Learning from microorganisms: using new insights in microbial physiology for sustainable nitrogen management.

Diverse nitrogen-transforming microorganisms with a wide variety of physiological properties are employed for biological nitrogen removal from wastewater. There are many technologies that achieve the required nitrogen discharge standards; however, greenhouse gas emissions and energy consumption constitute the bulk of the environmental footprint of wastewater treatment plants. In this review, we highlight current and proposed approaches aiming to achieve more energy-efficient and environment-friendly biological nitrogen removal, discuss whether new discoveries in microbial physiology of nitrogen-transforming microorganisms could be used to reduce greenhouse gas emissions, and summarize recent advances in ammonium recovery from wastewater.

Improved enrichment culture technique for methane-oxidizing bacteria from marine ecosystems: the effect of adhesion material and gas composition.

Cultivation of microbial representatives of specific functional guilds from environmental samples depends largely on the suitability of the applied growth conditions. Especially the cultivation of marine methanotrophs has received little attention, resulting in only a limited number of ex situ cultures available. In this study we investigated the effect of adhesion material and headspace composition on the methane oxidation activity in methanotrophic enrichments obtained from marine sediment.

New Methyloceanibacter diversity from North Sea sediments includes methanotroph containing solely the soluble methane monooxygenase.

Marine methylotrophs play a key role in the global carbon cycle by metabolizing reduced one-carbon compounds that are found in high concentrations in marine environments. Genome, physiology and diversity studies have been greatly facilitated by the numerous model organisms brought into culture. However, the availability of marine representatives remains poor.

Draft Genome Sequences of Eight Obligate Methane Oxidizers Occupying Distinct Niches Based on Their Nitrogen Metabolism.

The genome sequences of Methylomonas methanica (NCIMB 11130(T), R-45363, and R-45371), Methylomonas koyamae (R-45378, R-45383, and R-49807), Methylomonas lenta (R-45370), and Methylosinus sp. (R-45379) were obtained. These aerobic methanotrophs were isolated from terrestrial ecosystems, and their distinct phenotypes related to nitrogen assimilation and dissimilation were previously reported.

Genome Characteristics of Two Novel Type I Methanotrophs Enriched from North Sea Sediments Containing Exclusively a Lanthanide-Dependent XoxF5-Type Methanol Dehydrogenase.

Microbial methane oxidizers play a crucial role in the oxidation of methane in marine ecosystems, as such preventing the escape of excessive methane to the atmosphere. Despite the important role of methanotrophs in marine ecosystems, only a limited number of isolates are described, with only four genomes available. Here, we report on two genomes of gammaproteobacterial methanotroph cultures, affiliated with the deep-sea cluster 2, obtained from North Sea sediment.

A generally applicable cryopreservation method for nitrite-oxidizing bacteria.

Nitrite-oxidizing bacteria are key members of the global nitrogen cycle but their study is hampered by their limited availability in culture, mostly due to laborious cultivation procedures and the lack of stable preservation methods. In this study, it was demonstrated that long-term cryopreservation of nitrite-oxidizing bacteria assigned to the genera Nitrobacter, Nitrospina, Nitrococcus, Nitrotoga and Nitrospira was possible using a simple and rapid protocol. Their survival was tested with different cryoprotecting agents, DMSO and Hatefi, and in various carbon-rich preservation media, ten-fold diluted TSB, and ten-fold diluted TSB supplemented with 1% trehalose, and 1% sucrose.

Safeguarding bacterial resources promotes biotechnological innovation.

Environmental research delivers valuable bacterial resources for biotechnology. We believe that systematic long-term preservation of bacteria will promote future biotechnological innovations, by safeguarding the accessibility of bacteria already recognized to have interesting features and providing a "pool" of bacterial resources for novel applied research. To this end, we want to advocate the incorporation of preservation tests in environmental or applied microbiological research.