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991.
Kim D Kim SN Baik KS Park SC Lim CH Kim JO Shin TS Oh MJ Seong CN 《Journal of microbiology (Seoul, Korea)》2011,49(1):141-145
A metagenomic fosmid library was constructed using genomic DNA isolated from abalone intestine. Screening of a library of
3,840 clones revealed a 36 kb insert of a cellulase positive clone (pAMHElO). A shotgun clone library was constructed using
the positive clone (pAMHElO) and further screening of 3,840 shotgun clones with an approximately 5 kb insert size using a
Congo red overlay revealed only one cellulase positive clone (pAMHL9). The pAMHL9 consisted of a 5,293-bp DNA sequence and
three open reading frames (ORFs). Among the three ORFs, cellulase activity was only shown in the recombinant protein (CelAMll)
coded by ORF3, which showed 100% identity with outer membrane protein A from Vibrio alginolyticus 12G01, but no significant sequence homology to known cellulases. The expressed protein (CelAMll) has a molecular weight of
approximately 37 kDa and the highest CMC hydrolysis activity was observed at pH 7.0 and 37°C. The carboxymethyl cellulase
activity was determined by zymogram active staining and different degraded product profiles for CelAMll were obtained when
cellotetraose and cellopentaose were used as the substrates, while no substrate hydrolysis was observed on oligosaccharides
such as cellobiose and cellotriose. 相似文献
992.
In this study, cephalosporin C production by Acremonium chrysogenum M35 cultured with crude glycerol instead of rice oil and methionine was investigated. The addition of crude glycerol increased
cephalosporin C production by 6-fold in shake-flask culture, and also the amount of cysteine. In fed-batch culture without
methionine, crude glycerol resulted only in overall improvement in cephalosporin C production (about 700%). In addition, A. chrysogenum M35 became highly differentiated in fed-batch culture with crude glycerol, compared with the differentiation in batch culture.
The results presented here suggest that crude glycerol can replace methionine and plant oil as cysteine and carbon sources
during cephalosporin C production by A. chrysogenum M35. 相似文献
993.
994.
Hwan-Seok Choi Geun-Joong Kim Hyun-Jae Shin 《Biotechnology and Bioprocess Engineering》2011,16(1):153-157
Many moth pheromones and synthetic attractants have been used to monitor or decrease pest populations. However, due to their
low economic efficiencies and narrow target specificities these methods are of limited use for trapping pests in large agricultural
fields. In an effort to address this problem, we selected oak (Quercus serrata) sawdust media fermented by the yeast strain Pichia anomala, and examined its ability to attract lepidopteran moth pests for mass trapping in an apple (Malus domestica) orchard. A total of 57 taxa were trapped, including 42 species of lepidopteran pests. The most frequently caught lepidopteran
pests included Adoxophyes orana (40.0 ± 3.5 individuals/trap/week), Oraesia excavata (35.5 ± 2.5), and Adris tyrannus amurensis (35.5 ± 2.5). Notably, less fruit damage was recorded in the experimental orchard versus a trap-free neighboring control
orchard. These results suggest that adult moths might be effectively attracted and mass captured using P. anomala-fermented oak sawdust media as bait. 相似文献
995.
Shin‐ya OHBA 《Entomological Science》2011,14(3):364-365
The giant water bug, subfamily Lethocerinae, which has the largest body size among Belostomatidae, is known to be a vertebrate specialist that preys upon fish, amphibians and snakes. However, there have been no reports concerning predation on a turtle by Lethocerinae. Here, I report that a male giant water bug Kirkaldyia (Lethocerus) deyrolli (Heteroptera: Belostomatidae) (58.09 mm in total length) was catching hold of a turtle Chinemys reevesii (34.14 mm in carapace length) in a ditch adjoining a paddy rice field. This is a first report of K. deyrolli eating a turtle. 相似文献
996.
Takashi Sayama Tae-Young Hwang Kunihiko Komatsu Yoshitake Takada Masakazu Takahashi Shin Kato Hiroko Sasama Ayako Higashi Yumi Nakamoto Hideyuki Funatsuki Masao Ishimoto 《DNA research》2011,18(2):107-115
Among commonly applied molecular markers, simple sequence repeats (SSRs, or microsatellites) possess advantages such as a high level of polymorphism and codominant pattern of inheritance at individual loci. To facilitate systematic and rapid genetic mapping in soybean, we designed a genotyping panel comprised 304 SSR markers selected for allelic diversity and chromosomal location so as to provide wide coverage. Most primer pairs for the markers in the panel were redesigned to yield amplicons of 80–600 bp in multiplex polymerase chain reaction (PCR) and fluorescence-based sequencer analysis, and they were labelled with one of four different fluorescent dyes. Multiplex PCR with sets of six to eight primer pairs per reaction generated allelic data for 283 of the 304 SSR loci in three different mapping populations, with the loci mapping to the same positions as previously determined. Four SSRs on each chromosome were analysed for allelic diversity in 87 diverse soybean germplasms with four-plex PCR. These 80 loci showed an average allele number and polymorphic information content value of 14.8 and 0.78, respectively. The high level of polymorphism, ease of analysis, and high accuracy of the SSR genotyping panel should render it widely applicable to soybean genetics and breeding. 相似文献
997.
Mi Seon Park Hyun Suk Shin Gyung-Suk Kil Jehee Lee Cheol Young Choi 《Ichthyological Research》2011,58(3):195-201
We examined changes in the expression of Na+/K+-ATPase mRNA in the gills of the cinnamon clownfish using quantitative real-time PCR in an osmotically changing environment
[seawater (35 psu; practical salinity unit, 1 psu ≈ 1‰) → brackish water (17.5 psu) and brackish water with prolactin]. The
expression of Na+/K+-ATPase mRNA in gills was increased after the transfer to brackish water, and the expression was repressed by prolactin treatment.
Also, activities of gill Na+/K+-ATPase and plasma cortisol levels increased after the transfer to brackish water and were repressed in brackish water with
prolactin treatment. Na+/K+-ATPase-immunoreactive cells were almost consistently observed in the gill filaments, but absent from the lamella epithelia.
The plasma osmolality level decreased in brackish water, but the level of this parameter increased in brackish water with
prolactin treatment during salinity change. These results suggest that the Na+/K+-ATPase gene plays an important role in osmoregulation in gills, and prolactin improves the hyperosmoregulatory ability of
cinnamon clownfish in a brackish water (hypoosmotic) environment. 相似文献
998.
Sato K Watanabe T Wang S Kakeno M Matsuzawa K Matsui T Yokoi K Murase K Sugiyama I Ozawa M Kaibuchi K 《Molecular biology of the cell》2011,22(17):3103-3119
Cadherin trafficking controls tissue morphogenesis and cell polarity. The endocytic adaptor Numb participates in apicobasal polarity by acting on intercellular adhesions in epithelial cells. However, it remains largely unknown how Numb controls cadherin-based adhesion. Here, we found that Numb directly interacted with p120 catenin (p120), which is known to interact with E-cadherin and prevent its internalization. Numb accumulated at intercellular adhesion sites and the apical membrane in epithelial cells. Depletion of Numb impaired E-cadherin internalization, whereas depletion of p120 accelerated internalization. Expression of the Numb-binding fragment of p120 inhibited E-cadherin internalization in a dominant-negative fashion, indicating that Numb interacts with the E-cadherin/p120 complex and promotes E-cadherin endocytosis. Impairment of Numb induced mislocalization of E-cadherin from the lateral membrane to the apical membrane. Atypical protein kinase C (aPKC), a member of the PAR complex, phosphorylated Numb and inhibited its association with p120 and α-adaptin. Depletion or inhibition of aPKC accelerated E-cadherin internalization. Wild-type Numb restored E-cadherin internalization in the Numb-depleted cells, whereas a phosphomimetic mutant or a mutant with defective α-adaptin-binding ability did not restore the internalization. Thus, we propose that aPKC phosphorylates Numb to prevent its binding to p120 and α-adaptin, thereby attenuating E-cadherin endocytosis to maintain apicobasal polarity. 相似文献
999.
1000.
E-Hyun Shin Chan Park Hyun kyung Kim Dong-Kyu Lee Soon-Il Kim Hyesook Kang Kyu-Sik Chang 《Journal of Asia》2011,14(3):233-236
Field-collected populations of mayflies, Ephemera orientalis were tested for susceptibility to 10 different insecticides using a direct-contact mortality bioassay. Ephemera orientalis subimagoes were susceptible to the insecticides chlorpyrifos, fenitrothion and chlorfenapyr with LD50 values of 69.7, 78.8 and 81.9 μg/♀, and adults had LD50 values of 71.9, 78.8 and 85.4 μg/♀, respectively. Susceptibility ratios (SRs) of subimagoes and adults of E. orientalis to the 10 insecticides were 1.0 to1.2 folds. The mayflies showed higher susceptibility to organophosphates than to pyrethroids. The SRs of Anopheles sinensis to E. orientalis were 514 to 1438 folds higher for organophosphates (LD50 values of 0.05 to 0.23 μg/♀) and 62 to 1155 folds higher for pyrethroids (LD50 values of 0.13 to 2.41 μg/♀). The SRs of Culex pipiens to E. orientalis were 606 to 3595 folds higher for organophosphates with LD50 values of 0.02–0.17 μg/♀ and 81 to 1365 folds higher for pyrethroids with LD50 values of 0.11–1.83 μg/♀. These results indicate that the use of ineffective insecticides will result in unsatisfactory control against field populations of the subimagoes and adults of E. orientalis. 相似文献