Diversity of Microbial Mats in the Makgadikgadi Salt Pans, Botswana.

The Makgadikgadi Salt Pans are the remnants of a mega paleo-lake system in the central Kalahari, Botswana. Today, the Makgadikgadi Basin is an arid to semi-arid area receiving water of meteoric origin during the short, wet season. Large microbial mats, which support primary production, are formed due to desiccation during the dry season.

The wild-type flagellar filament of the Firmicute Kurthia at 2.8 Å resolution in vivo.

Bacteria swim and swarm by rotating the micrometers long, helical filaments of their flagella. They change direction by reversing their flagellar rotation, which switches the handedness of the filament's supercoil. So far, all studied functional filaments are composed of a mixture of L- and R-state flagellin monomers.

Adaptive Strategies in a Poly-Extreme Environment: Differentiation of Vegetative Cells in and Resistance to Extreme Conditions.

Poly-extreme terrestrial habitats are often used as analogs to extra-terrestrial environments. Understanding the adaptive strategies allowing bacteria to thrive and survive under these conditions could help in our quest for extra-terrestrial planets suitable for life and understanding how life evolved in the harsh early earth conditions. A prime example of such a survival strategy is the modification of vegetative cells into resistant resting structures.

Bacterial spores, from ecology to biotechnology.

The production of a highly specialized cell structure called a spore is a remarkable example of a survival strategy displayed by bacteria in response to challenging environmental conditions. The detailed analysis and description of the process of sporulation in selected model organisms have generated a solid background to understand the cellular processes leading to the formation of this specialized cell. However, much less is known regarding the ecology of spore-formers.

Dissemination of antibiotic resistance genes associated with the sporobiota in sediments impacted by wastewater.

Aquatic ecosystems serve as a dissemination pathway and a reservoir of both antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARG). In this study, we investigate the role of the bacterial sporobiota to act as a vector for ARG dispersal in aquatic ecosystems. The sporobiota was operationally defined as the resilient fraction of the bacterial community withstanding a harsh extraction treatment eliminating the easily lysed fraction of the total bacterial community.

A historical legacy of antibiotic utilization on bacterial seed banks in sediments.

The introduction of antibiotics for both medical and non-medical purposes has had a positive effect on human welfare and agricultural output in the past century. However, there is also an important ecological legacy regarding the use of antibiotics and the consequences of increased levels of these compounds in the environment as a consequence of their use and disposal. This legacy was investigated by quantifying two antibiotic resistance genes (ARG) conferring resistance to tetracycline ((W)) and sulfonamide (1) in bacterial seed bank DNA in sediments.

A Combination of Extreme Environmental Conditions Favor the Prevalence of Endospore-Forming Firmicutes.

Environmental conditions unsuitable for microbial growth are the rule rather than the exception in most habitats. In response to this, microorganisms have developed various strategies to withstand environmental conditions that limit active growth. Endospore-forming Firmicutes (EFF) deploy a myriad of survival strategies in order to resist adverse conditions.

Anoxybacillusgeothermalis sp. nov., a facultatively anaerobic, endospore-forming bacterium isolated from mineral deposits in a geothermal station.

A novel endospore-forming bacterium designated strain GSsed3T was isolated from deposits clogging aboveground filters from the geothermal power platform of Groß Schönebeck in northern Germany. The novel isolate was Gram-staining-positive, facultatively anaerobic, catalase-positive and oxidase-positive. Optimum growth occurred at 60 °C, 0.

Exploiting the fungal highway: development of a novel tool for the in situ isolation of bacteria migrating along fungal mycelium.

Fungi and bacteria form various associations that are central to numerous environmental processes. In the so-called fungal highway, bacteria disperse along fungal mycelium. We developed a novel tool for the in situ isolation of bacteria moving along fungal hyphae as well as for the recovery of fungi potentially involved in dispersal, both of which are attracted towards a target culture medium.

Genome Sequence of Bacillus alveayuensis Strain 24KAM51, a Halotolerant Thermophile Isolated from a Hydrothermal Vent.

Bacillus alveayuensis strain 24KAM51 was isolated from a marine hydrothermal vent in Milos, Greece. Its genome depicts interesting features of halotolerance and resistance to heavy metals.

Genome Sequence of Aeribacillus pallidus Strain GS3372, an Endospore-Forming Bacterium Isolated in a Deep Geothermal Reservoir.

The genome of strain GS3372 is the first publicly available strain of Aeribacillus pallidus. This endospore-forming thermophilic strain was isolated from a deep geothermal reservoir. The availability of this genome can contribute to the clarification of the taxonomy of the closely related Anoxybacillus, Geobacillus, and Aeribacillus genera.

Biofilm synthesis and presence of virulence factors among enterococci isolated from patients and water samples.

The goal of this study was to compare biofilm synthesis among enterococci recovered from clinical samples (infection or colonization) of patients as well as environmental samples in order to determine possible virulence factors and clonal relationship. During a two-year period, clinical samples (blood, catheter tips, bronchial secretions, wounds, peritoneal fluid, urine) and rectal swabs collected from hospitalized patients as well as environmental water samples were tested for the presence of Enterococcus faecalis and Enterococcus faecium. Antibiotic susceptibility testing was performed by the disc diffusion method and Etest.

Genome Sequence of Anoxybacillus geothermalis Strain GSsed3, a Novel Thermophilic Endospore-Forming Species.

Anoxybacillus geothermalis strain GSsed3 is an endospore-forming thermophilic bacterium isolated from filter deposits in a geothermal site. This novel species has a larger genome size (7.2 Mb) than that of any other Anoxybacillus species, and it possesses genes that support its phenotypic metabolic characterization and suggest an intriguing link to metals.

Under-detection of endospore-forming Firmicutes in metagenomic data.

Microbial diversity studies based on metagenomic sequencing have greatly enhanced our knowledge of the microbial world. However, one caveat is the fact that not all microorganisms are equally well detected, questioning the universality of this approach. Firmicutes are known to be a dominant bacterial group.

Genome Sequence of Kosakonia radicincitans Strain YD4, a Plant Growth-Promoting Rhizobacterium Isolated from Yerba Mate (Ilex paraguariensis St. Hill.).

Kosakonia radicincitans strain YD4 is a rhizospheric isolate from yerba mate (Ilex paraguariensis St. Hill.) with plant growth-promoting effects on this crop.

Gains of bacterial flagellar motility in a fungal world.

The maintenance of energetically costly flagella by bacteria in non-water-saturated media, such as soil, still presents an evolutionary conundrum. Potential explanations have focused on rare flooding events allowing dispersal. Such scenarios, however, overlook bacterial dispersal along mycelia as a possible transport mechanism in soils.

Environmental surveillance. An additional/alternative approach for virological surveillance in Greece?

The detection of viruses in the sewage of an urban city by nucleic acid amplification techniques allows the identification of the viral strains that are circulating in the community. The aim of the study was the application of such detection which gives useful data on the distribution, spread, and frequency of these viruses, supporting epidemiological studies of the related viral infections. A two year (2007-2009) survey was conducted in order to evaluate the presence of human adenoviruses (hAdV), hepatitis A viruses (HAV), hepatitis E viruses (HEV), noroviruses (NoV), and human polyomaviruses (hPyV) in sewage samples collected from the inlet of a municipal biological wastewater treatment plant located in southwestern Greece.

Molecular characterization of hepatitis A virus isolates from environmental and clinical samples in Greece.

Background: Hepatitis A virus (HAV) strains detected in environmental and clinical samples were analysed to characterize the genotypes of HAV circulating in Greece. Fifty (50) sewage samples were collected from Patras (South-Western Greece) and Alexandroupolis (North-Eastern Greece) from 2007 until 2009, accordingly. The clinical samples derived from an HAV outbreak involved populations from three neighbouring prefectures of North-Eastern Greece (Xanthi, Rodopi, and Evros).