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Gamiz-Arco G, Risso VA, Gaucher EA, Gavira JA, Naganathan AN, Ibarra-Molero B, Sanchez-Ruiz JM. Combining Ancestral Reconstruction with Folding-Landscape Simulations to Engineer Heterologous Protein Expression. J Mol Biol 2021; 433:167321. [PMID: 34687715 DOI: 10.1016/j.jmb.2021.167321] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/01/2021] [Accepted: 10/17/2021] [Indexed: 11/30/2022]
Abstract
Obligate symbionts typically exhibit high evolutionary rates. Consequently, their proteins may differ considerably from their modern and ancestral homologs in terms of both sequence and properties, thus providing excellent models to study protein evolution. Also, obligate symbionts are challenging to culture in the lab and proteins from uncultured organisms must be produced in heterologous hosts using recombinant DNA technology. Obligate symbionts thus replicate a fundamental scenario of metagenomics studies aimed at the functional characterization and biotechnological exploitation of proteins from the bacteria in soil. Here, we use the thioredoxin from Candidatus Photodesmus katoptron, an uncultured symbiont of flashlight fish, to explore evolutionary and engineering aspects of protein folding in heterologous hosts. The symbiont protein is a standard thioredoxin in terms of 3D-structure, stability and redox activity. However, its folding outside the original host is severely impaired, as shown by a very slow refolding in vitro and an inefficient expression in E. coli that leads mostly to insoluble protein. By contrast, resurrected Precambrian thioredoxins express efficiently in E. coli, plausibly reflecting an ancient adaptation to unassisted folding. We have used a statistical-mechanical model of the folding landscape to guide back-to-ancestor engineering of the symbiont protein. Remarkably, we find that the efficiency of heterologous expression correlates with the in vitro (i.e., unassisted) folding rate and that the ancestral expression efficiency can be achieved with only 1-2 back-to-ancestor replacements. These results demonstrate a minimal-perturbation, sequence-engineering approach to rescue inefficient heterologous expression which may potentially be useful in metagenomics efforts targeting recent adaptations.
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Affiliation(s)
- Gloria Gamiz-Arco
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Valeria A Risso
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain
| | - Eric A Gaucher
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA
| | - Jose A Gavira
- Laboratorio de Estudios Cristalograficos, Instituto Andaluz de Ciencias de la Tierra, CSIC, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, Avenida de las Palmeras 4, Armilla, Granada 18100, Spain. https://twitter.com/Gavirius
| | - Athi N Naganathan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India.
| | - Beatriz Ibarra-Molero
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain.
| | - Jose M Sanchez-Ruiz
- Departamento de Quimica Fisica, Facultad de Ciencias, Unidad de Excelencia de Quimica Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain.
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Acquisition of bioluminescent trait by non-luminous organisms from luminous organisms through various origins. Photochem Photobiol Sci 2021; 20:1547-1562. [PMID: 34714534 DOI: 10.1007/s43630-021-00124-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 10/20/2021] [Indexed: 12/20/2022]
Abstract
Bioluminescence is a natural light emitting phenomenon that occurs due to a chemical reaction between luciferin and luciferase. It is primarily an innate and inherited trait in most terrestrial luminous organisms. However, most luminous organisms produce light in the ocean by acquiring luminous symbionts, luciferin (substrate), and/or luciferase (enzyme) through various transmission pathways. For instance, coelenterazine, a well-known luciferin, is obtained by cnidarians, crustaceans, and deep-sea fish through multi-level dietary linkages from coelenterazine producers such as ctenophores, decapods, and copepods. In contrast, some non-luminous Vibrio bacteria became bioluminescent by obtaining lux genes from luminous Vibrio species by horizontal gene transfer. Various examples detailed in this review show how non-luminescent organisms became luminescent by acquiring symbionts, dietary luciferins and luciferases, and genes. This review highlights three modes (symbiosis, ingestion, and horizontal gene transfer) that allow organisms lacking genes for autonomous bioluminescent systems to obtain the ability to produce light. In addition to bioluminescence, this manuscript discusses the acquisition of other traits such as pigments, fluorescence, toxins, and others, to infer the potential processes of acquisition.
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Ghedotti MJ, DeKay HM, Maile AJ, Smith WL, Davis MP. Anatomy and evolution of bioluminescent organs in the slimeheads (Teleostei: Trachichthyidae). J Morphol 2021; 282:820-832. [PMID: 33733466 DOI: 10.1002/jmor.21349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/11/2021] [Accepted: 03/14/2021] [Indexed: 11/10/2022]
Abstract
Bacterial bioluminescent organs in fishes have a diverse range of tissues of origin, patterns of compartmentalization, and associated light-conducting structures. The morphology of the perianal, bacterial bioluminescent organ of Aulotrachichthys prosthemius was described previously, but the light organ in other species of slimeheads, family Trachichthyidae, is poorly known. Here, we describe the anatomy of the bioluminescent organs in trachichthyids and places the evolution of this light-producing system in the context of a new phylogeny of the Trachichthyoidei to test the hypothesis that bioluminescence evolved twice in the suborder and that the light-producing component derives from the perianal ectoderm. We use gross and histological examination to provide the first description of the bioluminescent organ of Paratrachichthys and four additional species of Aulotrachichthys. Observations also strongly suggest the presence of a perianal bioluminescent organ in Sorosichthys ananasa. The updated phylogeny of the Trachichthyoidei is the first to combine morphological and DNA-sequence (11-gene fragments) evidence, and supports a monophyletic Trachichthyidae with component subfamilies Hoplostethinae and Trachichthyinae, supporting continued recognition of the family Anoplogastridae. All bioluminescent trachichthyoids share a similar bioluminescent-organ structure with elongate chambers filled with bacteria and connected to collecting ducts that, in turn, connect to superficial ducts that lead to and have lining epithelia continuous with the epidermis. In the context of the phylogeny, the bioluminescent organ of trachichthyids is inferred to have evolved as an elaboration of the proctodeum in the ancestor of Aulotrachichthys, Paratrachichthys, and Sorosichthys independently from the structurally similar cephalic bioluminescent organs in Anomalopidae and Monocentridae.
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Affiliation(s)
- Michael J Ghedotti
- Department of Biology, Regis University, Denver, Colorado, USA.,Bell Museum of Natural History, University of Minnesota, St. Paul, Minnesota, USA
| | - Hannah M DeKay
- Department of Biology, Regis University, Denver, Colorado, USA
| | - Alex J Maile
- Department of Biological Sciences, St. Cloud State University, St. Cloud, Minnesota, USA
| | - W Leo Smith
- Department of Ecology and Evolutionary Biology and Biodiversity Institute, University of Kansas, Lawrence, Kansas, USA
| | - Matthew P Davis
- Department of Biological Sciences, St. Cloud State University, St. Cloud, Minnesota, USA
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Oren A, Garrity GM, Parker CT, Chuvochina M, Trujillo ME. Lists of names of prokaryotic Candidatus taxa. Int J Syst Evol Microbiol 2020; 70:3956-4042. [DOI: 10.1099/ijsem.0.003789] [Citation(s) in RCA: 782] [Impact Index Per Article: 195.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
We here present annotated lists of names of Candidatus taxa of prokaryotes with ranks between subspecies and class, proposed between the mid-1990s, when the provisional status of Candidatus taxa was first established, and the end of 2018. Where necessary, corrected names are proposed that comply with the current provisions of the International Code of Nomenclature of Prokaryotes and its Orthography appendix. These lists, as well as updated lists of newly published names of Candidatus taxa with additions and corrections to the current lists to be published periodically in the International Journal of Systematic and Evolutionary Microbiology, may serve as the basis for the valid publication of the Candidatus names if and when the current proposals to expand the type material for naming of prokaryotes to also include gene sequences of yet-uncultivated taxa is accepted by the International Committee on Systematics of Prokaryotes.
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Affiliation(s)
- Aharon Oren
- The Institute of Life Sciences, The Hebrew University of Jerusalem, The Edmond J. Safra Campus, 9190401 Jerusalem, Israel
| | - George M. Garrity
- NamesforLife, LLC, PO Box 769, Okemos MI 48805-0769, USA
- Department of Microbiology & Molecular Genetics, Biomedical Physical Sciences, Michigan State University, East Lansing, MI 48824-4320, USA
| | | | - Maria Chuvochina
- Australian Centre for Ecogenomics, University of Queensland, St. Lucia QLD 4072, Brisbane, Australia
| | - Martha E. Trujillo
- Departamento de Microbiología y Genética, Campus Miguel de Unamuno, Universidad de Salamanca, 37007, Salamanca, Spain
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Baker LJ, Freed LL, Easson CG, Lopez JV, Fenolio D, Sutton TT, Nyholm SV, Hendry TA. Diverse deep-sea anglerfishes share a genetically reduced luminous symbiont that is acquired from the environment. eLife 2019; 8:47606. [PMID: 31571583 PMCID: PMC6773444 DOI: 10.7554/elife.47606] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/21/2019] [Indexed: 11/13/2022] Open
Abstract
Deep-sea anglerfishes are relatively abundant and diverse, but their luminescent bacterial symbionts remain enigmatic. The genomes of two symbiont species have qualities common to vertically transmitted, host-dependent bacteria. However, a number of traits suggest that these symbionts may be environmentally acquired. To determine how anglerfish symbionts are transmitted, we analyzed bacteria-host codivergence across six diverse anglerfish genera. Most of the anglerfish species surveyed shared a common species of symbiont. Only one other symbiont species was found, which had a specific relationship with one anglerfish species, Cryptopsaras couesii. Host and symbiont phylogenies lacked congruence, and there was no statistical support for codivergence broadly. We also recovered symbiont-specific gene sequences from water collected near hosts, suggesting environmental persistence of symbionts. Based on these results we conclude that diverse anglerfishes share symbionts that are acquired from the environment, and that these bacteria have undergone extreme genome reduction although they are not vertically transmitted. The deep sea is home to many different species of anglerfish, a group of animals in which females often display a dangling lure on the top of their heads. This organ shelters bacteria that make light, a partnership (known as symbiosis) that benefits both parties. The bacteria get a safe environment in which to grow, while the animal may use the light to confuse predators as well as attract prey and mates. The genetic information of these bacteria has changed since they became associated with their host. Their genomes have become smaller and more specialized, limiting their ability to survive outside of the fish. This phenomenon is also observed in other symbiotic bacteria, but mostly in microorganisms that are directly transmitted from parent to offspring, never having to live on their own. Yet, some evidence suggests that the bacteria in the lure of anglerfish may be spending time in the water until they find a new host, crossing thousands of meters of ocean in the process. To explore this paradox, Baker et al. looked into the type of bacteria carried by different groups of anglerfish. If each type of fish has its own kind of bacteria, this would suggest that the microorganisms are passed from one generation to the next, and are evolving with their hosts. On the other hand, if the same sort of bacteria can be found in different anglerfish species, this would imply that the bacteria pass from host to host and evolve independently from the fish. Genetic data analysis showed that amongst six groups of anglerfishes, one species of bacteria is shared across five groups while another is specific to one type of fish. The analyses also revealed that anglerfish and their bacteria are most likely not evolving together. This means that the bacteria must make the difficult journey from host to host by persisting in the deep sea, which was confirmed by finding the genetic information of these bacteria in the water near the fish. Anglerfish and the bacteria that light up their lure are hard to study, as they live so deep in the ocean. In fact, many symbiotic relationships are equally difficult to investigate. Examining genetic information can help to give an insight into how hosts and bacteria interact across the tree of life.
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Affiliation(s)
- Lydia J Baker
- Department of Microbiology, Cornell University, New York, United States
| | - Lindsay L Freed
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, United States
| | - Cole G Easson
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, United States.,Department of Biology, Middle Tennessee State University, Murfreesboro, United States
| | - Jose V Lopez
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, United States
| | - Danté Fenolio
- Center for Conservation and Research, San Antonio Zoo, San Antonio, United States
| | - Tracey T Sutton
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Fort Lauderdale, United States
| | - Spencer V Nyholm
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, United States
| | - Tory A Hendry
- Department of Microbiology, Cornell University, New York, United States
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Ongoing Transposon-Mediated Genome Reduction in the Luminous Bacterial Symbionts of Deep-Sea Ceratioid Anglerfishes. mBio 2018; 9:mBio.01033-18. [PMID: 29946051 PMCID: PMC6020299 DOI: 10.1128/mbio.01033-18] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diverse marine fish and squid form symbiotic associations with extracellular bioluminescent bacteria. These symbionts are typically free-living bacteria with large genomes, but one known lineage of symbionts has undergone genomic reduction and evolution of host dependence. It is not known why distinct evolutionary trajectories have occurred among different luminous symbionts, and not all known lineages previously had genome sequences available. In order to better understand patterns of evolution across diverse bioluminescent symbionts, we de novo sequenced the genomes of bacteria from a poorly studied interaction, the extracellular symbionts from the "lures" of deep-sea ceratioid anglerfishes. Deep-sea anglerfish symbiont genomes are reduced in size by about 50% compared to free-living relatives. They show a striking convergence of genome reduction and loss of metabolic capabilities with a distinct lineage of obligately host-dependent luminous symbionts. These losses include reductions in amino acid synthesis pathways and abilities to utilize diverse sugars. However, the symbiont genomes have retained a number of categories of genes predicted to be useful only outside the host, such as those involved in chemotaxis and motility, suggesting that they may persist in the environment. These genomes contain very high numbers of pseudogenes and show massive expansions of transposable elements, with transposases accounting for 28 and 31% of coding sequences in the symbiont genomes. Transposon expansions appear to have occurred at different times in each symbiont lineage, indicating either independent evolutions of reduction or symbiont replacement. These results suggest ongoing genomic reduction in extracellular luminous symbionts that is facilitated by transposon proliferations.IMPORTANCE Many female deep-sea anglerfishes possess a "lure" containing luminous bacterial symbionts. Here we show that unlike most luminous symbionts, these bacteria are undergoing an evolutionary transition toward small genomes with limited metabolic capabilities. Comparative analyses of the symbiont genomes indicate that this transition is ongoing and facilitated by transposon expansions. This transition may have occurred independently in different symbiont lineages, although it is unclear why. Genomic reduction is common in bacteria that only live within host cells but less common in bacteria that, like anglerfish symbionts, live outside host cells. Since multiple evolutions of genomic reduction have occurred convergently in luminous bacteria, they make a useful system with which to understand patterns of genome evolution in extracellular symbionts. This work demonstrates that ecological factors other than an intracellular lifestyle can lead to dramatic gene loss and evolutionary changes and that transposon expansions may play important roles in this process.
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Hendry TA, de Wet JR, Dougan KE, Dunlap PV. Genome Evolution in the Obligate but Environmentally Active Luminous Symbionts of Flashlight Fish. Genome Biol Evol 2016; 8:2203-13. [PMID: 27389687 PMCID: PMC4987116 DOI: 10.1093/gbe/evw161] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2016] [Indexed: 12/17/2022] Open
Abstract
The luminous bacterial symbionts of anomalopid flashlight fish are thought to be obligately dependent on their hosts for growth and share several aspects of genome evolution with unrelated obligate symbionts, including genome reduction. However, in contrast to most obligate bacteria, anomalopid symbionts have an active environmental phase that may be important for symbiont transmission. Here we investigated patterns of evolution between anomalopid symbionts compared with patterns in free-living relatives and unrelated obligate symbionts to determine if trends common to obligate symbionts are also found in anomalopid symbionts. Two symbionts, "Candidatus Photodesmus katoptron" and "Candidatus Photodesmus blepharus," have genomes that are highly similar in gene content and order, suggesting genome stasis similar to ancient obligate symbionts present in insect lineages. This genome stasis exists in spite of the symbiont's inferred ability to recombine, which is frequently lacking in obligate symbionts with stable genomes. Additionally, we used genome comparisons and tests of selection to infer which genes may be particularly important for the symbiont's ecology compared with relatives. In keeping with obligate dependence, substitution patterns suggest that most symbiont genes are experiencing relaxed purifying selection compared with relatives. However, genes involved in motility and carbon storage, which are likely to be used outside the host, appear to be under increased purifying selection. Two chemoreceptor chemotaxis genes are retained by both species and show high conservation with amino acid sensing genes, suggesting that the bacteria may actively seek out hosts using chemotaxis toward amino acids, which the symbionts are not able to synthesize.
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Affiliation(s)
- Tory A Hendry
- Department of Ecology and Evolutionary Biology, University of Michigan Department of Microbiology, Cornell University
| | - Jeffrey R de Wet
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School
| | - Katherine E Dougan
- Department of Ecology and Evolutionary Biology, University of Michigan Present address: Department of Biological Sciences, Florida International University, Miami, FL
| | - Paul V Dunlap
- Department of Ecology and Evolutionary Biology, University of Michigan
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Jousselin E, Clamens AL, Galan M, Bernard M, Maman S, Gschloessl B, Duport G, Meseguer AS, Calevro F, Coeur d'acier A. Assessment of a 16S rRNA amplicon Illumina sequencing procedure for studying the microbiome of a symbiont-rich aphid genus. Mol Ecol Resour 2015; 16:628-40. [PMID: 26458227 DOI: 10.1111/1755-0998.12478] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 10/02/2015] [Accepted: 10/06/2015] [Indexed: 02/07/2023]
Abstract
The bacterial communities inhabiting arthropods are generally dominated by a few endosymbionts that play an important role in the ecology of their hosts. Rather than comparing bacterial species richness across samples, ecological studies on arthropod endosymbionts often seek to identify the main bacterial strains associated with each specimen studied. The filtering out of contaminants from the results and the accurate taxonomic assignment of sequences are therefore crucial in arthropod microbiome studies. We aimed here to validate an Illumina 16S rRNA gene sequencing protocol and analytical pipeline for investigating endosymbiotic bacteria associated with aphids. Using replicate DNA samples from 12 species (Aphididae: Lachninae, Cinara) and several controls, we removed individual sequences not meeting a minimum threshold number of reads in each sample and carried out taxonomic assignment for the remaining sequences. With this approach, we show that (i) contaminants accounted for a negligible proportion of the bacteria identified in our samples; (ii) the taxonomic composition of our samples and the relative abundance of reads assigned to a taxon were very similar across PCR and DNA replicates for each aphid sample; in particular, bacterial DNA concentration had no impact on the results. Furthermore, by analysing the distribution of unique sequences across samples rather than aggregating them into operational taxonomic units (OTUs), we gained insight into the specificity of endosymbionts for their hosts. Our results confirm that Serratia symbiotica is often present in Cinara species, in addition to the primary symbiont, Buchnera aphidicola. Furthermore, our findings reveal new symbiotic associations with Erwinia- and Sodalis-related bacteria. We conclude with suggestions for generating and analysing 16S rRNA gene sequences for arthropod-endosymbiont studies.
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Affiliation(s)
- E Jousselin
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
| | - A-L Clamens
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
| | - M Galan
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
| | - M Bernard
- INRA - UMR 1313 GABI-SIGENAE, INRA de Jouy en Josas, Domaine de Vilvert, 78352, Jouy en Josas, France
| | - S Maman
- INRA, GenPhySE, Sigenae, Chemin de Borde rouge -CS 52627, 31326, Castanet Tolosan, France
| | - B Gschloessl
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
| | - G Duport
- UMR 203 BF2I, Biologie Fonctionnelle Insectes et Interactions, INRA, INSA de Lyon, Université de Lyon, 20 Avenue Einstein, F-69621, Villeurbanne, France
| | - A S Meseguer
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
| | - F Calevro
- UMR 203 BF2I, Biologie Fonctionnelle Insectes et Interactions, INRA, INSA de Lyon, Université de Lyon, 20 Avenue Einstein, F-69621, Villeurbanne, France
| | - A Coeur d'acier
- INRA - UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 avenue du Campus Agropolis CS 30016, F-34 988, Montferrier-sur-Lez, France
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Dunlap P. Biochemistry and Genetics of Bacterial Bioluminescence. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2014; 144:37-64. [DOI: 10.1007/978-3-662-43385-0_2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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