Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Birgit Gemeinholzer is active.

Publication


Featured researches published by Birgit Gemeinholzer.


Biopreservation and Biobanking | 2011

The DNA Bank Network: The Start from a German Initiative

Birgit Gemeinholzer; Gabriele Dröge; Holger Zetzsche; Gerhard Haszprunar; Hans-Peter Klenk; Anton Güntsch; Walter G. Berendsohn; Johann-Wolfgang Wägele

The explicit aim of the DNA Bank Network is to close the divide between biological specimen collections and molecular sequence databases. It provides a technically optimized DNA and tissue collection service facility in the interest of all biological research, with access to well-documented DNA-containing samples and voucher specimens as well as to corresponding molecular data stored in public sequence databases. The Network enables scientists to (i) query and order DNA samples of organisms collected from natural habitats via a shared Web portal, (ii) store DNA samples for reference under optimal conditions after project completion or data publication, (iii) obtain DNA material to conduct new studies or to extend and complement previous investigations, and (iv) support good scientific practice as the deposition of DNA samples and related specimens facilitates the verification of published results.


Molecular Ecology Resources | 2015

Metabarcoding vs. morphological identification to assess diatom diversity in environmental studies

Jonas Zimmermann; Gernot Glöckner; Regine Jahn; Neela Enke; Birgit Gemeinholzer

Diatoms are frequently used for water quality assessments; however, identification to species level is difficult, time‐consuming and needs in‐depth knowledge of the organisms under investigation, as nonhomoplastic species‐specific morphological characters are scarce. We here investigate how identification methods based on DNA (metabarcoding using NGS platforms) perform in comparison to morphological diatom identification and propose a workflow to optimize diatom fresh water quality assessments. Diatom diversity at seven different sites along the course of the river system Odra and Lusatian Neisse from the source to the mouth is analysed with DNA and morphological methods, which are compared. The NGS technology almost always leads to a higher number of identified taxa (270 via NGS vs. 103 by light microscopy LM), whose presence could subsequently be verified by LM. The sequence‐based approach allows for a much more graduated insight into the taxonomic diversity of the environmental samples. Taxa retrieval varies considerably throughout the river system, depending on species occurrences and the taxonomic depth of the reference databases. Mostly rare taxa from oligotrophic parts of the river systems are less well represented in the reference database used. A workflow for DNA‐based NGS diatom identification is presented. 28 000 diatom sequences were evaluated. Our findings provide evidence that metabarcoding of diatoms via NGS sequencing of the V4 region (18S) has a great potential for water quality assessments and could complement and maybe even improve the identification via light microscopy.


Nucleic Acids Research | 2014

The Global Genome Biodiversity Network (GGBN) Data Portal

Gabriele Droege; Katharine Barker; Jonas J. Astrin; Paul Bartels; Carol Butler; David Cantrill; Jonathan A. Coddington; Fé Forest; Birgit Gemeinholzer; Donald Hobern; Jacqueline Mackenzie-Dodds; Éamonn Ó Tuama; Gitte Petersen; Oris I. Sanjur; David E. Schindel; Ole Seberg

The Global Genome Biodiversity Network (GGBN) was formed in 2011 with the principal aim of making high-quality well-documented and vouchered collections that store DNA or tissue samples of biodiversity, discoverable for research through a networked community of biodiversity repositories. This is achieved through the GGBN Data Portal (http://data.ggbn.org), which links globally distributed databases and bridges the gap between biodiversity repositories, sequence databases and research results. Advances in DNA extraction techniques combined with next-generation sequencing technologies provide new tools for genome sequencing. Many ambitious genome sequencing projects with the potential to revolutionize biodiversity research consider access to adequate samples to be a major bottleneck in their workflow. This is linked not only to accelerating biodiversity loss and demands to improve conservation efforts but also to a lack of standardized methods for providing access to genomic samples. Biodiversity biobank-holding institutions urgently need to set a standard of collaboration towards excellence in collections stewardship, information access and sharing and responsible and ethical use of such collections. GGBN meets these needs by enabling and supporting accessibility and the efficient coordinated expansion of biodiversity biobanks worldwide.


Plant Biology | 2011

Genetic population structure, fitness variation and the importance of population history in remnant populations of the endangered plant Silene chlorantha (Willd.) Ehrh. (Caryophyllaceae)

Daniel Lauterbach; Michael Ristow; Birgit Gemeinholzer

Habitat fragmentation can lead to a decline of genetic diversity, a potential risk for the survival of natural populations. Fragmented populations can become highly differentiated due to reduced gene flow and genetic drift. A decline in number of individuals can result in lower reproductive fitness due to inbreeding effects. We investigated genetic variation within and between 11 populations of the rare and endangered plant Silene chlorantha in northeastern Germany to support conservation strategies. Genetic diversity was evaluated using AFLP techniques and the results were correlated to fitness traits. Fitness evaluation in nature and in a common garden approach was conducted. Our analysis revealed population differentiation was high and within population genetic diversity was intermediate. A clear population structure was supported by a Bayesian approach, AMOVA and neighbour-joining analysis. No correlation between genetic and geographic distance was found. Our results indicate that patterns of population differentiation were mainly caused by temporal and/or spatial isolation and genetic drift. The fitness evaluation revealed that pollinator limitation and habitat quality seem, at present, to be more important to reproductive fitness than genetic diversity by itself. Populations of S. chlorantha with low genetic diversity have the potential to increase in individual number if habitat conditions improve. This was detected in a single large population in the investigation area, which was formerly affected by bottleneck effects.


Organisms Diversity & Evolution | 2013

Divergence time estimation in Cichorieae (Asteraceae) using a fossil-calibrated relaxed molecular clock

Karin Tremetsberger; Birgit Gemeinholzer; Holger Zetzsche; Stephen Blackmore; Norbert Kilian; Salvador Talavera

Knowing the age of lineages is key to understanding their biogeographic history. We aimed to provide the best estimate of the age of Cichorieae and its subtribes based on available fossil evidence and DNA sequences and to interpret their biogeography in the light of Earth history. With more than 1,550 species, the chicory tribe (Cichorieae, Asteraceae) is distributed predominantly in the northern Hemisphere, with centres of distribution in the Mediterranean region, central Asia, and SW North America. Recently, a new phylogenetic hypothesis of Cichorieae based on ITS sequences has been established, shedding new light on phylogenetic relationships within the tribe, which had not been detected so far. Cichorieae possess echinolophate pollen grains, on the surface of which cavities (lacunae) are separated by ridges. These lacunae and ridges show patterns characteristic of certain groups within Cichorieae. Among the fossil record of echinolophate pollen, the Cichorium intybus-type is the most frequent and also the oldest type (22 to 28.4 million years old). By using an uncorrelated relaxed molecular clock approach, the Cichorieae phylogenetic tree was calibrated with this fossil find. According to the analysis, the tribe originated no later than Oligocene. The species-rich core group originated no later than Late Oligocene or Early Miocene and its subtribes diversified no later than Middle/Late Miocene or Early Pliocene—an eventful period of changing geological setting and climate in the Mediterranean region and Eurasia. The first dispersal from Eurasia to North America, which resulted in the radiation of genera and species in North America (subtribe Microseridinae), also occurred no later than Middle or Late Miocene, suggesting the Bering land bridge as the route of dispersal.


Ecological Informatics | 2012

A comparative evaluation of technical solutions for long-term data repositories in integrative biodiversity research

Kerstin Bach; Daniel Schäfer; Neela Enke; Bernhard Seeger; Birgit Gemeinholzer; Jörg Bendix

Abstract The current study investigates existing infrastructure, its technical solutions and implemented standards for data repositories related to integrative biodiversity research. The storage and reuse of complex biodiversity data in central databases are becoming increasingly important, particularly in attempts to cope with the impacts of environmental change on biodiversity and ecosystems. From the data side, the main challenge of biodiversity repositories is to deal with the highly interdisciplinary and heterogeneous character of standardized and unstandardized data and metadata covering information from genes to ecosystems. Furthermore, the technical improvements in data acquisition techniques produce ever larger data volumes, which represent a challenge for database structure and proper data exchange. The current study is based on comprehensive in-depth interviews and an online survey addressing IT specialists involved in database development and operation. The results show that metadata are already well established, but that non-meta data still is largely unstandardized across various scientific communities. For example, only a third of all repositories in our investigation use internationally unified semantic standard checklists for taxonomy. The study also showed that database developers are mostly occupied with the implementation of state of the art technology and solving operational problems, leaving no time to implement users requirements. One of the main reasons for this dissatisfying situation is the undersized and unreliable funding situation of most repositories, as reflected by the marginally small number of permanent IT staff members. We conclude that a sustainable data management system that fosters the future use and reuse of these valuable data resources requires the development of fewer, but more permanent data repositories using commonly accepted standards for their long-term data. This can only be accomplished through the consolidation of hitherto widely scattered small and non-permanent repositories.


PLOS ONE | 2016

Open Data in Global Environmental Research: The Belmont Forum’s Open Data Survey

Birgit Schmidt; Birgit Gemeinholzer; Andrew E. Treloar

This paper presents the findings of the Belmont Forum’s survey on Open Data which targeted the global environmental research and data infrastructure community. It highlights users’ perceptions of the term “open data”, expectations of infrastructure functionalities, and barriers and enablers for the sharing of data. A wide range of good practice examples was pointed out by the respondents which demonstrates a substantial uptake of data sharing through e-infrastructures and a further need for enhancement and consolidation. Among all policy responses, funder policies seem to be the most important motivator. This supports the conclusion that stronger mandates will strengthen the case for data sharing.


Organisms Diversity & Evolution | 2012

Molecular and phytochemical systematics of the subtribe Hypochaeridinae (Asteraceae, Cichorieae)

Neela Enke; Birgit Gemeinholzer; Christian Zidorn

The systematics of the Hypochaeridinae subtribe was re-evaluated based on a combination of published and new molecular data. Newly found clades were additionally characterized using published and new phytochemical data. In addition to flavonoids and sesquiterpene lactones, which had been reviewed recently as chemosystematic markers in the Cichorieae, we analysed the reported occurrences of caffeic acid derivatives and their potential as chemosystematic markers. Our molecular results required further changes in the systematics of the genus Leontodon. Based on previous molecular data, Leontodon s.l.—i.e. including sections Asterothrix, Leontodon, Thrincia, Kalbfussia, and Oporinia (Widder 1975)—had been split into the genera Leontodon s.str. (sections Asterothrix, Leontodon, and Thrincia) and Scorzoneroides (sections Kalbfussia and Oporinia). Instead of splitting Leontodon into even a higher number of segregate genera we propose to include Hedypnois into Leontodon s.str. and here into section Leontodon. Moreover, sections Asterothrix and Leontodon should be merged into a single section Leontodon. The newly defined genus Leontodon is characterised by the unique occurrence of hydroxyhypocretenolides. The monophyly of the genus Hypochaeris is neither supported nor contradicted and potentially comprises two separate molecular clades. The clade Hypochaeris I comprises the majority of the European and Mediterranean as well as all South American taxa of Hypochaeris s.l. while the clade Hypochaeris II encompasses only H. achyrophorus L., H. glabra L., H. laevigata Benth. & Hook.f., and H. radicata L.


Database | 2016

The Global Genome Biodiversity Network (GGBN) Data Standard specification

Gabriele Droege; Katharine Barker; Ole Seberg; Jonathan A. Coddington; Erica E. Benson; Walter G. Berendsohn; B. Bunk; Carol Butler; E. M. Cawsey; John Deck; Markus Döring; P. Flemons; Birgit Gemeinholzer; Anton Güntsch; T. Hollowell; Patricia Kelbert; Ivaylo Kostadinov; Renzo Kottmann; Rita T. Lawlor; C. Lyal; Jacqueline Mackenzie-Dodds; Christopher P. Meyer; Daniel G. Mulcahy; Sara Y. Nussbeck; é. O'Tuama; T. Orrell; Gitte Petersen; Tim Robertson; C. Söhngen; Jamie Whitacre

Genomic samples of non-model organisms are becoming increasingly important in a broad range of studies from developmental biology, biodiversity analyses, to conservation. Genomic sample definition, description, quality, voucher information and metadata all need to be digitized and disseminated across scientific communities. This information needs to be concise and consistent in today’s ever-increasing bioinformatic era, for complementary data aggregators to easily map databases to one another. In order to facilitate exchange of information on genomic samples and their derived data, the Global Genome Biodiversity Network (GGBN) Data Standard is intended to provide a platform based on a documented agreement to promote the efficient sharing and usage of genomic sample material and associated specimen information in a consistent way. The new data standard presented here build upon existing standards commonly used within the community extending them with the capability to exchange data on tissue, environmental and DNA sample as well as sequences. The GGBN Data Standard will reveal and democratize the hidden contents of biodiversity biobanks, for the convenience of everyone in the wider biobanking community. Technical tools exist for data providers to easily map their databases to the standard. Database URL: http://terms.tdwg.org/wiki/GGBN_Data_Standard


Willdenowia | 2007

Studies in the Compositae of the Arabian Peninsula and Socotra — 7. Erythroseris, a new genus and the previously unknown sister group of Cichorium (Cichorieae subtribe Cichoriinae)

Norbert Kilian; Birgit Gemeinholzer

Abstract Kilian, N. & Gemeinholzer, B.: Studies in the Compositae of the Arabian Peninsula and Socotra — 7. Erythroseris, a new genus and the previously unknown sister group of Cichorium (Cichorieae subtribe Cichoriinae). — Willdenowia 37: 283–296. — ISSN 0511-9618;

Collaboration


Dive into the Birgit Gemeinholzer's collaboration.

Top Co-Authors

Avatar

Neela Enke

Free University of Berlin

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Holger Zetzsche

Free University of Berlin

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Norbert Kilian

Free University of Berlin

View shared research outputs
Top Co-Authors

Avatar

Regine Jahn

Free University of Berlin

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Birgit Schmidt

University of Göttingen

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Gabriele Droege

Free University of Berlin

View shared research outputs
Researchain Logo
Decentralizing Knowledge