The surface heat flux over the Sea of Okhotsk has been calculated from 1987 to 2001 by bulk parameterizations using ECMWF, ISCCP, and GISST data, corrected by COADS data. Sea ice concentration and ice type are incorporated by using an SSM/I open water and thin-ice algorithm to better represent the sea ice conditions. The mean seasonal variation of the net heat flux, averaged over the entire Okhotsk Sea, ranges from a summer maximum of 158 W m À2 in June (a positive value indicates that the sea or sea ice gains heat form the air), to a winter minimum of À219 W m À2 in December. The seasonal geographic distribution of the net heat flux is determined mostly by turbulent (sensible and latent) heat flux. Because of the heat insulating effect of sea ice, the turbulent heat flux and accordingly the net heat flux has the largest variation in winter, particularly in the north region, reflecting the yearly difference of sea ice extent. The geographic distribution of the annual net heat flux shows a distinct contrast, significant cooling of the ocean in the north and net heating of the ocean in the south. This contrast is a result of heat transport by both sea ice and the southward East Sakhalin Current; sea ice formed by obtaining negative latent heat in the north is transported to the south, then it releases the negative latent heat by melting. The annual net heat budget is estimated to be À22 W m À2 averaged over the entire sea. The Okhotsk Sea loses heat to the atmosphere on an annual basis, although at least the order of 20 W m À2 error exists in the estimation. A trial was performed to estimate sea ice production using the heat budget calculation. The results suggest that most of the production occurs in open water and thin ice areas. The highest production area is located over the northwest shelf, within 100 km of the coast.

A novel peptide isomerase was purified from the venom of funnel web spider, Agelenopsis aperta. The complete primary structure of the isomerase has been established by sequence analyses of polypeptide chains, assignments of disulfide bridges, carbohydrate analyses, and mass spectrometry of sugar chains. The isomerase was found to be a 29-kDa polypeptide that consists of an 18-residue light chain and a 243-residue heavy chain connected by a single disulfide bridge. The heavy chain contains three intramolecular disulfide bridges and one N-linked oligosaccharide chain with a simple trimannosyl core structure. A sequence homology search showed a significant similarity of the enzyme with serine proteases, particularly around a putative catalytic triad of the isomerase. The isomerase specifically interconverts the configuration of Ser46 of a 48-amino-acid peptide, omega-agatoxin-TK, and the conversion rate from L-Ser to D-Ser was approximately two times faster than the reverse reaction.

The purpose of the present study was to investigate the effect of the coformer difference on particle surface solution-mediated phase transformation (PS-SMPT) during cocrystal particle dissolution in aqueous media in the absence and presence of polymers. SMPT can occur either in the bulk phase or at the particle surface because drug molecules can be supersaturated at the dissolving cocrystal surface, as well as in the bulk phase. Previously, bulk phase SMPT has been primarily investigated in formulation development. However, little is known about the effects of coformers and polymers on PS-SMPT of cocrystals. In this study, six carbamazepine (CBZ) cocrystals were used as model cocrystals (malonic acid (MAL), succinic acid (SUC), glutaric acid (GLA), adipic acid (ADP), saccharin (SAC), and nicotinamide (NCT); nonsink dissolution tests were performed with or without a precipitation inhibitor (hydroxypropyl methylcellulose (HPMC)) at pH 6.5. The residual particles were analyzed by powder X-ray diffraction, differential scanning calorimetry, polarized light microscopy (PLM), and scanning electron microscopy. Real-time PLM was used to directly observe rapid PS-SMPT. In the absence of HPMC, supersaturation was not observed in the bulk phase for all cocrystals. All cocrystals rapidly transformed to CBZ dihydrate aggregates via PS-SMPT (mostly within 1 min). In contrast, in the presence of 0.1% HPMC, supersaturation was observed for CBZ-SUC, CBZ-ADP, CBZ-SAC, and CBZ-NCT but not for CBZ-MAL and CBZ-GLA. The cocrystals with lower solubility coformers tended to induce higher supersaturation in the bulk phase. The PS-SMPT of CBZ-SUC, CBZ-ADP, and CBZ-SAC was slowed down by HPMC. By suppressing PS-SMPT, the cocrystals exhibited its supersaturation potential, depending on the properties of each coformer. To take advantage of the supersaturation potential of cocrystals to improve oral drug absorption, it is important to suppress particle surface SMPT in addition to bulk phase SMPT.

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Even in the current era of metagenomics, the interpretation of nucleotide sequence data is primarily dependent on knowledge obtained from a limited number of microbes isolated in pure culture. Thus, it is of fundamental importance to expand the variety of strains available in pure culture, to make reliable connections between physiological characteristics and genomic information. In this study, two sulfur oxidizers that potentially represent two novel species were isolated and characterized. They were subjected to whole-genome sequencing together with 7 neutrophilic and chemolithoautotrophic sulfur-oxidizing bacteria. The genes for sulfur oxidation in the obtained genomes were identified and compared with those of isolated sulfur oxidizers in the classes Betaproteobacteria and Gammaproteobacteria . Although the combinations of these genes in the respective genomes are diverse, typical combinations corresponding to three types of core sulfur oxidation pathways were identified. Each pathway involves one of three specific sets of proteins, SoxCD, DsrABEFHCMKJOP, and HdrCBAHypHdrCB. All three core pathways contain the SoxXYZAB proteins, and a cytoplasmic sulfite oxidase encoded by soeABC is a conserved component in the core pathways lacking SoxCD. Phylogenetically close organisms share same core sulfur oxidation pathway, but a notable exception was observed in the family ‘ Sulfuricellaceae ’. In this family, some strains have either core pathway involving DsrABEFHCMKJOP or HdrCBAHypHdrCB, while others have both pathways. A proteomics analysis showed that proteins constituting the core pathways were produced at high levels. While hypothesized function of HdrCBAHypHdrCB is similar to that of Dsr system, both sets of proteins were detected with high relative abundances in the proteome of a strain possessing genes for these proteins. In addition to the genes for sulfur oxidation, those for arsenic metabolism were searched for in the sequenced genomes. As a result, two strains belonging to the families Thiobacillaceae and Sterolibacteriaceae were observed to harbor genes encoding ArxAB, a type of arsenite oxidase that has been identified in a limited number of bacteria. These findings were made with the newly obtained genomes, including those from 6 genera from which no genome sequence of an isolated organism was previously available. These genomes will serve as valuable references to interpret nucleotide sequences.

Methanogenesis megacomplex An important first step in methanogenesis is the conversion of carbon dioxide to a reduced one-carbon formyl unit that is a substrate for downstream steps. This reaction is catalyzed by a complex of enzymes, including components for oxidizing hydrogen or formate and splitting two electrons along different energetic paths. Watanabe et al . carefully purified and prepared anaerobic cryo–electron microscopy samples of the enzyme complex responsible, resulting in a three-megadalton hexameric structure at 3- to 3.5-ångström resolution. The arrangement of iron–sulfur cofactors provides an explanation for how electron bifurcation is coupled to large protein motions, which are expected from the multiple conformational states present. —MAF

A sulfur-oxidizing bacterium, strain TTN T , was isolated from a Thioploca sample obtained from a freshwater lake in Japan. The isolate shared 97.1 % 16S rRNA gene sequence similarity with an obligately aerobic chemolithoautotroph, 'Thiobacillus plumbophilus' Gro7 T. Cells were rods, motile, and Gram-stain-negative. The G+C content of the genomic DNA was approximately 66 mol%. Strain TTN T grew over a temperature range of 8-32 6C (optimum 22-25 6C), an NaCl concentration range of 0-133.3 mM (optimum 0-3.3 mM) and a pH range of 5.3-8.6 (optimum pH 6.4-7.0). Strain TTN T was facultatively anaerobic and could utilize nitrate as an electron acceptor. The isolate oxidized tetrathionate, thiosulfate and elemental sulfur as the sole energy sources for autotrophic growth, and could also grow heterotrophically on a number of organic substrates. Based on its phylogenetic and phenotypic properties, strain TTN T represents a novel species of a novel genus, for which the name Sulfuriferula multivorans gen. nov., sp. nov. is proposed. The type strain is TTN T (5NBRC 110683 T 5DSM 29343 T). Along with this, the reclassification of 'Thiobacillus plumbophilus' as Sulfuriferula plumbophilus sp. nov. (type strain Gro7 T 5NBRC 107929 T 5DSM 6690 T) is proposed. Based on the data obtained in this study, we describe the designations Sulfuricellaceae fam. nov. and Sulfuricellales ord. nov. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain TTN T is LC005593. The accession numbers for the sqr, soxB, dsrA, and aprA sequences of strain TTN T are LC005597, LC005595, LC005596 and LC005594, respectively. Four supplementary figures are available with the online Supplementary Material.

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