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121.
The late-spring quantitative relationship between epiphyton and macroinvertebrates was analyzed on the basis of units of colonizable plant surface of Typha angustifolia, Phragmites australis and Nuphar lutea (floating leaves) in the shallow euthrophic Lake Loosdrecht (the Netherlands), with a high seston load. The non-predatory chironomid larvae (Glyptotendipes viridis, Endochironomus albipennis, Pentapedilum sordens, Cricotopus sylvestris agg.) dominated among the macroinvertebrate taxa, controlling the diversity and resemblance of macroinvertebrate assemblages. There was a gradient in functional feeding groups among the chironomids from continuous filtering of the seston to prevailing utilization of epiphyton. We found no direct relationship between the total macroinvertebrate abundance and the epiphyton mass on the plants surface. We attribute this to the filter feeding-strategy of the most abundant species, Glyptotendipes viridis, that utilizes seston in the eutrophicated lake. 相似文献
122.
N. Hayashi H. Seino K. Irie M. Watanabe K. L. Clark K. Matsumoto T. Nishimoto 《Molecular & general genetics : MGG》1996,253(1-2):149-156
The Saccharomyces cerevisiae temperature-sensitive mutants srm1-1, mtr1-2 and prp20-1 carry alleles of a gene encoding a homolog of mammalian RCC1. In order to identify a protein interacting with RCC1, a series
of suppressors of the srm1-1 mutation were isolated as cold-sensitive mutants and one of the mutants, designated ded1-21, was found to be defective in the DED1 gene. The double mutant, srm1-1 ded1-21, could grow at 35° C, but not at 37° C. A revertant of srm1-1 ded1-21 that became able to grow at 37° C acquired another mutation in the SRM1 gene, indicating the tight relationship between SRM1 and DED1. In all the rcc1
- strains examined, the amount of mutated SRM1 proteins was reduced or not detectable at the nonpermissive temperature. While
mutated SRM1 protein was stabilized in all of the rcc1
- strains by the ded1-21 mutation, the ded1-21 mutation suppressed both srm1-1 and mtr1-2, but not the prp20-1 mutation, contrary to the previous finding that overproduction of the S. cerevisiae Ran homolog GSP1 suppresses prp20-1, but not srm1-1 or mtr1-2.
Received: 20 March 1996/Accepted: 1 July 1996 相似文献
123.
A stable Escherichia coli-mycobacteria shuttle vector 'pSO246' in Mycobacterium bovis BCG 总被引:1,自引:0,他引:1
Sohkichi Matsumoto Mikio Tamaki Hideharu Yukitake Takemitu Matsuo Manko Naito Hiroshi Teraoka Takeshi Yamada 《FEMS microbiology letters》1996,135(2-3):237-243
Abstract The most widely used plasmid vector system in mycobacteria is based on pAL5000 from Mycobacterium fortuitum . The derivatives of the pAL5000-based shuttle vectors between Escherichia coli and mycobacteria, which we have utilized to secrete recombinant antigens, were generated. The stability of the vectors was assessed in Mycobacterium bovis BCG (BCG). The plasmid vector pSO246 was stable in BCG for at least 50 generations. 相似文献
124.
Tomokazu Indoh Sachiko Shirakawa Tohru Kubota Teruo Yashiki Emiko Isogai Nobuhiro Fujii 《Microbiology and immunology》1996,40(9):675-679
Persistent infections with mumps virus were established in several human lymphoid cells of T-cell origin (Molt-4, TALL-1, and CCRF-CEM) and human monocyte cells (U937 and THP-1). 2′,5′-Oligoadenylate synthetase (2–5AS) activity was demonstrated to be only slightly induced by interferon (IFN) or TPA (12-O-tetradecanoyl-phorbol-13-acetate) treatment in these cells. Treatment of the persistently infected cells with IFN or TPA did not stimulate an increase in the amount of synthetase mRNA. Induction of cell differentiation and augmentation of IFN production by TPA were demonstrated in U937 cells persistently infected with mumps virus (U937-MP). Similar results for IFN production were obtained from differentiated U937 cells. It is suggested that cell differentiation of U937 cells might be associated with the development of IFN inducibility. 相似文献
125.
126.
Haruko Ogawa Ako Hijikata Maho Amano Kyoko Kojima Hisako Fukushima Ineo Ishizuka Yoshie Kurihara Isamu Matsumoto 《Glycoconjugate journal》1996,13(4):555-566
The oligosaccharide structures ofCry j I, a major allergenic glycoprotein ofCryptomeria japonica (Japanese cedar, sugi), were analysed by 400 MHz1H-NMR and two-dimensional sugar mapping analyses. The four major fractions comprised a series of biantennary complex type N-linked oligosaccharides that share a fucose/xylose-containing core and glucosamine branches including a novel structure with a nongalactosylated fucosylglucosamine branch.Rabbit polyclonal anti-Cry j I IgG antibodies cross-reacted with three different plant glycoproteins having the same or shorter N-linked oligosaccharides asCry j I. ELISA and ELISA inhibition studies with intact glycoproteins, glycopeptides and peptides indicated that both anti-Cry j I IgGs and anti-Sophora japonica bark lectin II (B-SJA-II) IgGs included oligosaccharide-specific antibodies with different specificities, and that the epitopic structures against anti-Cry j I IgGs include a branch containing 1–6 linked fucose and a core containing fucose/xylose, while those against anti-B-SJA-II IgGs include nonreducing terminal mannose residues. The cross-reactivities of human allergic sera to miraculin andClerodendron Trichotomum lectin (CTA) were low, and inhibition studies suggested that the oligosaccharides onCry j I contribute little or only conformationally to the reactivity of specific IgE antibodies.Abbreviations
Cry j I
a major allergenic glycoprotein ofCryptomeria japonica
- B-SJA-II
Sophora japonica bark lectin II
- CTA
Clerodendron trichotomum lectin
- TFMS
trifluoromethanesulfonic acid
- HRP
horseradish peroxidase 相似文献
127.
Effects of 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS) on carnation flower longevity 总被引:2,自引:0,他引:2
Naoki Midoh Yuki Saijou Kuniomi Matsumoto Michiaki Iwata 《Plant Growth Regulation》1996,20(3):195-199
The effects of a novel preservative for cut carnation flowers, 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS), were investigated. DPSS extended the vase life of cut carnation flowers not only by continuous treatment but pulse treatment as well. This inhibition of senescence by DPSS appeared to depend on that of ethylene production in carnation flowers. DPSS provided no protection from the action of ethylene nor did it inhibit 1-aminocyclopropane-1-carboxylic acid (ACC) synthase. It did inhibit ACC-dependent ethylene production in carnation petal discs, suggesting possible potential for inhibiting ACC oxidase. 相似文献
128.
To clarify the mechanism of aluminum (Al) toxicity and Al tolerance, we isolated a new clone (pAL201) from a tobacco cDNA library. Northern blot hybridization analysis indicated that the expression of pAL201 is induced by Al treatment and phosphate (P1 ) starvation. The complete cDNA sequence suggested that this clone encodes a moderately anionic peroxidase (EC 1.11.1.7). Analysis by isoelectric focussing indicated that a moderately anionic peroxidase (approximately pI 6.7) and two cationic peroxidases (pI 9.2 and 9.7) in the soluble fraction are activated by Al treatment and P1 starvation, while two moderately anionic isozymes are repressed by these stresses. We suppose that Al ion stress can control the activity of some peroxidase isozymes, one of which is probably induced by enhanced gene expression of pAL201. There is a possibility that some of these isozymes have some functions in Al ion stress. 相似文献
129.
Kato Ryoichi; Takatsuna Sachiko; Wada Tsuyoshi; Narihara Yumi; Suzuki Takashi 《Plant & cell physiology》1996,37(5):667-672
Five-mm sections of elongation zones of Zea mesocotyls wereincubated for designated periods with various concentrationsof IAA. In vitro protein phosphorylation in the soluble fraction(85,000 x g supernatant) prepared from the sections was analyzedby sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The phosphorylation of proteins in the soluble fraction thathad been prepared from sections incubated for 20 min in thepresence of 10{small tilde}s M IAA was greater than that inthe sections incubated for 20 min without IAA. The amount ofphosphorylation of proteins per protein became higher when higherconcentrations increased (10{small tilde}810{small tilde}5M).The growth of sections incubated in the presence of 10{smalltilde}8 M IAA or higher concentrations was greater than thatof sections incubated in the absence of IAA. The promotion ofgrowth by IAA was greater at higher concentrations of IAA. Proteinsin the soluble fraction, prepared from sections incubated for20 min in the presence of 10{small tilde}5 M IAA, were phosphorylatedin the presence of either 10 fM cAMP, 10 µM cGMP, 100µM W-7, 100 µM W-5, 20 µM H-7 or 20 µMHA1004. The calmodulin antagonist, W-7, and the inhibitor ofprotein kinase C, H-7, inhibited the phosphorylation of proteinsstimulated by incubation with IAA. These results suggest thatIAA promotes cell elongation via protein phosphorylation thatdepends on calmodulin-dependent protein kinase and protein kinaseC. (Received November 29, 1995; Accepted May 20, 1996) 相似文献
130.
Expression of NADH-Dependent Glutamate Synthase in Response to the Supply of Nitrogen in Rice Cells in Suspension Culture 总被引:2,自引:0,他引:2
Watanabe Sachiko; Sakai Takahiro; Goto Satoshi; Yaginuma Toshiko; Hayakawa Toshihiko; Yamaya Tomoyuki 《Plant & cell physiology》1996,37(7):1034-1037
The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected.
1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan. 相似文献