Comparative Proteomic Analysis of Methanothermobacter themautotrophicus ΔH in Pure Culture and in Co-Culture with a Butyrate-Oxidizing Bacterium

To understand the physiological basis of methanogenic archaea living on interspecies H2 transfer, the protein expression of a hydrogenotrophic methanogen, Methanothermobacter thermautotrophicus strain ΔH, was investigated in both pure culture and syntrophic coculture with an anaerobic butyrate oxidizer Syntrophothermus lipocalidus strain TGB-C1 as an H2 supplier. Comparative proteomic analysis showed that global protein expression of methanogen cells in the model coculture was substantially different from that of pure cultured cells. In brief, in syntrophic coculture, although methanogenesis-driven energy generation appeared to be maintained by shifting the pathway to the alternative methyl coenzyme M reductase isozyme I and cofactor F420-dependent process, the machinery proteins involved in carbon fixation, amino acid synthesis, and RNA/DNA metabolisms tended to be down-regulated, indicating restrained cell growth rather than vigorous proliferation. In addition, our proteome analysis revealed that α subunits of proteasome were differentially acetylated between the two culture conditions. Since the relevant modification has been suspected to regulate proteolytic activity of the proteasome, the global protein turnover rate could be controlled under syntrophic growth conditions. To our knowledge, the present study is the first report on N-acetylation of proteasome subunits in methanogenic archaea. These results clearly indicated that physiological adaptation of hydrogenotrophic methanogens to syntrophic growth is more complicated than that of hitherto proposed

The Hyper Suprime-Cam SSP survey: Overview and survey design

Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2-m Subaru telescope on the summit of Mauna Kea in Hawaii. A team of scientists from Japan, Taiwan, and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg2 in five broad bands (grizy), with a 5 σ point-source depth of r ≈ 26. The Deep layer covers a total of 26 deg2 in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg2). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey

Specific DNA Binding of a Potential Transcriptional Regulator, Inosine 5′-Monophosphate Dehydrogenase-Related Protein VII, to the Promoter Region of a Methyl Coenzyme M Reductase I-Encoding Operon Retrieved from Methanothermobacter thermautotrophicus Strain ΔH▿

Two methyl coenzyme M reductases (MCRs) encoded by the mcr and mrt operons of the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus ΔH are expressed in response to H2 availability. In the present study, cis elements and trans-acting factors responsible for the gene expression of MCRs were investigated by using electrophoretic mobility shift assay (EMSA) and affinity particle purification. A survey of their operator regions by EMSA with protein extracts from mrt-expressing cultures restricted them to 46- and 41-bp-long mcr and mrt upstream regions, respectively. Affinity particle purification of DNA-binding proteins conjugated with putative operator regions resulted in the retrieval of a protein attributed to IMP dehydrogenase-related protein VII (IMPDH VII). IMPDH VII is predicted to have a winged helix-turn-helix DNA-binding motif and two cystathionine β-synthase domains, and it has been suspected to be an energy-sensing module. EMSA with oligonucleotide probes with unusual sequences showed that the binding site of IMPDH VII mostly overlaps the factor B-responsible element-TATA box of the mcr operon. The results presented here suggest that IMPDH VII encoded by MTH126 is a plausible candidate for the transcriptional regulator of the mcr operon in this methanogen

Employment-related difficulties and distressed living condition in patients with hepatitis B virus: A qualitative and quantitative study

Abstract Background In Japan, an estimated 400,000 people have the hepatitis B virus (HBV), many of whom were infected as a result of group vaccinations. People with HBV face many challenges, including disease progression, employment-related difficulties, and increased medical expenses. The relationship between HBV victims’ daily life suffering and poverty associated with HBV-related employment changes has not been examined. We aimed to clarify the employment-related hardships experienced by Japanese HBV victims, and the relationships between these hardships and daily life suffering, including poverty, through qualitative and quantitative analyses. Methods The study population comprised 11,046 people infected with HBV via group vaccination who filed lawsuits in Japan’s District Courts by 2014. First, we conducted a qualitative study (2013) using the KJ method, with 107 participants (68 men, mean age 58.9 years; 39 women, mean age 55.3 years). Semi-structured interviews were conducted covering participants’ current condition, treatment, medical expenses, and life difficulties (employment- and family-related problems). In 2014, we conducted a quantitative study. We mailed questionnaires to the entire study population, investigating the topics covered in the interviews (response rate 60.1%). Daily life suffering was determined by responses to the question “What do you think about your everyday life situation?” We performed binomial logistic regression analyses to verify the relationships between daily life suffering and disease, employment, and income status. Results Interview data were integrated into seven islands: intention to work, lack of understanding of HBV in the workplace, inability to buy life insurance, burden due to medical expenses, life failure, dissatisfaction with the system, and wishing for life balance. The quantitative analyses showed significant positive correlations between daily life suffering and liver cancer (odds ratio [OR] 1.47, 95% confidence interval [CI]: 1.00–2.17, p < 0.05), being a part-time/casual employee (OR 1.46, 95% CI: 1.11–1.92 p < 0.01), and an income below the national average (p < 0.01). Conclusion We qualitatively and quantitatively demonstrated that employment-related hardships and daily life suffering are prevalent in people with HBV. Their likelihood of experiencing distress in daily life increases with increasing medical expenses, insecure employment status (e.g., job loss) attributable to HBV, and the resulting poverty