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Terrestrial tropical methane seep habitats are important ecosystems in the methane cycle. Methane oxidizing bacteria play a key role in these ecosystems as they reduce methane emissions to the atmosphere. Here, we describe the isolation and initial characterization of two novel moderately thermophilic and acid-tolerant obligate methanotrophs, assigned BFH1 and BFH2 recovered from a tropical methane seep topsoil habitat. The new isolates were strictly aerobic, non-motile, coccus-shaped and utilized methane and methanol as sole carbon and energy source. Isolates grew at pH range 4.2-7.5 (optimal 5.5-6.0) and at a temperature range of 30-60°C (optimal 51-55°C). 16S rRNA gene phylogeny placed them in a well-separated branch forming a cluster together with the genus Methylocaldum as the closest relatives (93.1-94.1% sequence similarity). The genes pmoA, mxaF, and cbbL were detected, but mmoX was absent. Strains BFH1 and BFH2 are, to our knowledge, the first isolated acid-tolerant moderately thermophilic methane oxidizers of the class Gammaproteobacteria. Each strain probably denotes a novel species and they most likely represent a novel genus within the family Methylococcaceae of type I methanotrophs. Furthermore, the isolates increase our knowledge of acid-tolerant aerobic methanotrophs and signify a previously unrecognized biological methane sink in tropical ecosystems.

Methylococcus capsulatus (Bath) is a methanotroph that possesses both a membrane-embedded (pMMO) and a soluble methane monooxygenase (sMMO). The expression of these two MMO's is tightly controlled by the availability of copper in the growth medium, but the underlying mechanisms and the number of genes involved in this switch in methane oxidation is not yet fully elucidated. Microarray analyses were used to assess the transcriptome in cells producing either pMMO or sMMO. A total of 137 genes were differentially expressed, with 87 genes showing a significant up-regulation during sMMO production. The majority of the differentially expressed genes could be assigned to functional roles in the energy metabolism and transport. Furthermore, three copper responding gene clusters were discovered, including an extended cluster that also harbors the genes for sMMO. Our data also indicates that major changes takes place in the respiratory chain between pMMO- and sMMO-producing cells, and that quinone are predominantly used as the electron donors for methane oxidation by pMMO. Intriguingly, a large proportion of the differentially expressed genes between pMMO- and sMMO-producing cells encode c-type cytochromes. By combining microarray- and mass spectrometry data, a total of 35 c-type cytochromes are apparently expressed in M. capsulatus when grown in nitrate mineral salt medium with methane as sole energy and carbon source, and the expression of 21 of these respond to the availability of copper. Interestingly, several of these c-type cytochromes are recovered from the cell surface, suggesting that extracellular electron transfers may occur in M. capsulatus., (© 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

Subtilisins and other serine proteases are extensively used in the detergent, leather and food industry, and frequently under non-physiological conditions. New proteases with improved performance at extreme temperatures and in the presence of chemical additives may have great economical potential. The increasing availability of genetic sequences from different environments makes homology-based screening an attractive strategy for discovery of new proteases. A prerequisite for large-scale screening of protease-encoding sequences is an efficient screening procedure. We have developed and implemented a screening procedure that encompasses cloning of candidate sequences into multiple expression vectors, cytoplasmic expression in E. coli, and a casein-based functional screen. The procedure is plate-format compatible and can be completed in only four days, starting from the gene of interest in a suitable cloning vector. The expression vector suite includes six vectors with combinations of maltose-binding protein (MBP) or the small ubiquitin-related modifier (SUMO) for increased solubility, and polyhistidine tags for downstream purification. We used enhanced green fluorescent protein and four Bacilli subtilisins to validate the screening procedure and our results show that proteins were expressed, soluble and active. Interestingly, the highest activities were consistently achieved with either MBP or SUMO fusions, thus demonstrating the merit of including solubility tags. In conclusion, the results demonstrate that our approach can be used to efficiently screen for new subtilisins, and suggest that the approach may also be used to screen for proteins with other activities., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Was district medical officer Jensen the first doctor to describe patients with Pantothenate Kinase-Associated Neurodegeneration (PKAN) in Volda in 1830? A case series of four siblings with the same disease written by district medical officer Peter Jensen (1799-1832) in Aalesund in 1830, was published in the Norwegian medical journal Eyr in 1832. The children, who were healthy almost up to school age, developed dystonic involuntary movements and deformities in all extremities, lost their ability to speak and were emaciated before they died at around the age of nine years. Further information about the family and a fifth affected child has been found in the parish records. The clinical picture is consistent with Pantothenate Kinase-Associated Neurodegeneration (PKAN), a rare condition with basal ganglia iron deposition, described in 1922 by the German neuropathologists Julius Hallervorden (1882-1965) and Hugo Spatz (1888-1969). The disease was formerly called Hallervorden-Spatz syndrome, but because of the medical activities undertaken by these two researchers before and during the Second World War, this eponym is no longer recommended.

Terrestrial methane seeps and rice paddy fields are important ecosystems in the methane cycle. Methanotrophic bacteria in these ecosystems play a key role in reducing methane emission into the atmosphere. Here, we describe three novel methanotrophs, designated BRS-K6, GFS-K6 and AK-K6, which were recovered from three different habitats in contrasting geographic regions and ecosystems: waterlogged rice-field soil and methane seep pond sediments from Bangladesh; and warm spring sediments from Armenia. All isolates had a temperature range for growth of 8-35 °C (optimal 25-28 °C) and a pH range of 5.0-7.5 (optimal 6.4-7.0). 16S rRNA gene sequences showed that they were new gammaproteobacterial methanotrophs, which form a separate clade in the family Methylococcaceae. They fell into a cluster with thermotolerant and mesophilic growth tendency, comprising the genera Methylocaldum-Methylococcus-Methyloparacoccus-Methylogaea. So far, growth below 15 °C of methanotrophs from this cluster has not been reported. The strains possessed type I intracytoplasmic membranes. The genes pmoA, mxaF, cbbL, nifH were detected, but no mmoX gene was found. Each strain probably represents a novel species either belonging to the same novel genus or each may even represent separate genera. These isolates extend our knowledge of methanotrophic Gammaproteobacteria and their physiology and adaptation to different ecosystems.

Norwegian medicine is interwoven with the country's history, social structure, and its organization of health services. Health services in Norway are based on an ideology of equality and solidarity in which decentralization and strong primary care are crucial elements. The aim is treatment at the lowest effective level of care, irrespective of patients' financial or social status. Health services have high political priority and people expect a great deal of them. The medical profession in Norway has a double loyalty: to the individual patient and to society at large. The gate keeper-role, which has been most prominent among general practitioners, reflects economic responsibility as well as some hesitation in the use of extensive diagnostic and therapeutic procedures. Norwegian medicine has never been particularly eager on interventions. This could be explained both by strong governmental control and a traditional Norwegian moderation. The medical profession is less homogenous than before, but still has a strong community of communication. The concept of health among Norwegians is pragmatic and holistic. The relationship between health and nature is strong and in line with people's conception of nature in general. Social developments such as individualization, internationalization and economic ways of thinking together with increasing specialization and market adjustment in the health services make for rapid changes in Norwegian medicine. It is more and more difficult to define national features, but those existing are well worth defending.

The nation-building process in Norway took mainly place before the Norwegian-Swedish union came to a close in 1905. This was not a dramatic change, though the end of the union did bring a lift to Norwegian national consciousness. In 1905 there were three general medical journals in Norway and approximately 1200 doctors. German was the most important language of international science, but most scientific publishing was done in Norwegian. After the Second World War, English became the dominating language of scientific communication. Twentieth-century medicine and medical publishing was an era of specialisation and internationalisation. Norwegian medicine has to a large extent been internationalised through Nordic cooperation, with the Nordic specialist journals being of particular importance. With increasing professionalism in research, international English-language journals have become the major channels of communication, though several Norwegian-language journals (on paper or on the internet) have been established and are of crucial importance to a national identity within medical specialties. In 2005 there is only one general medical journal in Norwegian, in a country with approximately 20,000 doctors. A national identity related to medical publishing is not given much attention, though national medicine is still closely tied in with national culture. Good clinical practice should be based on a firm knowledge of local society and local tradition. This is a challenge in contemporary medical publishing.

For a long time, the haemerythrin family of proteins was considered to be restricted to only a few phyla of marine invertebrates. When analysing differential protein expression in the methane-oxidizing bacterium, Methylococcus capsulatus (Bath), grown at a high and low copper-to-biomass ratio, respectively, we identified a putative prokaryotic haemerythrin expressed in high-copper cultures. Haemerythrins are recognized by a conserved sequence motif that provides five histidines and two carboxylate ligands which coordinate two iron atoms. The diiron site is located in a hydrophobic pocket and is capable of binding O(2). We cloned the M. capsulatus haemerythrin gene and expressed it in Escherichia coli as a fusion protein with NusA. The haemerythrin protein was purified to homogeneity cleaved from its fusion partner. Recombinant M. capsulatus haemerythrin (McHr) was found to fold into a stable protein. Sequence similarity analysis identified all the candidate residues involved in the binding of diiron (His22, His58, Glu62, His77, His81, His117, Asp122) and the amino acids forming the hydrophobic pocket in which O(2) may bind (Ile25, Phe59, Trp113, Leu114, Ile118). We were also able to model a three-dimensional structure of McHr maintaining the correct positioning of these residues. Furthermore, UV/vis spectrophotometric analysis demonstrated the presence of conjugated diiron atoms in McHr. A comprehensive genomic database search revealed 21 different prokaryotes containing the haemerythrin signature (PROSITE 00550), indicating that these putative haemerythrins may be a conserved prokaryotic subfamily.

Methanotrophs are ubiquitous bacteria that can use the greenhouse gas methane as a sole carbon and energy source for growth, thus playing major roles in global carbon cycles, and in particular, substantially reducing emissions of biologically generated methane to the atmosphere. Despite their importance, and in contrast to organisms that play roles in other major parts of the carbon cycle such as photosynthesis, no genome-level studies have been published on the biology of methanotrophs. We report the first complete genome sequence to our knowledge from an obligate methanotroph, Methylococcus capsulatus (Bath), obtained by the shotgun sequencing approach. Analysis revealed a 3.3-Mb genome highly specialized for a methanotrophic lifestyle, including redundant pathways predicted to be involved in methanotrophy and duplicated genes for essential enzymes such as the methane monooxygenases. We used phylogenomic analysis, gene order information, and comparative analysis with the partially sequenced methylotroph Methylobacterium extorquens to detect genes of unknown function likely to be involved in methanotrophy and methylotrophy. Genome analysis suggests the ability of M. capsulatus to scavenge copper (including a previously unreported nonribosomal peptide synthetase) and to use copper in regulation of methanotrophy, but the exact regulatory mechanisms remain unclear. One of the most surprising outcomes of the project is evidence suggesting the existence of previously unsuspected metabolic flexibility in M. capsulatus, including an ability to grow on sugars, oxidize chemolithotrophic hydrogen and sulfur, and live under reduced oxygen tension, all of which have implications for methanotroph ecology. The availability of the complete genome of M. capsulatus (Bath) deepens our understanding of methanotroph biology and its relationship to global carbon cycles. We have gained evidence for greater metabolic flexibility than was previously known, and for genetic components that may have biotechnological potential., Competing Interests: The authors have declared that no conflicts of interest exist.

Expression of surface-associated and secreted protein MopE of the methanotrophic bacterium Methylococcus capsulatus (Bath) in response to the concentration of copper ions in the growth medium was investigated. The level of protein associated with the cells and secreted to the medium changed when the copper concentration in the medium varied and was highest in cells exposed to copper stress.

From around 1500 and up to the end of the 19th century, when photographs were introduced and gradually took over, graphic artwork was widely used in medical literature. Graphic techniques allowed for interpretations by the artist in collaboration with the medical scientist. They provide important glimpses into the history of art, into cultural and medical history, and into the history of science. Based primarily on the collections of the Oslo University Library, this article presents some of the high points in this tradition.

Background: In the mid-19th century, Norwegian public services were expanded, among them asylums and prisons. The physician Frederik Holst (1791-1871) was instrumental in the development of both fields. He travelled extensively abroad studying public institutions and had considerable influence on the planning of a new modern penitentiary in Oslo, Botsfengselet, which opened in 1851., Material and Methods: The article is based on Holst's printed lectures and reports., Results: Holst was obviously influenced by the Enlightenment ideas of the 18th century and the contemporary international debate on prisons. He promoted panoptic asylums and prisons with good hygienic standards and the necessary degree of confinement. In the case of asylums, the panoptic principles were discarded before they were implemented, but the new Oslo prison was built as a panoptic institution and according to the Philadelphia system of one cell for each inmate., Interpretation: Holst's writing indicates a commitment to health issues, though he maintained that serving time in a prison was an intended punishment with social rehabilitation as the desired outcome.