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Nucleotide sequences of the small-subunit (SSU) ribosomal DNA were determined forPelvetia babingtonii, P. canaliculate, Pelvetiopsis limitata, andAscophyllum nodosum in the family Fucaceae. A total of 1755 positions were aligned for the whole sequence. The positional differences in the
primary structure among the taxa ranged from 16 to 30 nucleotide changes in pairwise comparisons. There was a minimum divergence
betweenPs. limitata andP. babingtonii while a maximum betweenPs. limitata andP. canaliculata. The SSU rDNA trees showed that the genusPelvetia was not monophyletic and the genusPelvetiopsis was not closely related toPelvetia. Our results suggest that the taxonomic revision of the genusPelvetia as well as the family Fucaceae is needed based on detailed morphological observations. 相似文献
3.
East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided. 相似文献
4.
Menyanthes trifoliata is a threatened and endangered species in Korea and USA. To assess the important ecological characteristics for its conservation
and restoration, we measured the level of soluble reactive phosphorus (SRP) in the water, total N and C contents in the plants,
and the water-holding capacity of the surrounding floating peat mat. These factors, which limit the success of aquatic macrophytes,
were examined for their effects on the growth of this species. Leaflet areas and petiole lengths ranged from 6.1 cm2 and 12.4 cm, respectively, at a water depth of 5 cm, to 22.7 cm2 and 33.0 cm, respectively, at 40 cm. The peat mat was able to retain water at a depth of 5 to 45 cm. SRPs ranged from 10
to 46 ppb, while total C and N contents were between 0.62% (petiole) and 2.76% (leaf), and between 39.7% (petiole) and 43.8%
(stem), respectively. The water-holding level was not correlated with SRP, and neither phosphorus nor nitrogen content affected
plant growth. However, the capacity of the floating mat to hold water as the depth subsided was positively related to growth.
This suggests that such mats are good tools for restoring populations ofM. trifoliata when materials with high water-holding capacities are used. 相似文献
5.
Surface Plasmon Resonance Imaging-Based Protein Array Chip System for Monitoring a Hexahistidine-Tagged Protein during Expression and Purification 下载免费PDF全文
Hyeon-Su Ro Sun Ok Jung Byung Hoon Kho Hyung Pyo Hong Jae Sung Lee Yong-Beom Shin Min Gon Kim Bong Hyun Chung 《Applied microbiology》2005,71(2):1089-1092
A surface plasmon resonance imaging-based Ni2+-iminodiacetic acid-coated gold chip system was developed to enable specific detection of a hexahistidine-tagged recombinant protein in crude extracts or in column chromatography fractions. This system is especially advantageous for high-throughput analysis of multiple proteins. 相似文献
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Won Jae Choi 《Applied microbiology and biotechnology》2009,84(2):239-247
Enantiopure epoxides are high value-added synthons for the production of pharmaceuticals, agrochemicals, as well as versatile
fine chemicals and have broad scope of market demand for their applications. A major challenge in conventional organic synthesis
is to generate such compounds in high enantiopurity with reasonable yield. Among possible chemical and biological technologies
for enantiopure epoxide preparation, enzymatic kinetic resolution has been paid much attention with respect to its high enantioselectivity.
Epoxide hydrolase (EH) has shown promising characteristics for the preparation of enantiopure epoxides and vicinal diols during
enantioselective hydrolysis of racemic epoxides. EH is readily available from microbial resources thus it is being employed
for biohydrolysis of a variety of epoxides. Recent technical progress in EH-catalyzed enantioselective hydrolysis is summarized
in terms of exploration of novel EH, its functional improvement, high throughput assay, and preparative scale resolution process. 相似文献
9.
Robin F. MORALES Ki Moon SEONG Cha Soon KIM Young-Woo JIN Kyung-Jin MIN 《Entomological Research》2010,40(4):225-228
It is well known that music can have calming effects on humans, other mammals and birds. Reducing environmental stress or enhancing the resistance to certain stressors has been shown to extend lifespan in several organisms. Evidence also suggests that mild temporary stress may also enhance stress resistance and ultimately slow the aging process. This study explored the possibility that music may influence the lifespan of the fruit fly Drosophila melanogaster, possibly by affecting responses to stress. Flies received either background sounds (control), or background sounds supplemented with music (experimental). The experimental group had classical music playing constantly at an average of 20 dB above background sound. The median lifespan of females receiving music was 42 days compared to the median of 45 days without music, but the difference was not significant. For males median lifespans were 42 days with music exposure, and 47 days without music and the difference was significant. These results suggest that exposure to classical music decreased the lifespan of male Drosophila. Both experimental and control populations showed age-dependent increases in mortality, indicating that music affects the normal aging process rather than showing overt toxicity. These results suggest that certain auditory stimuli may be stressful and can be used as insect management. 相似文献
10.
Secretion of Recombinant Pediocin PA-1 by Bifidobacterium longum, Using the Signal Sequence for Bifidobacterial α-Amylase 下载免费PDF全文
Gi-Seong Moon Yu-Ryang Pyun Myeong Soo Park Geun Eog Ji Wang June Kim 《Applied microbiology》2005,71(9):5630-5632
A recombinant DNA, encoding the chimeric protein of the signal sequence for bifidobacterial α-amylase mature pediocin PA-1, was introduced into Bifidobacterium longum MG1. Biologically active pediocin PA-1 was successfully secreted from the strain and showed bactericidal activity against Listeria monocytogenes and the same molecular mass as native pediocin PA-1. 相似文献