MINERALS, MATS, PEARLS AND VEILS: A PANOPLY OF GIANT SULFUR BACTERIA

The biogeochemical cycling of sulfur has been at the heart of microbial ecology since the mid-19th century. This is due, at least in part, to the striking forms of many of the organisms involved in the transformation of reduced sulfur species. Giant sulfur bacteria were among the earliest micro-organisms to capture the interest of microbiologists exploring the links between geochemical cycling of the elements and the microbiota responsible. Consequently, giant sulfur bacteria were among the first bacteria described. Organisms resembling Beggiatoa (‘ Oscillatoria alba’) were described as early as 1803 (Vaucher, 1803), but were included in the genus Beggiatoa some time later (Trevisan, 1842). Thiothrix (Rabenhorst, 1865; Winogradsky, 1888), Achromatium (Schewiakoff, 1893) and Thioploca (Lauterborn, 1907) were all described by the early 20th century and Winogradsky (1887, 1888) had already formulated the principles of lithotrophic growth based on sulfide oxidation, from his work on Beggiatoa species. Surprisingly for such conspicuous organisms, novel giant sulfur bacteria are still being described (Guerrero et al., 1999; Schulz et al., 1999).

Achromatium

Bacteria of the genus Achromatium are remarkable. Cells of up to 125 μm in length have been reported (Babenzien et al., 2005; Head et al., 2000a) and, in addition to characteristic sulfur globules that become visible on treatment of the cells with dilute acid, their large oval cells are typically filled with enormous inclusions of calcium carbonate (Fig. 1).

This volume focuses specifically upon the literature of German Expressionism, rather than the arts of painting, sculpture, music, or even architecture. Especially in the United States, the term German Expressionism first calls to mind those arts, rather than the literature of the period, and that circumstance reflects in a very positive manner the increased general familiarity with the German contribution to artistic modernism in the early twentieth century. This volume relies to some degree, necessarily, upon that familiarity, while trying to underscore the interconnectedness of the arts in this period, their shared intellectual debts and sources, and their shared general aesthetics, as suggested by the introduction. Though that very interconnectedness calls into question the notion of genre, as the one borrows from or emulates the other, genre still remains a useful organizing principle for tracking and understanding that interrelatedness. This volume thus traces a trajectory from the philosophy of Friedrich Nietzsche in its influence upon the Expressionist generation, and as literature itself; through the principal literary genres (in a less common sequence of prose, poetry, and drama), to an interdisciplinary section that first addresses the gender politics of Expressionism, and then the visual genre (of film) that most visibly absorbed the narrative impulses, visual imaginary and experimental spirit from the literature of German Expressionism. The sequence of the essays, arcing from philosophy to film, through the literary genres, would like to suggest both the centrality of the literature — the verbal artifacts related to Expressionism in this period — as well as the constant and necessary dialogue of each art with its others in this period, indeed the migration of elements of each art into the other, either under the Wagnerian rubric of Gesamtkunstwerk (total work of art) or more recently, of intermediality.

Throughout the volume, the term Expressionism has been capitalized to indicate the specific historical phenomenon of that “movement” between the years 1905 and 1925, as opposed to any sort of general expressionistic (lower case) tendency in the arts before or after that period.

The movie poster illustrations for Caligari (design Ledl Bernhard) and Genuine (design Josef Fenneker) appear in this volume courtesy of Deutsche Kinemathek Berlin.

For their generous permission to reprint Edvard Munch's portrait of Friedrich Nietzsche (1906) I would like to thank the Thielska-Galleriet in Stockholm, Sweden, and Karin Meddings in particular.

SUMMARY

1. Molecular biological methods have provided new insights into the true extent of bacterial diversity in soil, and here we focus on their application in tandem with soil process measurements.

2. Data from a field experiment are used to illustrate the impact of perturbation on the total bacterial community as well as those functional groups responsible for nitrification, denitrification, methanogenesis and methane oxidation. Increasing the organic matter by about 20% by sewage sludge addition had no statistically significant effect on soil respiration rates, and although methanogenesis and methane oxidation were both stimulated, the effect was short lived and variable. We argue that the methane transformations are particularly dependent on unevenly distributed microsite activity, unlike nitrification/denitrification rates, which were stimulated by liming and organic matter addition in a manner that was both reproducible and persistent. The genetic diversity of the ammonia-oxidising bacteria concomitantly decreased, implying classical selection or enrichment of competitive species upon perturbation.

3. Effects on the diversity of the soil bacterial flora quickly disappeared with time, and we argue that seasonal variation, and particularly its effect on plant growth, has a greater impact on the dynamics of bacterial populations in soil than single time-point perturbations aimed at stimulating general biological activity. However, time course experiments revealed that the bacterial diversity in untreated soils was more stable, as the 16S rRNA gene profiles were more stable than those that developed in disturbed soils.

4. […]