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41.
Gassericin A, a bacteriocin produced by Lactobacillus gasseri LA39, has a cyclic structure linking N‐ and C‐terminal amino acids. Gassericin A was expressed in Escherichia coli JM109 as a biotinylated fusion protein on the basis of the DNA sequence of mature bacteriocin. A positive clone accumulated the bacteriocin, with no activity, as a soluble fusion protein in the cytoplasm. After release of an N‐terminal tag with factor Xa protease, gassericin A was converted into an active peptide having N‐ and C‐termini. The total amount of purified bacteriocins (expressed and native) was 480 µg/L and 370 µg/L, respectively. However, the specific activity of expressed gassericin A was 15 AU/mg lower than that of native bacteriocin (2600 AU/mg). Although the actual Mr (molecular weight) of the expressed bacteriocin should be 5666, the peptide showed the same mobility (Mr 3800) in sodium dodecylsulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) as native cyclic gassericin A, suggesting that the expressed peptide retains compact folding of the molecule similar to that of native gassericin A.  相似文献   
42.
Myostatin, a member of the transforming growth factor‐β superfamily, is a well known negative regulator of skeletal muscle growth. In the present study, the 6660 bp nucleotide sequence of the myostatin gene in Japanese Black cattle (JBC), including the entire coding region of 1128 bp, was determined. The amino acid sequence deduced from the nucleotide sequence of JBC was well conserved with its sequence of other cattle, although it was found that an Α→G transition at nucleotide position 641 results in the substitution of asparagine by serine at amino acid position 214. In order to examine the expression pattern of the myostatin gene in the skeletal muscles of JBC, its expression in three skeletal muscles, Semitendinosus (ST) muscle, Biceps femoris muscle and Longissimus lumborum muscle, of fetal and calf stages was analyzed by real time polymerase chain reaction. The highest level of the myostatin expression was observed in the fetal stage. In calf stages the highest expression was observed in ST muscle compared with the other two muscles. These results suggest that a higher expression of myostatin gene, especially in the fetal stage and in ST muscle during calf stages, is involved in the arrest in skeletal muscle growth and that its functional domains and genomic structure in JBC are well conserved with those in other mammals.  相似文献   
43.
Telemetry is a useful technique for elucidating salmon behavior, but the recovery periods before fish can be safely released after the attachment of telemetry devices have not yet been established. Reported recovery times vary widely, from 2 h to 13 days. We examined how anesthesia and surgery to attach external electromyogram (EMG) transmitters affected chum salmon (Oncorhynchus keta) recovery based on three physiological parameters. Fish subjected to anesthesia plus EMG transmitter attachment (EMG group), anesthesia only (AO group), and no handling (control) were placed in a swim tunnel. Critical swimming speed (U crit), oxygen consumption (MO2), and muscle activity (EMG values) were assessed 0, 1, 6, 12, 24, and 30 h after treatment. The MO2 in the EMG and AO groups was higher than in the control group 1 h after treatment, but did not differ significantly from the control in all subsequent trials (from 6 to 30 h after treatment). Values for U crit and EMG were not significantly different from the control group in any of the trials conducted 1–30 h after treatment. We concluded that chum salmon had regained their normal swimming ability by 6 h after treatment and could be safely released into the natural environment.  相似文献   
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The effectiveness of the incorporation of genomic pre‐selection into dairy cattle progeny testing (GS‐PT) was compared with that of progeny testing (PT) where the fraction of dam to breed bull (DB) selected was 0.01. When the fraction of sires to breed bulls (SB) selected without being progeny tested to produce young bulls (YB) in the next generation was 0.2, the annual genetic gain from GS‐PT was 13% to 43% greater when h2 = 0.3 and 16% to 53% greater when h2 = 0.1 compared with that from PT. Given h2 = 0.3, a selection accuracy of 0.8 for both YB and DB, and selected fractions of 0.117 for YB and 0.04 for DB, GS‐PT produced 40% to 43% greater annual genetic gain than PT. Given h2 = 0.1, a selection accuracy of 0.6 for both YB and DB, and selected fractions of 0.117 for YB and 0.04 for DB, annual genetic gain from GS‐PT was 48% to 53% greater than that from PT. When h2 = 0.3, progeny testing capacity had little effect on annual genetic gain from GS‐PT. However, when h2 = 0.1, annual genetic gain from GS‐PT increased with increasing progeny testing capacity.  相似文献   
46.
Fog chemistry was studied for four years (April 1997–March 2001) at Mt. Rokko (altitude 931 m) in Kobe, Japan. A collection of samples was obtained at a mountainous site close to a highly industrialized area. The samples were collected by an active string-fog collector. The summer fog was dense and frequent. The geography of Mt. Rokko is linked to the seasonality of the occurrence and the thickness of the fog. Among the meteorological parameters, the relative humidity was important for the occurrence of fog. The correlation of the concentrations of the components in fog water indicated that (NH4)2SO4 and/or NH4HSO4 were involved in the process of the formation of fog drops in the atmosphere. The concentration of the components decreased with an increase in the liquid water content (LWC) of the fog, and the seasonal variation of the concentration of some components depended on the seasonal variation of the LWC. The equivalent ratio of NO3 ? to non-sea salt (nss?) SO4 2? was considerably larger than that in precipitation. Ammonium ion accounted for the largest percentage of cations, which indicates that NH4 + was an important counter cation for NO3 ? and nss-SO4 2?. A unique fog event in which the air pollutants seemed to be scavenged stoichiometrically was sometimes observed. The methodology used for collecting fog water at 60 mL intervals provided detailed information.  相似文献   
47.
Water, Air, &; Soil Pollution - A monitoring network for acid deposition that consisted of five sites in Hyogo, Japan, and covered a region of about 100 km × 100 km revealed the spatial...  相似文献   
48.
Cloud water deposition to canopies of Cryptomeria japonica at Mt.Rokko, Kobe, Japan, was estimated from throughfall measurements and fog water collections carried out during a full year. Annual cloud frequency was 11.5–15.5% and liquid water content (LWC) was 0.059 g/m3. Since cloud water deposition on to forest canopies was significantly correlated with the amount of fog water collected, the former parameter could be quantitatively derived from throughfall measurements. Annual cloud water deposition on to Cryptomeria canopies was 1420–2860 mm (Av. 2140 mm), corresponding to 90–180% (Av. 122%) of annual rainfall. The rate of deposition was higher at the mountain ridge and the forest edge than at the mountain side and the forest interior. Annual deposition of SO4 2?, NO3 ?, H+ and NH4 + from cloud water was estimated as 204, 153, 2.5 and 58 kg/ha, respectively, equivalent to 5.8–11.7 times the corresponding deposition via rain. The values are equal to, or exceed, the maximum deposition reported for Appalachian forests in the eastern United States. Multiple regression analyses indicate that cloud water deposition on to Cryptomeria canopies was significantly correlated with the following three parameters: cloud frequency, LWC, and wind speed. Thus, these three factors apparently control cloud water deposition on to forest canopies.  相似文献   
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A simulation analysis and real phenotype analysis were performed to evaluate the impact of three different relationship matrices on heritability estimation and prediction accuracy in a closed‐line breeding of Duroc pigs. The numerator relationship matrix (NRM), single nucleotide polymorphism (SNP)‐based genomic relationship matrix (GRM) (GS), and haplotype‐based GRM (GH) were applied in this study. We used PorcineSNP60 genotype array data (38 114 SNPs) of 831 Duroc pigs with four selection traits. In both heritability estimation and prediction accuracy, the accuracy depended on the number of animals with records. For heritability estimation, a large difference in the results among three relationship matrices was not shown, but the trend of the estimated heritabilities between GRMs, that is GS < GH, was shown in this population. For the accuracy of prediction values in test animals, the accuracies of prediction values obtained by two GRMs were higher than that by the NRM in this population. The accuracies obtained by GRMs using animals with no records were lower than that by the NRM using animals with their performance records, but were close to that by the NRM using animals with full‐sib testing records.  相似文献   
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