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Healthcare jobs are very popular among women, however in Japan, women readily quit working because of gender-role responsibilities. This study aimed to develop a workplace support checklist for women to continue to work. In 2017, we investigated 780 (female 74.8%) faculty members and healthcare professionals of one medical university in Japan. We asked them to score the extent to which they considered 35 items identified by a task team, to be related to continuous work support for female workers in healthcare. We carried out an exploratory factor analysis and extracted four domains with 16 items in all: &ldquo, Support for child rearing and home care&rdquo, (five items), &ldquo, Information dissemination&rdquo, Active promotion of women workers to higher positions&rdquo, (three items), and &ldquo, Consulting and counseling service&rdquo, (three items), with Cronbach&rsquo, s alpha values ranging from 0.88 to 0.92. We found that the first three factors were generally associated with reasonably relevant characteristics of being female, in their 30s, married, and members of faculty. We also found that women with &ldquo, Intention to leave&rdquo, the workplace underscored the importance of &ldquo, and &ldquo, These results suggest that the checklist is reliable and valid.

The North Pacific spiny dogfish (SPD), Squalus suckleyi, is a commercially exploited shark species that plays an important role in the ecosystem. To elucidate the distribution of the SPD in the North Pacific and to evaluate the effects of sea surface temperature (SST) and prey availability on its distribution, we estimated the probability of SPD presence using a generalized additive model with a binomial error distribution from SPD presence/absence data on 14,824 operations in fishery-independent gillnet surveys between 1972 and 2011. The habitat model was structured in the east and west to reflect differences in the North Pacific oceanic environments. In the east, a higher probability of SPD presence was identified along the coast from the eastern Gulf of Alaska to Queen Charlotte Sound. In the west, it was identified around northern Japan. The estimated distribution was continuous between the two areas, whereas the probability of SPD presence was relatively low. Although the probability of SPD presence was higher at SSTs between 6°C and 12°C, the SST at the peak probability of SPD presence differed between the west and east. The prey species, Japanese sardine, Sardinops melanostictus, and walleye pollock, Gadus chalcogrammus, in the west and boreal clubhook squid, Onychoteuthis borealijaponica, in the east significantly affected the probability of SPD presence, which was higher if the prey species co-existed with SPD. Therefore, SPD might adapt their distribution to that of available prey species. SPD stock assessment and management in these two important areas are required for its sustainable utilization.

Objectives In academia, harassment may often occur and remain unrevealed in Japan, which discourages young researchers from pursuing their career. It is necessary to estimate and improve the perception of "academic harassment" among university faculties. Therefore, in this study, we aim to develop a scale of perception of academic harassment. Methods Prior to a quantitative survey, a task team consisting of medical doctors, researchers, nurses, hospital workers, and managers in general affairs division identified 36 items related to academic harassment. In February 2016, we sent a self-administered questionnaire to 1,126 academic faculty members who worked in a medical university located in Tokyo, Japan. We instructed them to score the extent to which they consider each item as related to academic harassment based on a Likert scale. We carried out maximum likelihood factor analyses with promax rotation and computed Cronbach's alpha to develop a scale and investigate the reliability of the scale. Results In total, 377 returned the questionnaires (response rate, 33.5%; male, 73.8%). In factor analyses, we removed 17 items owing to low factor loadings, and four factors were eventually extracted. The first factor was termed "Harassment in organization (7 items)" because it included conditions of forcing a particular person to work on chores or lectures for students that may prevent one's academic research outputs. The second factor was termed "Violence and denying personal character (4 items)". The third factor was termed "Research misconduct (5 items)" including conditions of excluding a particular person from the coauthor list of research outputs or pressuring a person to fabricate, falsify, or plagiarize research outputs. The fourth factor was termed "Research interference (3 items)" including a condition of interference with conference attendance. Cronbach's alpha values of these four factors ranged from 0.83 to 0.91, suggesting that the scale had high reliability. The means of these factors did not differ according to gender but were higher in participants aged 50 or older than in younger participants. Conclusions The results suggest that the scale of perception on academic harassment consisting of four factors with 19 items is valid and reliable to some extent.

In activated brain regions, the deoxygenated hemoglobin (deoxy-Hb) concentration decreases despite an increase in oxygen consumption. This is attributed to the fact that the cerebral blood flow (CBF) induced by neuronal activation exceeds the accompanying increase in the cerebral metabolic rate of oxygen (CMRO2). The discrepancy between large CBF and disproportionately small CMRO2 responses provides the basis for detecting the hemodynamic correlates of neuronal activities by functional magnetic resonance imaging (fMRI). However, this implies that if the supply of oxygen is made smaller than the oxygen consumed by the suppression of stimulus-induced CBF, the polarity of signals would be reversed. We used near-infrared spectroscopy (NIRS) to search for a condition wherein a marked decrease in the stimulus-evoked oxygenated Hb (oxy-Hb) concentration change was accompanied by an increase in the deoxy-Hb concentration in the human brain. We found that when a specific brain region was activated by two working memory (WM) task blocks in rapid succession, the local change in the deoxy-Hb concentration evoked by the second task block was reversed to an increase due to the refractory effect in the hemodynamic response. The result suggests that the polarity of the blood oxygenation level-dependent (BOLD) signal could change during repetitive neuronal activation, and thus caution must be taken in the interpretation of the BOLD signal under such situations.

OBJECTIVES To clarify the association between job stress and the number of physical symptoms among newly certified female nurses. METHODS In this cross-sectional self-administered survey, we investigated 313 female nurses working at three medical-university-affiliated hospitals in February 2016. We investigated working conditions including numbers of working and on-call hours, work-life balance, Job Content Questionnaire (JCQ) scores, and 16 physical symptoms perceived more often than once a week. RESULTS Among the 313 participants (mean age, 31.9), 57% were aged 21-29 years and 70% were single. Of the 16 physical symptoms investigated, fatigability was the most frequent complaint (66.1%), followed by lower back pain (44.7%). Univariate analysis showed that significant factors related to physical symptoms are job demands (p

Temperature-driven life-history modifications by adaptation occur in ectotherms, and therefore, life-history modifications by adaptation need to be taken into consideration when predicting population responses to the climate change. Partial migration is a common form of life-history diversity in which a population contains both migratory and resident behaviours. Salmonid fish exhibit a wide range of life-history diversity and, in particular, partial migration. We evaluated the effect of temperature-driven life-history modifications on population dynamics in partially migratory masu salmon (Oncorhynchus masou) by field observations and theoretical models. Field observations revealed that spatial patterns of alternative migratory tactics were associated with temperature gradients. The occurrence of resident males increased, whereas the proportion of migrant males and the proportion of delayed migrants including both sexes decreased with increasing temperature and, thereby, with improved early growth conditions. The expected fitness for each migratory tactic was computed in a life-history model with early growth conditions as a function. Individual fitness was maximized by adopting resident tactics under favourable early growth conditions, early migrant tactics under intermediate early growth conditions and delayed migrant tactics under unfavourable early growth conditions. The results suggest that individuals exhibited a status-dependent conditional strategy, that is, the adoption of alternative migratory tactics is influenced by the status of individuals to make the best of a situation. A simulation model suggests that increased residency by males to increased temperature leads to a substantial decrease in the number of migrants. Moreover, the decrease in the number of delayed (older) migrants with increasing temperature magnified fluctuations in abundance. Our findings indicate the importance of temperature-driven life-history modifications for predicting dynamics of natural populations under climate warming.

We evaluated the migratory patterns of white-spotted charr in eastern Hokkaido, Japan using: (1) field observation of fish, (2) salinity-recording archival tags, and (3) analysis of otolith Sr and Ca concentrations. Field observations suggest that the majority of anadromous white-spotted charr outmigrate to the sea in spring (April to June) and ascend the river between late summer and autumn (August to November). Salinity records from archival tags revealed a fluctuating pattern consisting of both low and high values within a month, indicating frequent short-term movements between freshwater (including non-natal rivers) and brackish/salt water habitats. Otolith Sr:Ca ratios exhibited a sharp rise at about 40–50% of the otolith radius, which was followed by several spikes consisting of both low and high values, indicating that fish migrated between freshwater and marine environments multiple times during their life history. However, the peaks in Sr:Ca ratios were generally associated with annulus zones on the otolith, indicating that the anadromous migration was generally an annual event.

The nitrilase gene of Rhodococcus rhodochrous J1 was expressed in Escherichia coli using the expression vector, pKK223-3. The recombinant E. coli JM109 cells hydrolyzed enantioselectively 2-methyl-2-propylmalononitrile to form (S)-2-cyano-2-methylpentanoic acid (CMPA) with 96 % e.e. Under optimized conditions, 80 g (S)-CMPA l(-1) was produced with a molar yield of 97 % at 30 °C after a 24 h without any by-products.

An extracellular lipase was isolated from a culture filtrate of Fusarium oxysporum f. sp. lini SUF 402 by hydrophobic chromatography. Purity of the preparation was 38-fold and recovery yield was 32%. The molecular mass of the isolated enzyme was 30 kDa. The lipase had a sugar chain, and the N-terminal amino acid was modified. The optimun pH at 37°C was 7.0. The enzyme had higher activity toward p-nitrophenyl esters with long and middle chain fatty acids (C8-C18) than with a short chain fatty acid (C4). The enzyme was not inhibited by phenylmethylsulfonyl fluoride or 2-mercaptoethanol. In the case of the lipase, both the hydrolysis rate of tristearin and final concentration of fatty acid content were higher than those of triolein. The lipase was examined with respect to its ability of concentrating the n-3 polyunsaturated fatty acid (n-3 PUFA) content of partially hydrolyzed glycerides (TG and DG) obtained from two kinds of fish oil (cod liver oil and refined sardine oil). The lipase gave increases in n-3 PUFA contents as the hydrolysis progressed. The lipase concentrated only docosahexaenoic acid with little increase in icosapentaenoic acid. Maximal total n-3 PUFA contents were about 30% in both fish oils.

A NADPH-dependent (S)-imine reductase (SIR) was purified to be homogeneous from the cell-free extract of Streptomyces sp. GF3546. SIR appeared to be a homodimer protein with subunits of 30.5 kDa based on SDS-polyacrylamide gel electrophoresis and HPLC gel filtration. It also catalyzed the (S)-enantioselective reduction of not only 2-methyl-1-pyrroline (2-MPN) but also 1-methyl-3,4-dihydroisoquinoline and 6,7-dimethoxy-1-methyl-3,4-dihydroisoquinoline. Specific activities for their imines were 130, 44, and 2.6 nmol min(-1) mg(-1), and their optical purities were 92.7 % ee, 96.4 % ee, and99 % ee, respectively. Using a NADPH-regenerating system, 10 mM 2-MPN was converted to amine with 100 % conversion and 92 % ee after 24 h. The amino acid sequence analysis revealed that SIR showed about 60 % identity to 6-phosphogluconate dehydrogenase. However, it showed only 37 % identity with Streptomyces sp. GF3587 (R)-imine reductase. Expression of SIR in Escherichia coli was achieved, and specific activity of the cell-free extract was about two times higher than that of the cell-free extract of Streptomyces sp. GF3546.

Washed cells (62 mg) of Kitasatospora sp. GF12 in 4 ml buffer (pH 7) catalyzed the regioselective hydroxylation of 60 mM 1,3-adamantanediol [1,3-ad(OH)(2)] to 30.9 mM 1,3,5-adamantanetriol [1,3,5-ad(OH)(3)] over 120 h at 24 °C. Glycerol at 400 mM was added to the reaction mixture to recycle the intracellular NADH/NADPH. Whole cells of GF12, also catalyzed the hydroxylation of 10 mM 1-adamantanol (1-adOH), to 3.6 mM 1,3,5-ad(OH)(3).

The (R)-imine reductase (RIR) of Streptomyces sp. GF3587 was purified and characterized. It was found to be a NADPH-dependent enzyme, and was found to be a homodimer consisting of 32 kDa subunits. Enzymatic reduction of 10 mM 2-methyl-1-pyrroline (2-MPN) resulted in the formation of 9.8 mM (R)-2-methylpyrrolidine ((R)-2-MP) with 99% e.e. The enzyme showed not only reduction activity for 2-MPN at neutral pH (6.5-8.0), but also oxidation activity for (R)-2-MP under alkaline pH (10-11.5) conditions. It appeared to be a sulfhydryl enzyme based on the sensitivity to sulfhydryl specific inhibitors. It was very specific to 2-MPN as substrate.

We examined seasonal changes in population densities of stream salmonids (masu salmon Oncorhynchus masou, white-spotted charr Salvelinus leucomaenis, and rainbow trout O. mykiss) in two tributaries of the Shoro River, eastern Hokkaido, Japan. In one small tributary, water temperature was relatively high during the winter, and populations of salmon and trout increased through immigration at this time of the year, becoming dominant components of the salmonid assemblage; the density of charr in this stream decreased during the winter, but charr was dominant during the summer. In another medium-sized tributary, the water temperature fell to close to 0°C during the winter, and densities of salmon and charr decreased in this season, through emigration; trout were very rare in this stream. Seasonal patterns of stream salmonid densities vary among species and between localities, resulting in seasonal changes in species composition. For a comprehensive understanding of population processes, a whole-river survey across seasons will be necessary.

To efficiently produce 1,3-adamantanediol (1,3-ad(OH)(2)) from 1-adamantanol (1-adOH), our stocks of culture strains and soil microorganisms were surveyed for hydroxylation activity towards 1-adOH. Among them, the soil actinomycete SA8 showing the highest hydroxylation activity was identified as Streptomyces sp. based on 16S ribosomal DNA sequence analysis. The reaction products were purified by silica gel column chromatography, and from NMR and MS analyses, they were identified as 1,3-ad(OH)(2) and 1,4-ad(OH)(2). Streptomyces sp. SA8 produced 5.9 g l(-1) 1,3-ad(OH)(2)from 6.2 g l(-1) 1-adOH in culture broth after 120 h at 25 degrees C. Using resting cells, 2.3 g l(-1) 1,3-ad(OH)(2) was produced after 96 h of incubation at a 69% conversion rate. In both cases, 1,4-ad(OH)(2) was formed as a byproduct at a rate of about 15%. Strain SA8 also hydroxylated 2-adamantanol and 2-methyl-2-adamantanol.

We examined latitudinal variation in riverine growth and parr maturation of an endemic Asian salmonid, masu salmon ( Oncorhynchus masou ), in 12 rivers located between 36.6°N and 45.4°N. Masu salmon parr showed considerable variation in growth and maturation patterns among populations. Body sizes were generally larger, and parr maturation was common at southern latitudes. Male parr matured at smaller sizes at more southern latitudes. Latitudinal variation in riverine growth and maturation of masu salmon parr was largely attributed to latitudinal changes in temperature and population density. Parr size at age increased with increasing temperature and decreased with population density. Riverine growth conditions were an important environmental factor determining parr maturation for both males and females; however, the occurrence of mature female parr required extremely favorable growth conditions. Water temperature in May, approximately four months before maturation, was the most important environmental factor affecting the maturation of male parr. Our study supports the hypothesis that freshwater residency was promoted by favorable growth conditions at southern latitudes.

Kidokoro, H., Goto, T., Nagasawa, T., Nishida, H., Akamine, T., and Sakurai, Y. 2010. Impact of a climate regime shift on the migration of Japanese common squid (Todarodes pacificus) in the Sea of Japan. – ICES Journal of Marine Science, 67: 1314–1322. Following a climate regime shift (RS) in 1989 in the northwest Pacific and Sea of Japan, the main spawning grounds of the Japanese common squid (Todarodes pacificus) shifted from inshore areas off Honshu Island to the Tsushima Strait, and the stock size increased. Migration patterns of T. pacificus occurred after the RS, based on tagging experiments conducted in July to September of 1984 and 1987–1991, are examined using monthly shifts in average latitude of recapture sites every 10 d. Before the RS, recaptures were in the central Sea of Japan and in inshore areas off Honshu Island, but after the RS, there were no recaptures inshore off Honshu Island. The average latitude of the recapture sites in September was about 36–37°N before the RS and north of 40°N (near the release sites) after the RS. It is likely that the location of the spawning grounds has changed.

To provide a key piece of information for understanding the functioning of the Bering Sea pelagic ecosystem, we estimated the biomass of immature chum salmon in the Bering Sea basin in autumn using a return-at-age analysis incorporated with the results of genetic stock identification studies. The estimated biomass was 742 000 t in 2002 and 617 000 t in 2003, which is possibly an underestimate because of the uncertainty of trawl selectivity parameters used in the estimation. Although chum salmon has been the dominant nekton species in the pelagic ecosystem of the Bering Sea basin in recent years, biomass estimates for the species were smaller than one-tenth of the max- imum biomass of walleye pollock in the 1980s. Previous studies have highlighted the importance of the huge biomass of mesopelagic planktivores, such as myctophid fishes and gonatid squid, to the ecosystem function of the pelagic Bering Sea. Planktivorous Pacific salmon including chum and pink salmon may also play a significant role as competitors and predators of small planktivores, thus affecting the dynamics of ecosystem function and nekton community structure in the pelagic Bering Sea.

Alkane-assimilating microorganisms were isolated from enrichment cultures using n-octane, n-dodecane, n-hexadecane, or pristane (2,6,10,14-tetramethylpentadecane) as a sole carbon source to find microbial catalysts oxidizing methyl groups of 2,6-dimethylpyridine. The cells of Exophiala dermatitidis (Kano) de Hoog DA5501, an n-dodecane-assimilating fungus, oxidized a single methyl group of 2,6-dimethylpyridine to produce 6-methylpicolinic acid (6-methylpyridine-2-carboxylic acid) without the formation of dipicolinic acid (pyridine-2,6-dicarboxylic acid); 67 mM 6-methylpicolinic acid (9.2 g/l) accumulated with a molar conversion yield of 89% by 54-h incubation. The fungus cells also oxidized the methyl group of 2,6-dimethylpyrazine and 2,4,6-trimethylpyridine regioselectively.

Many studies have investigated the ecology of charrs in freshwater, however, little is known about charrs in the ocean. This study examined the distribution, seasonal abundance, and some biological features of Dolly Varden (Salvelinus malma) in the Pacific Ocean. An analysis of by-catch data of Japanese offshore salmon monitoring showed that Dolly Varden were distributed across a wide range in the offshore waters of the Pacific Ocean, including the Japan Sea, Bering Sea, and Okhotsk Sea. The catch per unit effort showed a sharp increase from May to August, followed by a sharp decrease in September. Offshore areas served as an important summer habitat for anadromous Dolly Varden.

Latitudinal variation in egg size and number in anadromous masu salmon Oncorhynchus masou was examined. Relatively greater variation in egg size occurred among rivers than among females within rivers or within females. Egg size was generally greater and egg number generally lower at more northerly latitudes.

Fukuwaka, M., Azumaya, T., Davis, N. D., and Nagasawa, T. 2008. Bias in size composition of chum salmon (Oncorhynchus keta) caught by a gillnet with a geometric series of mesh sizes, and its correction using gear intercalibration. – ICES Journal of Marine Science, 65: 930–936. Some research gillnets with size combinations based on a geometric series have been used for research surveys underpinning the stock assessment of fresh-water and marine fish. We assessed a bias in size composition of chum salmon caught using a research gillnet consisting of ten different mesh sizes based on a geometric series of factor 1.14. In all, 11 fishing operations were conducted for gear intercalibration between the research gillnet and a midwater trawl in the central Bering Sea. The best-fit selectivity model to pooled catch data included different fishing intensities among gillnet meshes. The pooled catch efficiency and the maximum catch efficiency of the gillnet increased with fish size. Estimated size composition of chum salmon was more similar to trawl catches than to research gillnet catches. Bias in size composition of research gillnet catches may be caused by the difference in encounter probability among mesh sizes, variability in fish swimming speed based on fish size, mesh visibility influencing fish behaviour, and diel vertical migration of chum salmon. When conducting multimesh gillnet surveys for stock assessment, researchers should correct a bias in size composition by performing gear intercalibrations.

The larval and juvenile stages of Sebastes taczanowskii (Japanese name: Ezo-mebaru) are described and illustrated based on 33 wild specimens [7.1–26.9 mm in body length (BL)] collected in the Sea of Japan, and eight specimens of reared larvae extruded from the one specimen of a captive pregnant female. Larvae were extruded between 4.3–5.0 mm BL and notochord flexion occurred 5.7–9.0 mm BL. Transformation from postflexion larvae to pelagic juveniles occurred between 13 and 17 mm BL. Preflexion and flexion larvae have a single melanophore row on the dorsal surface on the tail, and an internal line of melanistic dashes on the ventral side of the tail. Lateral pigmentation of postflexion and transforming larval body surfaces are light. Compared with other Japanese rockfish species, S. taczanowskii is shallow-bodied throughout both larval and juvenile stages. We provide an identification key to preflexion and flexion stage rockfish larvae found around the Japanese archipelago, and comparisons with other species. Larval and juvenile S. taczanowskii occurred in both near-shore and relatively offshore water around Shakotan Peninsula-Ishikari Bay, Hokkaido in June and July.

The isoeugenol monooxygenase gene of Pseudomonas putida IE27 was inserted into an expression vector, pET21a, under the control of the T7 promoter. The recombinant plasmid was introduced into Escherichia coli BL21(DE3) cells, containing no vanillin-degrading activity. The transformed E. coli BL21(DE3) cells produced 28.3 g vanillin/l from 230 mM isoeugenol, with a molar conversion yield of 81% at 20 degrees C after 6 h. In the reaction system, no accumulation of undesired by-products, such as vanillic acid or acetaldehyde, was observed.

trans-Stilbene degradation was examined by the reaction using resting cells of microorganisms isolated through the enrichment culture using trans-stilbene. The strain SL3, showing the highest trans-stilbene-degrading activity, was identified as Arthrobacter sp. One of the reaction products was identified to be cis,cis-muconic acid. Arthrobacter sp. SL3 cells also transformed benzaldehyde, benzoic acid and catechol into cis,cis-muconic acid, suggesting that one benzene ring of trans-stilbene was converted into cis,cis-muconic acid via benzaldehyde formed by its C(alpha)=C(beta) bond cleavage.

Microbial asymmetric oxidation of 2-butyl-1,3-propanediol was investigated for an efficient synthesis of S- and R-enantiomers of 2-hydroxymethylhexanoic acid (2-HMHA). From an intensive survey of the stocked bacterial strains, Acetobacter pasteurianus IAM 12073 and Pseudomonas putida IFO 3738 were found to show the highest S- and R-2-HMHA-producing activity, respectively. Under optimized conditions, A. pasteurianus (351 mg dry cell weight) and P. putida (642 mg dry cell weight) cells produced 12.0 g l(-1) S-2-HMHA with 89% enantiomeric excess (e.e.) at 24 h of incubation and 5.1 g l(-1) R-2-HMHA with 94% e.e. at 35 h of incubation from 2-butyl-1,3-propanediol.

The ability to produce vanillin and/or vanillic acid from isoeugenol was screened using resting cells of various bacteria. The vanillin- and/or vanillic-acid-producing activities were observed in strains belonging to the genera Achromobacter, Aeromonas, Agrobacerium, Alcaligenes, Arthrobacter, Bacillus, Micrococcus, Pseudomonas, Rhodobacter, and Rhodococcus. Strain IE27, a soil isolate showing the highest vanillin-producing activity, was identified as Pseudomonas putida. We optimized the culture and reaction conditions for vanillin production from isoeugenol using P. putida IE27 cells. The vanillin-producing activity was induced by adding isoeugenol to the culture medium but not vanillin or eugenol. Under the optimized reaction conditions, P. putida IE27 cells produced 16.1 g/l vanillin from 150 mM isoeugenol, with a molar conversion yield of 71% at 20 degrees C after a 24-h incubation in the presence of 10% (v/v) dimethyl sulfoxide.

We found the occurrence of 4-hydroxybenzoate decarboxylase in Enterobacter cloacae P240, isolated from soils under anaerobic conditions, and purified the enzyme to homogeneity. The purified enzyme was a homohexamer of identical 60 kDa subunits. The purified decarboxylase catalyzed the nonoxidative decarboxylation of 4-hydroxybenzoate without requiring any cofactors. Its K m value for 4-hydroxybenzoate was 596 μM. The enzyme also catalyzed decarboxylation of 3,4-dihydroxybenzoate, for which the K m value was 6.80 mM. In the presence of 3 M KHCO3 and 20 mM phenol, the decarboxylase catalyzed the reverse carboxylation reaction of phenol to form 4-hydroxybenzoate with a molar conversion yield of 19%. The K m value for phenol was calculated to be 14.8 mM. The gene encoding the 4-hydroxybenzoate decarboxylase was isolated from E. cloacae P240. Nucleotide sequencing of recombinant plasmids revealed that the 4-hydroxybenzoate decarboxylase gene codes for a 475-amino-acid protein. The amino acid sequence of the enzyme is similar to those of 4-hydroxybenzoate decarboxylase of Clostridium hydroxybenzoicum (53% identity), VdcC protein (vanillate decarboxylase) of Streptomyces sp. strain D7 (72%) and 3-octaprenyl-4-hydroxybenzoate decarboxylase of Escherichia coli (28%). The hypothetical proteins, showing 96–97% identities to the primary structure of E. cloacae P240 4-hydroxybenzoate decarboxylase, were found in several bacterial strains.

We found a bacterium, Pandoraea sp. 12B-2, of which whole cells catalyzed not only the decarboxylation of 2,6-dihydroxybenzoate but also the regioselective carboxylation of 1,3-dihydroxybenzene to 2,6-dihydroxybenzoate. The whole cells of Pandoraea sp. 12B-2 also catalyzed the regioselective carboxylation of phenol and 1,2-dihydroxybenzene to 4-hydroxybenzoate and 2,3-dihydroxybenzoate, respectively. The molar conversion ratio of the carboxylation reaction depended on the concentration of KHCO(3) in the reaction mixture. Only 5 or 48 % of 1,3-dihydroxybenzene added was converted into 2,6-dihydroxybenzoate in the presence of 0.1 M or 3 M KHCO(3), respectively. The addition of acetone to the reaction mixture increased the initial rate of the carboxylation reaction, but the final molar conversion yield reached almost the same value. When the efficient production of 2,6-dihydroxybenzoate was optimized using the whole cells of Pandoraea sp. 12B-2, the productivity of 2,6-dihydroxybenzoate topped out at 1.43 M, which was the highest value so far reported. No formation of any other products was observed after the carboxylation reaction.

Epsilon-poly-L-lysine (epsilon-PL) is one of the few naturally occurring biopolymers and is characterized by a peptide bond between the alpha-carboxyl and epsilon-amino groups. Previously, we purified and characterized the epsilon-PL-degrading enzyme (Pld) from Streptomyces albulus, which is an epsilon-PL producer, and this enzyme was expected to confer self-resistance to the epsilon-PL produced by the organism itself. The gene encoding Pld was cloned based on the N-terminal amino acid sequence determined in this study, and a sequencing analysis revealed eight open reading frames (ORFs), i.e., ORF1 to ORF8 in the flanking region surrounding the pld gene (present in ORF5). To investigate the biological function of Pld, we constructed a knockout mutant in which the pld gene is inactivated. Studies on epsilon-PL susceptibility, epsilon-PL-degrading activity, and epsilon-PL productivity demonstrated that the pld gene does play a partial role in self-resistance and that S. albulus was found to produce other epsilon-PL-degrading enzyme(s) in addition to Pld. To the best of our knowledge, this is the first report on a self-resistance gene for a biopolymer possessing antibacterial activity.

Hatchery programmes involving the mass release of cultured fish have been implemented worldwide to supplement wild populations and to increase harvests. Hokkaido Island is one of the most active regions for Pacific salmon hatchery programmes, with ca. 1.2 billion (109) juveniles released annually along a coastline of ca. 3000 km. During the last quarter of the 20th century, coastal catches of chum and pink salmon increased dramatically, whereas those of masu salmon did not. In addition to the development of hatchery technologies, several possible hypotheses may explain these catch trends, including climate change, closing of high-seas fisheries, rehabilitation of water quality, habitat loss caused by damming and channelling, and increased pressure from recreational fisheries. Even when these other factors have been accounted for, it is difficult to evaluate whether all hatchery programmes have actually increased net populations. To use these programmes more effectively, it is necessary to evaluate both their river- and species-specific benefits and compare hatchery programmes with other management tools, such as fishery controls and habitat rehabilitation. Future hatchery programmes should incorporate active, adaptive learning approaches to minimize the risks associated with artificial propagation and to promote sustainable salmon stocks.

Mucor circinelloides and Mortierella isabellina hydroxylated dehydroabietic acid (DehA). DehA was converted regio- and stereo-selectively by whole cells of Mr. circinelloides to give 2alpha-hydroxydehydroabietic acid in a 75% molar conversion yield (11 mM from 14.7 mM DehA) after 72 h in the cultivation medium containing 3% (v/v) Tween 80. With cells of Ma. isabellina, under the same conditions, 20.5 mM (6.5 g l(-1)) 2-hydroxydehydroabietic acid (alpha/beta=81/19) was formed from 26.4 mM DehA.

Verticillium sp. GF39, catalyzing the oxidation of 1-methylisoquinoline to 1-methylisoquinoline N-oxide, was found to be the highest N-oxide producer. Under the optimized reaction conditions, the whole cells of Verticillium sp. GF39 formed 5 mM 1-methylisoquinoline N-oxide from 1-methylisoquinoline with a molar conversion yield of 100% after a 10-h incubation at 20°C. The whole cells also acted on pyridine, 2-methylpyridine, quinoline and isoquinoline and formed the corresponding N-oxides.

Conversion of heterocyclic and aromatic aldehydes to the corresponding carboxylic acids was carried out using Acetobacter rancens IFO3297, A. pasteurianus IFO13753 and Serratia liquefaciens LF14. IFO3297 produced 110 g 2-furoic acid l(-1) from furfural with a 95% molar yield. 5-Hydroxymethyl-2-furancarboxylic acid was produced from the corresponding aldehyde by using whole cells LF14. IFO13753 and LF14 both converted isophthalaldehyde, 2,5-furandicarbaldehyde, 2,5-thiophenedicarbaldehyde and 2,2' biphenyldicarbaldehyde to the corresponding formylcarboxylic acid with 86-91% molar yields.

Viscosity of molten silicon has been measured to study the behavior, especially around the melting point, in order to supply useful information for the crystal growth of semiconductors. The temperature range was taken as wide as possible from 1891 K down to the supercooled region by using an oscillating viscometer with various materials of crucible to study the effect of the materials. It has been clear that the viscosity of molten silicon showed a good Arrhenian behavior in the entire temperature range including the supercooled region and no abnormal increase around the melting point. The viscosity values were lower than the reported values and the maximum difference reached 50% even in the temperatures sufficiently higher than the melting point. Furthermore, almost no effect on the measurement by the materials of crucible was found. The recommended viscosity is presented by the following equation based on the present results: log η /mPa s =−0.727+819/T, E η =15.7 kJ mol −1 . The viscosity and the activation energy were considerably lower than those of other metals with high melting points and the reason was considered to be due to the looser structure of the molten silicon originated from diamond-type solid structure.

A thermophilic and cyanide ion-tolerant bacterium, Bacillus stearothermophilus CN3 isolated from a hot spring in Japan, was found to produce thermostable beta-cyano-L-alanine synthase. The enzyme catalyzes the synthesis of beta-cyano-L-alanine from O-acetyl-L-serine and cyanide ions. The purified enzyme has a molecular mass of approximately 70 kDa and consists of two identical subunits. It was stable in the pH range of 6.0 to 10.0 and up to 70 degrees C. The enzyme also catalyzes the synthesis of various beta-substituted-L-alanine derivatives from O-acetyl-L-serine and nucleophilic reagents. The gene encoding the beta-cyano-L-alanine synthase was isolated from B. stearothermophilus CN3. Sequence homology analysis revealed that the beta-cyano-L-alanine synthase of the bacterium is O-acetyl-L-serine sulfhydrylase. A recombinant plasmid, constructed by ligation of the cloned gene and an expression vector, pKK223-3, was introduced into E. coli JM109. The transformed E. coli cells overexpressed beta-cyano-L-alanine synthase. Heat stable beta-cyano-L-alanine synthase can be applied to the synthesis of [4-11C]l-2,4-diaminobutyric acid as a tracer for positron emission tomography.

A thermophilic and cyanide ion-tolerant bacterium, Bacillus stearothermophilus CN3 isolated from a hot spring in Japan, was found to produce thermostable γ-cyano-α-aminobutyric acid synthase. The enzyme was purified and characterized. The purified enzyme has a molecular mass of approximately 180 kDa and consists of four identical subunits. It was stable in the pH range of 6.0 to 10.5 and up to 60°C. The enzyme catalyzed the γ-replacement reaction of O-acetyl- l -homo-serine with cyanide ions. The gene encoding the γ-cyano-α-aminobutyric acid synthase was isolated from B. stearothermophilus CN3. Sequence homology analysis revealed that the γ-cyano-α-aminobutyric acid synthase from the bacterium is O-acetyl- l -homoserine sulfhydrylase. A recombinant plasmid, constructed by ligation of the cloned gene and an expression vector, was introduced into Escherichia coli JM109. The transformed E. coli cells overexpressed γ-cyano-α-aminobutyric acid synthase. The heat stable γ-cyano-α-aminobutyric acid synthase can be applied to the synthesis of [5-11C] l -glutamic acid used as a tracer for positron emission tomography.

An epsilon-poly-L-lysine-degrading enzyme of an epsilon-poly-L-lysine-producing strain of Streptomyces albulus was purified and characterized. The enzyme was tightly bound to the cell membrane. After solubilization with NaSCN, the enzyme was purified to homogeneity by phenyl-Sepharose CL-4B column chromatography. The subunit molecular mass of the purified enzyme was 54 kDa. Enzyme activity was inhibited by o-phenanthroline, and could be restored in the presence of 1 mM Mg(2+), Ca(2+), Fe(3+) or Zn(2+). The mode of epsilon-poly-L-lysine degradation was of the exo-type, and the enzyme released N-terminal L-lysines one by one. The enzyme acted on various peptides possessing L-lysine residues at the N-terminus and was classified as an aminopeptidase. Epsilon-Poly-L-lysine-degrading activity was found in the membrane fraction of some other Streptomyces strains as well as that of Streptomyces albulus. Streptomyces virginiae IFO 12827 and Streptomyces norsei IFO 15452 exhibited high epsilon-poly-L-lysine-degrading activity, and both strains could produce epsilon-poly-L-lysine, indicating a correlation between the distribution of membrane-bound epsilon-poly-L-lysine-degrading enzyme and epsilon-poly-L-lysine-producing activity.

Many research and development projects on high-temperature superconducting apparatus such as a transformer, fault current limiter, and cable are being actively pursued in the power field as a result of performance improvement of Bi silver sheath high-temperature superconducting (HTS) wire. HTS transformers are considered to be among the most promising applications in view of efficiency improvement, the interface with cryogenic cable and normal temperature devices, incombustibility, overload capability, the function as a reactor, and the possibility of use as a fault current limiter. The necessary technical development items of an HTS transformer in order to achieve performance superior to conventional devices are examined. For this purpose, three-phase 66-kV 100-MVA transformers were designed for the comparison of an HTS transformer and a conventional one with oil cooling. The desirable development items are an HTS wire current density of about 40 A/mm2, an allowable winding strain of about 0.5%, a percent impedance of 7.5%, an air gap flux density of about 0.3 T, and AC losses of about 0.3 W/km-A. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(1): 25–31, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10087

We studied the technical design targets of high temperature superconducting (HTS) large capacity transformers through the design of 3-phase 66 kV–100 MVA transformers, expecting further performance progress of HTS tapes. It is required for large capacity transformers installed in a power system to have enough percent impedance %IX in order to limit a fault current in the power system at the time of a short circuit accident. It is not easy at the present technical level for HTS transformers wound with Bi-2223/Ag tapes to secure enough percent impedance due to low air gap fields. The design targets are a percent impedance of 7.5%, an air gap flux density of 0.3 T, tape current density of about 40 A/mm 2 , winding strain of about 0.5% and AC losses of about 0.3 W/km A.