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21.
Samuiddin Syed Ramesh Rajpurohit Sangduk Kim Woon Ki Paik 《Journal of Protein Chemistry》1992,11(3):239-246
We have earlier identified and purified two protein-lysine N-methyltransferases (Protein methylase III) fromEuglena gracilis [J. Biol. Chem.,260, 7114 (1985)]. The enzymes were highly specific toward histone H1 (lysine-rich), and the enzymatic products were identified as -N-mono-, di- and trimethyllysines. These earlier studies, however, were carried out with rat liver histone H1 as thein vitro substrate. Presently, histone H1 has been purified fromEuglena gracilis through Bio-Rex 70 and Bio-Gel P-100 column chromatography. TheEuglena histone H1 showed a single band on SDS-polyacrylamide gel electrophoresis and behaved like other histone H1 of higher animals, whereas it had a much higherR
f value than the other histones H1 in acid/urea gel electrophoresis. When theEuglena histone H1 was [methyl-3H]-labeledin vitro by a homologous enzyme (one of the twoEuglena protein methylase III) and analyzed on two-dimensional gel electrophoresis, three distinctive subtypes of histone H1 were shown to be radiolabeled, whereas five subtypes of rat liver histone H1 were found to be labeled. Finally, by the combined use of a strong cation exchange and reversed-phase Resolve C18 columns on HPLC, we demonstrated thatEuglena histone H1 contains approximately 9 mol% of -N-methyllysines (1.40, 1.66, and 5.62 mol% for -N-mono-, di- and trimethyllysines, respectively). This is the first demonstration of the natural occurrence of -N-methyllysines in histone H1. 相似文献
22.
Due to resource scarcity and environmental degradation, a new development concept emphasizing environmental concerns, called the circular economy (CE), has been enacted in legislation in China. This environmental management concept can be implemented at three levels, namely, region, industrial zone, and individual enterprise, with the objective of boosting economic development while lessening environmental and resource challenges. Environmental supply chain cooperation (ESCC), an approach that utilizes customer and supplier cooperation in environmental management, has been initiated among Chinese enterprises. Using survey data collected from 396 Chinese manufacturers, we examine the role of ESCC practices in influencing the relationship between implementing CE practices and the achievement of performance outcomes by testing the moderation and mediation effects of ESCC practices on the CE practice‐performance relationship through hierarchical regression analysis. Our data analyses indicate that ESCC practices are useful by moderation and, in some cases, essential by mediation, for Chinese manufacturers seeking to realize the performance targets desired in CE practices. The results highlight the need for Chinese manufacturers to improve supply chain coordination in their implementation of CE. On the policy side, our research findings suggest that ESCC practices are beneficial and, in some cases, necessary for the development of CE in China. 相似文献
23.
Suk Young Oh Chun Hua Wu Elena Popova Eun Joo Hahn Kee Yoeup Paek 《Journal of Plant Biology》2009,52(4):348-354
We tested desiccation and/or vitrification procedures to cryopreserve the adventitious roots of Panax ginseng, the source of commercially produced ginsenosides. When only desiccation was applied, the post-freeze survival of 3- to 4-mm
root tips was <14% regardless of the composition of the preculture medium or the explant origin. Callus formation was frequently
observed after cryopreservation. In contrast, 90% survival and 32.5% root formation efficiency were achieved after cryopreservation
when a vitrification protocol was followed. Adventitious root cultures in flasks and bioreactors were reestablished from root
tips cryopreserved by vitrification. A prolonged lag-phase and lower biomass production were recorded in post-freeze-regenerated
cultures compared with control roots that were subcultured four times in flasks. However, biomass accumulations did not differ
between control and regenerated roots at the end of the sixth subculturing period. After 40 days of culture in bioreactors,
a mean value of 12.5 g dw L−1 was recorded for post-freeze-regenerated cultures versus 9.1 g dw L−1 for the control roots. Production of triol and diol ginsenosides in our bioreactor cultures also was enhanced after cryopreservation,
by 41.0% and 89.8%, respectively. These results suggest that the vitrification method is successful for cryopreservation of
P. ginseng adventitious roots. 相似文献
24.
Akt-mediated phosphorylation of the G protein-coupled receptor EDG-1 is required for endothelial cell chemotaxis 总被引:7,自引:0,他引:7
Lee MJ Thangada S Paik JH Sapkota GP Ancellin N Chae SS Wu M Morales-Ruiz M Sessa WC Alessi DR Hla T 《Molecular cell》2001,8(3):693-704
The role of the protein kinase Akt in cell migration is incompletely understood. Here we show that sphingosine-1-phosphate (S1P)-induced endothelial cell migration requires the Akt-mediated phosphorylation of the G protein-coupled receptor (GPCR) EDG-1. Activated Akt binds to EDG-1 and phosphorylates the third intracellular loop at the T(236) residue. Transactivation of EDG-1 by Akt is not required for G(i)-dependent signaling but is indispensable for Rac activation, cortical actin assembly, and chemotaxis. Indeed, T236AEDG-1 mutant sequestered Akt and acted as a dominant-negative GPCR to inhibit S1P-induced Rac activation, chemotaxis, and angiogenesis. Transactivation of GPCRs by Akt may constitute a specificity switch to integrate rapid G protein-dependent signals into long-term cellular phenomena such as cell migration. 相似文献
25.
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27.
Production of nattokinase by high cell density fed-batch culture of Bacillus subtilis 总被引:1,自引:0,他引:1
Bacillus subtilis was cultivated to high cell density for nattokinase production by pH-stat fed-batch culture. A concentrated mixture solution
of glucose and peptone was automatically added by acid-supplying pump when culture pH rose above high limit. Effect of the
ratio of glucose to peptone in feeding solution was investigated on cell growth and nattokinase production by changing the
ratio from 0.2 to 5 g glucose/g peptone. The highest cell concentration was 77 g/L when the ratio was 0.2 g glucose/g peptone.
Cell concentration decreased with increasing the ratio of glucose to peptone in feeding solution, while the optimum condition
existed for nattokinase production. The highest nattokinase activity was 14,500 unit/mL at a ratio of 0.33 g glucose/g peptone,
which was 4.3 times higher than that in batch culture. 相似文献
28.
Hyung Soo Park Byung Hong Kim Hyo Suk Kim Hyung Joo Kim Gwang Tae Kim Mia Kim In Seop Chang Yong Keun Park Hyo Ihl Chang 《Anaerobe》2001,7(6):297
An obligatory anaerobic bacterium was isolated from a mediator-less microbial fuel cell using starch processing wastewater as the fuel and designated as EG3. The isolate was Gram-positive, motile and rod (2.8–3.0 μm long, 0.5–0.6 μm wide). The partial 16S rRNA gene sequence and analysis of the cellular fatty acids profile suggested that EG3 clusters with Clostridium sub-phylum and exhibited the highest similarity (98%) with Clostridium butyricum. The temperature and pH optimum for growth were 37°C and 7.0, respectively. The major products of glucose and glucose/Fe(O)OH metabolism were lactate, formate, butyrate, acetate, CO2and H2. Growth was faster at the initial phase and the cell yield was higher when the medium was supplemented with Fe(O)OH than without Fe(O)OH. These results suggest that Fe(III) ion is utilised as an electron sink. Cyclic voltammetry showed that Clostridium butyricum EG3 cells were electrochemically active. It is a novel characteristic of strict anaerobic Gram-positive bacteria. 相似文献
29.
Won Yu Jung Kang Lae Hyung Lee Ah Ra Paik Bomina Kim Hyun Lee Sung Geun Park Seung Won Hong Seung Jin Paik Soon Young 《Journal of microbiology (Seoul, Korea)》2020,58(5):422-429
Journal of Microbiology - Enterovirus A71 (EV71), the main etiological agent of handfoot- mouth disease (HFMD), circulates in many areas of the world and has caused large epidemics since 1997,... 相似文献