of variation of DNA content in scaup blood cells was correlated with PAH concentrations in scaup carcasses. This is the first field study with birds to demonstrate a correlation between liver monooxygenase activity and carcass PAH concentrations and to show a direct correlation between PAH concentrations in tissues and somatic chromosomal damage in blood.

Indiana↗
USGS2023

DNA metabarcoding-based evaluation of the diet of Big Brown Bats (Eptesicus fuscus) in the Mid-Atlantic region

High-throughput DNA sequencing can generate large genetic datasets in a cost-effective manner. Although the diet of Eptesicus fuscus (Big Brown Bat) has been studied widely in natural and rural systems using visual identification of prey items in feces, our aim was to more completely assess diet using a metabarcoding approach across a wide urban–natural landscape gradient in the mid-Atlantic region. Concordant with our expectations and previous Big Brown Bat diet studies from visual identification, we observed a high abundance of Coleoptera (beetles) relative to other insect orders. Although a possible improvement over visual techniques for studying food habits, we suggest caution in interpreting metabarcoding results in diet studies. We noted observations of environmental or contaminant taxa within these data, and designed a stringent filtering method that we used to eliminate these taxa, but that also removed previously documented prey taxa from our dataset.

Maryland, Pennsylvania, Virginia, West Virginia↗
USGS2023

Conservation genomics of an endangered montane amphibian reveals low population structure, low genomic diversity and selection pressure from disease

Wildlife diseases are a major global threat to biodiversity. Boreal toads ( Anaxyrus [Bufo] boreas ) are a state-endangered species in the southern Rocky Mountains of Colorado and New Mexico, and a species of concern in Wyoming, largely due to lethal skin infections caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis ( Bd ). We performed conservation and landscape genomic analyses using single nucleotide polymorphisms from double-digest, restriction site-associated DNA sequencing in combination with the development of the first boreal toad (and first North American toad) reference genome to investigate population structure, genomic diversity, landscape connectivity and adaptive divergence. Genomic diversity ( π = 0.00034–0.00040) and effective population sizes ( N e = 8.9–38.4) were low, likely due to post-Pleistocene founder effects and Bd -related population crashes over the last three decades. Population structure was also low, likely due to formerly high connectivity among a higher density of geographically proximate populations. Boreal toad gene flow was facilitated by low precipitation, cold minimum temperatures, less tree canopy, low heat load and less urbanization. We found >8X more putatively adaptive loci related to Bd intensity than to all other environmental factors combined, and evidence for genes under selection related to immune response, heart development and regulation and skin function. These data suggest boreal toads in habitats with Bd have experienced stronger selection pressure from disease than from other, broad-scale environmental variations. These findings can be used by managers to conserve and recover the species through actions including reintroduction and supplementation of populations that have declined due to Bd .

Colorado↗
USGS1987

Toxicity of paraquat in nestling birds: effects on plasma and tissue biochemistry in American kestrels

Beginning the day after hatching, American kestrel ( Falco sparverius ) nestlings were orally dosed daily for 10 days with 5 μL/g of distilled water (controls), 10 mg/kg, 25 mg/kg, or 60 mg/kg of paraquat dichloride (1,1′-dimethyl-4,4′-bipyridinium dichloride) in distilled water. Forty-four percent of the nestlings receiving 60 mg/kg died after 4 days. Plasma LDH activity and total protein concentration were elevated, and plasma alkaline phosphatase activity was lower in survivors of the 60 mg/kg group at 10 days. Lung total sulfhydryl (TSH) and protein-bound sulfhydryl (PBSH) concentrations were significantly higher in the 10 mg/kg, 25 mg/kg, or 60 mg/kg groups. Lung DNA, RNA, protein, and hydroxyproline (collagen) concentrations were not significantly affected by treatment. Liver NPSH was lower in the 60 mg/kg group while liver glycogen concentration was not affected by treatment. Kidney DNA, RNA, and RNA to protein concentration ratio were higher in the 25 mg/kg or 60 mg/kg groups. These findings in combination with recently reported effects on growth and histopathology suggest that altricial nestling kestrels are more sensitive to paraquat exposure than young or adult birds of precocial species. From a comparative viewpoint, lungs of nestling kestrels are less sensitive to paraquat than mammalian lungs.

Maryland↗
USGS2008

Real-time PCR detection and quantification of nine potential sources of fecal contamination by analysis of mitochondrial Cytochrome b targets

We designed and tested real-time PCR probe/primer sets to detect and quantify Cytochrome b sequences of mitochondrial DNA (mtDNA) from nine vertebrate species of pet (dog), farm (cow, chicken, sheep, horse, pig), wildlife (Canada goose, white-tailed deer), and human. Linear ranges of the assays were from 101 to 108 copies/??l. To formally test the performance of the assays, twenty blinded fecal suspension samples were analyzed by real-time PCR to identify the source of the feces. Sixteen of the twenty samples were correctly and unambiguously identified. Average sensitivity was calculated to be 0.850, while average specificity was found to be 0.994. One beef cow sample was not detected, but mtDNA from 11 other beef cattle of both sexes and varying physiological states was found in concentrations similar (3.45 ?? 107 copies/g) to thatfound in human feces (1.1 ?? 107 copies/g). Thus, environmental conditions and sample handling are probably important factors for successful detection of fecal mtDNA. When sewage samples were analyzed, only human mtDNA (7.2 ?? 104 copies/100 mL) was detected. With a detection threshold of 250 copies/reaction, an efficient concentration and purification method resulted in a final detection limit for human feces of 1.8 mg/100 mL water.

Environmental Science & Technology↗
USGS1994

Use of molecular techniques to evaluate the survival of a microorganism injected into an aquifer

A PCR primer set and an internal probe that are specific for Pseudomonas sp. strain B13, a 3-chlorobenzoate-metabolizing strain, were developed. Using this primer set and probe, we were able to detect Pseudomonas sp. strain B13 DNA sequences in DNA extracted from aquifer samples 14.5 months after Pseudomonas sp. strain B13 had been injected into a sand and gravel aquifer. This primer set and probe were also used to analyze isolates from 3-chlorobenzoate enrichments of the aquifer samples by Southern blot analysis. Hybridization of Southern blots with the Pseudomonas sp. strain B13-specific probe and a catabolic probe in conjunction with restriction fragment length polymorphism (RFLP) analysis of ribosome genes was used to determine that viable Pseudomonas sp. strain B13 persisted in this environment. We isolated a new 3-chlorobenzoate-degrading strain from one of these enrichment cultures. The B13-specific probe does not hybridize to DNA from this isolate. The new strain could be the result of gene exchange between Pseudomonas sp. strain B13 and an indigenous bacterium. This speculation is based on an RFLP pattern of ribosome genes that differs from that of Pseudomonas sp. strain B13, the fact that identically sized restriction fragments hybridized to the catabolic gene probe, and the absence of any enrichable 3-chlorobenzoate-degrading strains in the aquifer prior to inoculation.

Massachusetts↗
USGS2013

Performance of human fecal anaerobe-associated PCR-based assays in a multi-laboratory method evaluation study

A number of PCR-based methods for detecting human fecal material in environmental waters have been developed over the past decade, but these methods have rarely received independent comparative testing in large multi-laboratory studies. Here, we evaluated ten of these methods (BacH, BacHum-UCD, Bacteroides thetaiotaomicron (BtH), BsteriF1, gyrB, HF183 endpoint, HF183 SYBR, HF183 Taqman®, HumM2, and Methanobrevibacter smithii nifH (Mnif)) using 64 blind samples prepared in one laboratory. The blind samples contained either one or two fecal sources from human, wastewater or non-human sources. The assay results were assessed for presence/absence of the human markers and also quantitatively while varying the following: 1) classification of samples that were detected but not quantifiable (DNQ) as positive or negative; 2) reference fecal sample concentration unit of measure (such as culturable indicator bacteria, wet mass, total DNA, etc); and 3) human fecal source type (stool, sewage or septage). Assay performance using presence/absence metrics was found to depend on the classification of DNQ samples. The assays that performed best quantitatively varied based on the fecal concentration unit of measure and laboratory protocol. All methods were consistently more sensitive to human stools compared to sewage or septage in both the presence/absence and quantitative analysis. Overall, HF183 Taqman® was found to be the most effective marker of human fecal contamination in this California-based study.

Water Research↗
USGS2016

Nuclear and mitochondrial DNA analyses of golden eagles (Aquila chrysaetos canadensis) from three areas in western North America; initial results and conservation implications

Understanding the genetics of a population is a critical component of developing conservation strategies. We used archived tissue samples from golden eagles ( Aquila chrysaetos canadensis ) in three geographic regions of western North America to conduct a preliminary study of the genetics of the North American subspecies, and to provide data for United States Fish and Wildlife Service (USFWS) decision-making for golden eagle management. We used a combination of mitochondrial DNA (mtDNA) D-loop sequences and 16 nuclear DNA (nDNA) microsatellite loci to investigate the extent of gene flow among our sampling areas in Idaho, California and Alaska and to determine if we could distinguish birds from the different geographic regions based on their genetic profiles. Our results indicate high genetic diversity, low genetic structure and high connectivity. Nuclear DNA Fst values between Idaho and California were low but significantly different from zero (0.026). Bayesian clustering methods indicated a single population, and we were unable to distinguish summer breeding residents from different regions. Results of the mtDNA AMOVA showed that most of the haplotype variation (97%) was within the geographic populations while 3% variation was partitioned among them. One haplotype was common to all three areas. One region-specific haplotype was detected in California and one in Idaho, but additional sampling is required to determine if these haplotypes are unique to those geographic areas or a sampling artifact. We discuss potential sources of the high gene flow for this species including natal and breeding dispersal, floaters, and changes in migratory behavior as a result of environmental factors such as climate change and habitat alteration. Our preliminary findings can help inform the USFWS in development of golden eagle management strategies and provide a basis for additional research into the complex dynamics of the North American subspecies.

Alaska, California, Idaho, Oregon↗
USGS2017

Bacteria versus selenium: A view from the inside out

Bacteria and selenium (Se) are closely interlinked as the element serves both essential nutrient requirements and energy generation functions. However, Se can also behave as a powerful toxicant for bacterial homeostasis. Conversely, bacteria play a tremendous role in the cycling of Se between different environmental compartments, and bacterial metabolism has been shown to participate to all valence state transformations undergone by Se in nature. Bacteria possess an extensive molecular repertoire for Se metabolism. At the end of the 1980s, a novel mode of anaerobic respiration based on Se oxyanions was experimentally documented for the first time. Following this discovery, specific enzymes capable of reducing Se oxyanions and harvesting energy were found in a number of anaerobic bacteria. The genes involved in the expression of these enzymes have later been identified and cloned. This iterative approach undertaken outside-in led to the understanding of the molecular mechanisms of Se transformations in bacteria. Based on the extensive knowledge accumulated over the years, we now have a full(er) view from the inside out , from DNA-encoding genes to enzymes and thermodynamics. Bacterial transformations of Se for assimilatory purposes have been the object of numerous studies predating the investigation of Se respiration. Remarkable contributions related to the understating of the molecular picture underlying seleno-amino acid biosynthesis are reviewed herein. Under certain circumstances, Se is a toxicant for bacterial metabolism and bacteria have evolved strategies to counteract this toxicity, most notably by the formation of elemental Se (nano)particles. Several biotechnological applications, such as the production of functional materials and the biofortification of crop species using Se-utilizing bacteria, are presented in this chapter.

Book chapter↗