With the advent of genomic sequencing and genetic analysis in the 1990s, our understanding of the relationships between different microorganisms fundamentally changed. In light of this new knowledge, what exactly is the definition of a microbial species, and how should microbiologists be categorizing microorganisms? These questions are the focus of a new report released by the American Academy of Microbiology (AAM) entitled Reconciling Microbial Systematics and Genomics.
"It is clear that the current system for designating microbial species is somewhat functional, but inadequate in many ways. It is unclear whether this system should be replaced or renovated," says Richard Roberts of New England Biolabs, one of the authors of the report.
The report is the result of a colloquium convened by the AAM in September 2006. Participants with expertise in microbial taxonomy, systematics, ecology, physiology and other areas described the history of microbial taxonomy, the state of the field today, and how work in the field should proceed in the future. The report is a record of their comments and recommendations.
In the late 1800s, in order to make sense of the vast diversity of microbiological organisms, microbial taxonomists developed a system of placing microorganisms into categories in which each organism was granted a "genus" and "species" designation. At the time, physical (or phenotypic) properties were the only means of describing microorganisms, so the system was based on measurable and observable characteristics of the organisms, not genetic traits.
In the late 20th century, molecular biology uncovered the genetic relationships between microorganisms, and some of the secrets of microbes that had yet to be cultured in the lab (and hence phenotypically characterized) were revealed.
"Much of this new knowledge was incorporated into species descriptions, but difficulties in classification persisted and novel issues arose," says Roberts. "Conflicts exist between phenotypic and phylogenetic information, the means for classifying non-cultured microbes are limited under the current paradigm, and microbial species do not always demonstrate the phenotypic or genetic cohesiveness expected of them. For these reasons and others it has become clear that the species classification framework in use today is not capable of fully portraying and organizing microbial diversity."
The report contains an in-depth review of the myriad issues and conflicts involved in the classification of microbes in the post-genomic era, including a discussion on the definition of the term "species." It ends with a set of specific recommendations including, but not limited to:
- The establishment of a subcommittee within the International Committee on Systematics of Prokaryotes to consider a paradigm shift in the species definition.
- The need for more thorough study of the mechanisms of speciation before a more meaningful and practical species theory can be developed.
- The need for more comprehensive and systematic data to uncover whether microorganisms are organized into robust, definable, biologically meaningful clusters that adhere to the concept of species.
- The acquisition of draft-quality genome sequences for all type strains to help advance the integration of genomic information into our understanding of microbial diversity and enable researchers to map phenotypes to genomes.
Jim Sliwa | EurekAlert!
Velcro for human cells
16.01.2019 | Albert-Ludwigs-Universität Freiburg im Breisgau
More efficient solar cells imitate photosynthesis
16.01.2019 | Friedrich-Alexander-Universität Erlangen-Nürnberg
Dead and alive at the same time? Researchers at the Max Planck Institute of Quantum Optics have implemented Erwin Schrödinger’s paradoxical gedanken experiment employing an entangled atom-light state.
In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. The crucial element of this gedanken...
Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.
It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:
The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.
One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...
Just in time for Christmas, a Mars-analogue mission in Morocco, coordinated by the Robotics Innovation Center of the German Research Center for Artificial Intelligence (DFKI) as part of the SRC project FACILITATORS, has been successfully completed. SRC, the Strategic Research Cluster on Space Robotics Technologies, is a program of the European Union to support research and development in space technologies. From mid-November to mid-December 2018, a team of more than 30 scientists from 11 countries tested technologies for future exploration of Mars and Moon in the desert of the Maghreb state.
Close to the border with Algeria, the Erfoud region in Morocco – known to tourists for its impressive sand dunes – offered ideal conditions for the four-week...
Research opens doors in photonic quantum information processing, optical signal processing and microwave photonics
Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new integrated photonics platform that can...
16.01.2019 | Event News
14.01.2019 | Event News
12.12.2018 | Event News
16.01.2019 | Life Sciences
16.01.2019 | Physics and Astronomy
16.01.2019 | Earth Sciences