Uncultivated Microorganisms

In 1898, an Austrian microbiologist Heinrich Winterberg made a curious observation: the number of microbial cells in his samples did not match the number of colonies formed on nutrient media (Winterberg 1898). About a decade later, J. Amann qu- tified this mismatch, which turned out to be surprisingly large, with non-growing cells outnumbering the cultivable ones almost 150 times (Amann 1911). These papers signify some of the earliest steps towards the discovery of an important phenomenon known today as the Great Plate Count Anomaly (Staley and Konopka 1985). Note how early in the history of microbiology these steps were taken. Detecting the Anomaly almost certainly required the Plate. If so, then the period from 1881 to 1887, the years when Robert Koch and Petri introduced their key inventions (Koch 1881; Petri 1887), sets the earliest boundary for the discovery, which is remarkably close to the 1898 observations by H. Winterberg. Celebrating its 111th anniversary, the Great Plate Count Anomaly today is arguably the oldest unresolved microbiological phenomenon. In the years to follow, the Anomaly was repeatedly confirmed by all microb- logists who cared to compare the cell count in the inoculum to the colony count in the Petri dish (cf., Cholodny 1929; Butkevich 1932; Butkevich and Butkevich 1936). By mid-century, the remarkable difference between the two counts became a universally recognized phenomenon, acknowledged by several classics of the time (Waksman and Hotchkiss 1937; ZoBell 1946; Jannasch and Jones 1959).

Providing a comprehensive overview and discussing developments in the field, this book details various innovative methods used in microbial ecology and environmental microbiology. It also includes all aspects of microbial diversity from bacteria and fungi to protists.

In 1898, an Austrian microbiologist Heinrich Winterberg made a curious observation: the number of microbial cells in his samples did not match the number of colonies formed on nutrient media (Winterberg 1898). About a decade later, J. Amann qu- tified this mismatch, which turned out to be surprisingly large, with non-growing cells outnumbering the cultivable ones almost 150 times (Amann 1911). These papers signify some of the earliest steps towards the discovery of an important phenomenon known today as the Great Plate Count Anomaly (Staley and Konopka 1985). Note how early in the history of microbiology these steps were taken. Detecting the Anomaly almost certainly required the Plate. If so, then the period from 1881 to 1887, the years when Robert Koch and Petri introduced their key inventions (Koch 1881; Petri 1887), sets the earliest boundary for the discovery, which is remarkably close to the 1898 observations by H. Winterberg. Celebrating its 111th anniversary, the Great Plate Count Anomaly today is arguably the oldest unresolved microbiological phenomenon. In the years to follow, the Anomaly was repeatedly confirmed by all microb- logists who cared to compare the cell count in the inoculum to the colony count in the Petri dish (cf., Cholodny 1929; Butkevich 1932; Butkevich and Butkevich 1936). By mid-century, the remarkable difference between the two counts became a universally recognized phenomenon, acknowledged by several classics of the time (Waksman and Hotchkiss 1937; ZoBell 1946; Jannasch and Jones 1959).

Endodontic Microbiology is a major new work on the microbiology and clinical treatment of endodontic pathosis. Composed of contributions from the leading educators and researchers in the field, this authoritative text offers contemporary evidence and scholarship, bringing the science of endodontic microbiology to clinical practice. Endodontic Microbiology emphasizes the importance of the biological sciences to understanding endodontic disease and its effective management. The book thoroughly examines the expanding and evolving body of knowledge about endodontic microbiology. The topics covered include persistent and resistant microorganisms, virulence factors, and systemic dissemination of endodontic microorganisms. Written by preeminent experts, Endodontic Microbiology summarizes contemporary thought in the field.

Gases with a mixing ratio of less than one percent in the lower atmosphere (i.e. the troposphere) are considered as trace gases. Numerous of these trace gases originate from biological processes in marine and terrestrial ecosystems. These gases are of relevance for the climate as they contribute to global warming or to the troposphere’s chemical reactive system that builds the ozone layer or they impact on the stability of aerosols, greenhouse, and pollutant gases. These reactive trace gases include methane, a multitude of volatile organic compounds of biogenic origin (bVOCs) and inorganic gases such as nitrogen oxides or ozone. The regulatory function of microorganisms for trace gas cycling has been intensively studied for the greenhouse gases nitrous oxide and methane, but is less well understood for microorganisms that metabolize molecular hydrogen, carbon monoxide, or bVOCs. The studies compiled this Research Topic reflect this very well. While a number of articles focus on nitrous oxide and methane or carbon monoxide oxidation, only a few articles address conversion processes of further bVOCs. The Research Topic is complemented by three review articles about the consumption of methane and monoterpenes, as well as the role of the phyllosphere as a particular habitat for trace gas-consuming microorganisms, and point out future research directions in the field. The presented scientific work illustrates that the field of microbial regulation of trace glas fluxes is still in its infancy when one broadens the view on gases beyond methane and nitrous oxide. However, there is a societal need to better predict global dynamics of trace gases that impact on the functionality and warming of the troposphere. Upcoming modelling approaches will need further information on process rates, features and distribution of the driving microorganisms to fullfill this demanding task.

This is the first work to focus on microbes in gut systems of soil animals. Beginning with an overview of the biology of soil invertebrates, the text turns to the gut microbiota of termites, which are important soil processors in tropical and subtropical regions. Coverage extends to intestinal microbiota of such other litter decomposers as earthworms, springtails, millipedes, and woodlice. Thoroughly illustrated, including color photographs.

How small can a free-living organism be? On the surface, this question is straightforward-in principle, the smallest cells can be identified and measured. But understanding what factors determine this lower limit, and addressing the host of other questions that follow on from this knowledge, require a fundamental understanding of the chemistry and ecology of cellular life. The recent report of evidence for life in a martian meteorite and the prospect of searching for biological signatures in intelligently chosen samples from Mars and elsewhere bring a new immediacy to such questions. How do we recognize the morphological or chemical remnants of life in rocks deposited 4 billion years ago on another planet? Are the empirical limits on cell size identified by observation on Earth applicable to life wherever it may occur, or is minimum size a function of the particular chemistry of an individual planetary surface? These questions formed the focus of a workshop on the size limits of very small organisms, organized by the Steering .Group for the Workshop on Size Limits of Very Small Microorganisms and held on October 22 and 23, 1998. Eighteen invited panelists, representing fields ranging from cell biology and molecular genetics to paleontology and mineralogy, joined with an almost equal number of other participants in a wide-ranging exploration of minimum cell size and the challenge of interpreting micro- and nano-scale features of sedimentary rocks found on Earth or elsewhere in the solar system. This document contains the proceedings of that workshop. It includes position papers presented by the individual panelists, arranged by panel, along with a summary, for each of the four sessions, of extensive roundtable discussions that involved the panelists as well as other workshop participants.

Advances in Microbial Ecology was established by the International Committee on Microbial Ecology (ICOME) to provide a vehicle for in-depth, critical, and even provocative reviews to emphasize recent trends in the important field of microbial ecology. Advances in Microbial Ecology is now recognized as a major source of infor mation and inspiration both for practicing and for prospective microbial ecologists. Most reviews appearing in Advances have been prepared by leaders in particular areas follow ing invitations issued by the Editorial Board. Individuals are encouraged, however, to submit outlines of unsolicited contributions to any member of the Editorial Board for consideration for publication in Advances. With the publication of Volume 12 of Advances in Microbial Ecology there will be a change of Editor and the entire Editorial Board. The current Editor wishes to take this opportunity to thank the present Editorial Board, Ron Atlas, Bo Barker J~rgensen, and Gwyn Jones, as well as past members of the Board, for their assistance and encourage ment over the years. The new Editor of Advances in Microbial Ecology will be Gwyn Jones, with Bernhard Schink, Warwick F. Vincent, and David M. Ward as members of the Editorial Board. The outgoing Board wish the new Board every success in continu ing the traditions established by Martin Alexander, the founding Editor of Advances in Microbial Ecology. The topics featured in Volume 12 of Advances include some related to the meta bolic activities of bacteria; namely, bioremediation of oil spills, by R. M. Atlas and R.