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1.
In Saccharomyces cerevisiae, we synthesized and secreted L-HBVsAg (named as pre-S(Met1 to Asn174)::S(Met175 to Ile400)) and three mutants, i.e., pre-S degree degree::S (Asn15Gln and Asn123Gln), pre-S degree degree::S degree (Asn15Gln, Asn123Gln, and Asn320Gln), and pre-S degree degree::S degree degree (Asn15Gln, Asn123Gln, Asn233Gln, and Asn320Gln). All of the secreted pre-S::S was N-glycosylated, i.e., hyper-mannosylated. In the secretion of pre-S degree degree::S and pre-S degree degree::S degree, besides the hyper-mannosylated form, another immunoreactive protein with much lower molecular mass was observed, which seems to be unglycosylated form of pre-S degree degree::S and pre-S degree degree::S degree. Only a part of the secreted pre-S degree degree::S or pre-S degree degree::S degree molecules was N-glycosylated, and the site for the partial N-glycosylation seems to be Asn233 in S-antigen region. Compared to the N-glycosylated pre-S degree degree::S and pre-S degree degree::S degree, pre-S degree degree::S degree degree (non-N-glycosylated mutant) was secreted with lower secretion efficiency but showed apparent immunoreactivity to anti-S antigen monoclonal Ab. Interestingly, unlike pre-S degree degree::S degree degree with authentic C-terminus, the recombinant pre-S degree degree::S degree degree with C-terminal myc or poly-histidine tag (pre-S degree degree::S degree degree::tag) was almost all aggregated into insoluble proteins in the intracellular region. Conclusively, the C-terminal sequence and glycosylation in S-antigen region seem to be of crucial importance in determining the secretion efficiency of L-HBVsAg in S. cerevisiae.  相似文献   

2.
Species boundaries were assessed by phenetic analyses of morphological data for all species of wild potatoes (SOLANUM: section PETOTA:) assigned to ser. LONGIPEDICELLATA: S. fendleri, S. hjertingii, S. matehualae, S. papita, S. polytrichon, and S. stoloniferum. These six tetraploid species grow in the southeastern United States (S. fendleri) and Mexico (all six species). We also analyzed morphologically similar species in ser. DEMISSA: (S. demissum) and ser. TUBEROSA: (S. avilesii, S. gourlayi, S. verrucosum). We chose S. verrucosum and S. demissum as Mexican representatives, and S. avilesii and S. gourlayi as South American representatives of other series that are difficult to distinguish from ser. LONGIPEDICELLATA: We also analyzed morphologically more dissimilar species in ser. TUBEROSA: (S. berthaultii) and ser. YUNGASENSIA: (S. chacoense). The results support only three species in ser. LONGIPEDICELLATA: (1) S. polytrichon, (2) S. hjertingii + S. matehualae, (3) S. fendleri + S. papita + S. stoloniferum. Solanum avilesii, S. gourlayi, and to a lesser extent S. demissum and S. verrucosum are very similar to members of ser. LONGIPEDICELLATA: and are difficult to distinguish practically from them, despite differences in chromosome numbers and crossability relationships. These data help document and explain the extensive taxonomic difficulty in sect. Petota, highlight conflicts between biological and morphological species concepts, and add to a growing body of evidence that too many wild potato species are recognized.  相似文献   

3.
Malygin AA  Karpova GG 《FEBS letters》2010,584(21):4396-4400
After resolving the crystal structure of the prokaryotic ribosome, mapping the proteins in the eukaryotic ribosome is a challenging task. We applied RNase H digestion to split the human 40S ribosomal subunit into head and body parts. Mass spectrometry of the proteins in the 40S subunit head revealed the presence of eukaryote-specific ribosomal protein S28e. Recombinant S28e was capable of specific binding to the 3′ major domain of the 18S rRNA (Ka = 8.0 ± 0.5 × 109 M−1). We conclude that S28e has a binding site on the 18S rRNA within the 40S subunit head.

Structured summary

MINT-8044084: S8 (uniprotkb:P62241) and S19 (uniprotkb:P39019) colocalize (MI:0403) by cosedimentation through density gradient (MI:0029)MINT-8044095: S8 (uniprotkb:P62241), S19 (uniprotkb:P39019) and S13 (uniprotkb:P62277) colocalize (MI:0403) by cosedimentation through density gradient (MI:0029)MINT-8044024: S29 (uniprotkb:P62273), S28 (uniprotkb:P62857), S21 (uniprotkb:P63220), S20 (uniprotkb:P60866), S26 (uniprotkb:P62854), S25 (uniprotkb:P62851), S12 (uniprotkb:P25398), S17 (uniprotkb:P08708), S19 (uniprotkb:P39019), S14 (uniprotkb:P62263), S16 (uniprotkb:P62249) and S11 (uniprotkb:P62280) colocalize (MI:0403) by cosedimentation through density gradient (MI:0029)MINT-8044065: S29 (uniprotkb:P62273), S28 (uniprotkb:P62857), S19 (uniprotkb:P39019), S14 (uniprotkb:P62263) and S16 (uniprotkb:P62249) colocalize (MI:0403) by cosedimentation through density gradient (MI:0029)  相似文献   

4.
Xiao F  Lu M  Li J  Zhao T  Yi SY  Thara VK  Tang X  Zhou JM 《Plant physiology》2003,131(3):1239-1249
Pto confers disease resistance to Pseudomonas syringae pv tomato carrying the cognate avrPto gene. Overexpression of Pto under the cauliflower mosaic virus 35S promoter activates spontaneous lesions and confers disease resistance in tomato (Lycopersicon esculentum) plants in the absence of avrPto. Here, we show that these AvrPto-independent defenses require a functional Prf gene. Several Pto-interacting (Pti) proteins are thought to play a role in Pto-mediated defense pathways. To test if interactions with Pti proteins are required for the AvrPto-independent defense responses by Pto overexpression, we isolated several Pto mutants that were unable to interact with one or more Pti proteins, but retained normal interaction with AvrPto. Overexpression of two mutants, Pto(G50S) and Pto(R150S), failed to activate AvrPto-independent defense responses or confer enhanced resistance to the virulent P. s. pv tomato. When introduced into plants carrying 35S::Pto, 35S::Pto(G50S) dominantly suppressed the AvrPto-independent resistance caused by former transgene. 35S::Pto(G50S) also blocked the induction of a number of defense genes by the wild-type 35S::Pto. However, 35S::Pto(G50S) and 35S::Pto(R150S) plants were completely resistant to P. s. pv tomato (avrPto), indicating a normal gene-for-gene resistance. Furthermore, 35S::Pto(G50S) plants exhibited normal induction of defense genes in recognition of avrPto. Thus, the AvrPto-independent defense activation and gene-for-gene resistance mediated by Pto are functionally separable.  相似文献   

5.
The phosphatidylinositol 3–kinase (PI3K) signaling pathway is critical in modulating platelet functions. In the present study, we evaluated the effect of S14161, a recently identified pan-class I PI3K inhibitor, on platelet activation and thrombus formation. Results showed that S14161 inhibited human platelet aggregation induced by collagen, thrombin, U46619, and ADP in a dose-dependent manner. Flow cytometric studies showed that S14161 inhibited convulxin- or thrombin-induced P-selectin expression and fibrinogen binding of single platelet. S14161 also inhibited platelet spreading on fibrinogen and clot retraction, processes mediated by outside-in signaling. Using a microfluidic chamber we demonstrated that S14161 decreased platelet adhesion on collagen-coated surface by about 80%. Western blot showed that S14161 inhibited phosphorylation of Akt at both Ser473 and Thr308 sites, and GSK3β at Ser9 in response to collagen, thrombin, or U46619. Comparable studies showed that S14161 has a higher potential bioavailability than LY294002, a prototypical inhibitor of pan-class I PI3K. Finally, the effects of S14161 on thrombus formation in vivo were measured using a ferric chloride-induced carotid artery injury model in mice. The intraperitoneal injection of S14161 (2 mg/kg) to male C57BL/6 mice significantly extended the first occlusion time (5.05±0.99 min, n = 9) compared to the vehicle controls (3.72±0.95 min, n = 8) (P<0.05), but did not prolong the bleeding time (P>0.05). Taken together, our data showed that S14161 inhibits platelet activation and thrombus formation without significant bleeding tendency and toxicity, and considering its potential higher bioavailability, it may be developed as a novel therapeutic agent for the prevention of thrombotic disorders.  相似文献   

6.
Repair of DNA-targeted anticancer agents is an active area of investigation of both fundamental and clinical interest. However, most studies have focused on a small number of compounds limiting our understanding of both DNA repair and the DNA damage response. S23906 is an acronycine derivative that shows strong activity toward solid tumors in experimental models. S23906 forms bulky monofunctional DNA adducts in the minor groove which leads to destabilization of the double-stranded helix. We now report that S23906 induces formation of DNA double strand breaks that are processed through homologous recombination (HR) but not Non-Homologous End-Joining (NHEJ) repair. Interestingly, S23906 exposure was accompanied by a higher sensitivity of BRCA2-deficient cells compared to other HR deficient cell lines and by an S-phase accumulation in wild-type (wt), but not in BRCA2-deficient cells. Recently, we have shown that S23906-induced S phase arrest was mediated by the checkpoint kinase Chk1. However, its activated phosphorylated form is equally induced by S23906 in wt and BRCA2-deficient cells, likely indicating a role for BRCA2 downstream of Chk1. Accordingly, override of the S phase arrest by either 7-hydroxystaurosporine (UCN-01) or AZD7762 potentiates the cytotoxic activity of S23906 in wt, but not in BRCA2-deficient cells. Together, our findings suggest that the pronounced sensitivity of BRCA2-deficient cells to S23906 is due to both a defective S-phase arrest and the absence of HR repair. Tumors with deficiencies for proteins involved in HR, and BRCA2 in particular, may thus show increased sensitivity to S23906, thereby providing a rationale for patient selection in clinical trials.  相似文献   

7.
The catalytic center (CC) of water oxidation in photosystem II passes through four stepwise increased oxidized states (S(0)-S(4)) before O(2) evolution takes place from 2H(2)O in the S(4) --> S(0) transition. The pattern of the release of the four protons from the CC cannot be followed directly in the medium, because proton release from unknown amino acid residues also takes place. However, pH-independent net charge oscillations of 0:0:1:1 in S(0):S(1):S(2):S(3) have been considered as an intrinsic indicator for the H(+) release from the CC. The net charges have been proposed to be created as the charge difference between electron abstraction and H(+) release from the CC. Then the H(+) release from the CC is 1:0:1:2 for the S(0) --> S(1) --> S(2) --> S(3) --> S(0) transition. Strong support for this conclusion is given in this work with the analysis of the pH-dependent pattern of H(+) release in the medium measured directly by a glass electrode between pH 5.5 and 7.2. Improved and crystallizable photosystem II core complexes from the cyanobacterium Synechococcus elongatus were used as material. The pattern can be explained by protons released from the CC with a stoichiometry of 1:0:1:2 and protons from an amino acid group (pK approximately 5.7) that is deprotonated and reprotonated through electrostatic interaction with the oscillating net charges 0:0:1:1 in S(0):S(1):S(2):S(3). Possible water derivatives that circulate through the S states have been named.  相似文献   

8.
Eukaryotic 5S rRNA hybridizes specifically with 18S rRNA in vitro to form a stable intermolecular RNA:RNA hybrid. We have used 5S rRNA/18S rRNA fragment hybridization studies coupled with ribonuclease digestion and primer extension/chain termination analysis of 5S rRNA:18S rRNA hybrids to more completely map those mouse 5S rRNA and 18S rRNA sequences responsible for duplex formation. Fragment hybridization analysis has defined a 5'-terminal region of 5S rRNA (nucleotides 6-27) which base-pairs with two independent sequences in 18S rRNA designated Regions 1 (nucleotides 1157-1180) and 2 (nucleotides 1324-1339). Ribonuclease digestion of isolated 5S rRNA:18S rRNA hybrids with both single-strand- and double-strand-specific nucleases supports the involvement of this 5'-terminal 5S rRNA sequence in 18S rRNA hybridization. Primer extension/chain termination analysis of isolated 5S rRNA:18S rRNA hybrids confirms the base-pairing of 5S rRNA to the designated Regions 1 and 2 of 18S rRNA. Using these results, 5S rRNA:18S rRNA intermolecular hybrid structures are proposed. Comparative sequence analysis revealed the conservation of these hybrid structures in higher eukaryotes and the same but smaller core hybrid structures in lower eukaryotes and prokaryotes. This suggests that the 5S rRNA:16S/18S rRNA hybrids have been conserved in evolution for ribosome function.  相似文献   

9.
Twelve hitherto unrecognizedSalmonella types are described. S. heerlen (11 : i : 1,6) andS. sloterdijk (1, 4, 12, 27 : z 35 : z 6) were isolated from patients in the Netherlands,S. maartensdijk (40 : g, p) was isolated from a healthy calf,S. maastricht (11 : z 41 : 1, 2(7)) from imported fishmeal,S. parera (11 : z 4, z 23 : -.) from water on the island Bonaire,S. putten (13, 23, 36 : d : 1, w),S. hoograven (50 : z 10 : z 6 : z 42),S. schalkwijk ((6), 14, (24) : i : e, n, ...),S. hilversum (30 : k : 1, 2) andS. harmelen (51 : z 4, z 23 : -.) from reptiles,S. breukelen (6, 8 : 1, z 13 : e, n, z 15) from a cuscus andS. maarssen (9, 46 : z 4, z 24 : z 39 : z 42) from a lizard.  相似文献   

10.
The present study investigated the long-lasting effects of prenatal repeated restraint stress on social behavior and anxiety, as well as its repercussions on oxytocin (OT) and vasopressin (VP)-positive neurons of the paraventricular (PVN) and supraoptic (SON) nuclei from stressed pups in adulthood. Female Wistar rats were exposed to restraint stress in the last 7 days of pregnancy. At birth, pups were cross-fostered and assigned to the following groups: prenatally non-stressed offspring raised by prenatally non-stressed mothers (NS:NS), prenatally non-stressed offspring raised by prenatally stressed mothers (S:NS), prenatally stressed offspring raised by prenatally non-stressed mothers (NS:S), prenatally stressed offspring raised by prenatally stressed mothers (S:S). As adults, male prenatally stressed offspring raised both by stressed mothers (S:S group) and non-stressed ones (NS:S group) showed impaired social memory and interaction. In addition, when both adverse conditions coexisted (S:S group), increased anxiety-like behavior and aggressiveness was observed in association with a decrease in the number of OT-positive magnocellular neurons, VP-positive magnocellular and parvocellular neurons of the PVN. The NS:S group exhibited a reduction in the amount of VP-positive magnocellular neurons compared to the S:NS. Thus, the social behavior deficits observed in the S:S and NS:S groups may be only partially associated with these alterations to the peptidergic systems. No changes were shown in the OT and VP cellular composition of the SON nucleus. Nevertheless, it is clear that a special attention should be given to the gestational period, since stressful events during this time may be related to the emergence of behavioral impairments in adulthood.  相似文献   

11.
利用gateway技术从拟南芥中克隆了3个蛋白磷酸酶2C基因At5G66080、At1G68410和At5G06750,3个基因的ORF全长分别为1 158 bp、1 311 bp和1 182 bp,分别编码一条385、376和393个氨基酸残基的多肽.构建了3个基因的植物表达载体35S:GFP:At5G66080、35S:GFP:At1G68410和35S:GFP:At5G06750,采用基因枪法进行的洋葱表皮细胞GFP瞬时表达实验表明,荧光信号主要分布在细胞核上,显示这3个基因的产物可能在细胞核上发挥作用.利用实时荧光定量PCR研究At5G66080、At1G68410和At5G06750基因在不同组织中的表达特性,结果表明:3个基因在各个器官均有表达,但表达量不同;At5G66080、At1G68410和At5G06750基因在花中表达量最大;At5G66080和At5G06750基因在根、叶和叶柄中的表达量次之,在茎中的表达量最低;At1G68410基因在根中的表达量次之,在茎、叶和叶柄中的表达量较低.  相似文献   

12.
Two blazeispirane derivatives including blazeispirols G and I were isolated from the cultured mycelia of the fungus Agaricus blazei Murill and were established to be (20S, 22S, 23R, 24S)-14 beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-triene-11 alpha,23-diol and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-23,28-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. Furthermore, four blazeispirol derivatives blazeispirols, U, V, V(1) and Z(1) were isolated form the same source described above. Their structures were determined to be (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxyergosta-4,6,8,11-tetraen-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 alpha,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 beta,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxy-4,5-seco-ergosta-6,8-diene-3,5-dione by extensive 1 D and 2D NMR spectral data.  相似文献   

13.
14.
Small mammals were trapped on five islands for short periods during the summers of 1964 and 1965, with the following results:
Handa: Rattus norvegicus only, probably no other species present.
Muck: Sorex araneus, S. minutus, Apodemus sylvaticus and Microtus agrestis; R. norvegicus also present.
Pabay: S. minutus and Neomys fodiens ; probably no other species present.
Scalpay: S. araneus, S. minutus and M. agrestis.
Soay: S. araneus and S. minutus ; rodents almost certainly absent.
Ectoparasites (fleas and Acarina) collected from these small mammals are tabulated.  相似文献   

15.
In the filamentous fungus Podospora anserina, ribosomal proteins of 60 mutants impaired in the control of translational fidelity have been submitted to electrophoretic analysis. The "four corners" system combining four different two-dimensional polyacrylamide gel electrophoretic systems has been used. An altered electrophoretic pattern has been observed for 12 mutants. In mutants su3, su12 and su11 (decreased translational fidelity), proteins S1, S7 and S8, respectively, are altered. For AS mutants (increased translational fidelity), proteins S9, S12 and S19, respectively, are altered in AS9, AS1 and AS6 mutants, and protein S29 is lacking in AS3 mutants. The data suggest that five of these genes (at least) are the structural genes for the relevant proteins (su3:S1, su12:S7, AS1:S12, AS6:S19, AS9:S9), while the AS3 gene may code for a modifying enzyme.  相似文献   

16.
Using reverse phase HPLC, we have been able to quantify the protein compositions of reconstituted 30S ribosomal subunits, formed either with the full complement of 30S proteins in the reconstitution mix or with a single protein omitted. We denote particles formed in the latter case as SPORE (single protein omission reconstitution) particles. An important goal in 30S reconstitution studies is the formation of reconstituted subunits having uniform protein composition, preferably corresponding to one copy of each protein per reconstituted particle. Here we describe procedures involving variation of the protein:rRNA ratio that approach this goal. In SPORE particles the omission of one protein often results in the partial loss in uptake of other proteins. We also describe procedures to increase the uptake of such proteins into SPORE particles, thus enhancing the utility of the SPORE approach in defining the role of specific proteins in 30S structure and function. The losses of proteins other than the omitted protein provide a measure of protein:protein interaction within the 30S subunit. Most of these losses are predictable on the basis of other such measures. However, we do find evidence for several long-range protein:protein interactions (S6:S3, S6:S12, S10:S16, and S6:S4) that have not been described previously.  相似文献   

17.
Four new des-A-ergostane derivatives including blazeispirols B, C, E and F were isolated from the cultured mycelia of fungus Agaricus blazei Murill and were established to be (20S, 22R, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraen-23-ol; (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-trien-23-ol; (20S, 22S, 23R, 24S)-14beta, 22: 22, 25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-19,23-diol and (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-des-A-ergosta-5,7,9-triene-5,23-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A.  相似文献   

18.
目的:探索利用酿酒酵母系统表达乙型肝炎病毒(HBV)preS/S基因。方法:利用PCR技 术,以HBV病毒DNA为模板,体外扩增HBV preS/S基因。然后构建重组表达载体pESC-preS/S。 用LiAc法转化酿酒酵母YPH50,选取重组菌进行培养,并诱导表达外源蛋白。提取蛋白浓缩后 进行SDS-PAGE分析,并经Western blot分析鉴定。结果:实验结果表明重组菌能够表达HBV preS/S蛋白。结论:利用酿酒酵母系统可成功表达HBV preS/S基因,为制备新型预防性疫苗提供 条件。  相似文献   

19.
15 new species are described: Sect.Sclerocalycinae:S. farsistanica, S. stapfii. — Sect.Spergulifoliae:S. paktiensis. — Sect.Auriculatae:S. caroli-henrici, S. daënensis, S. gertraudiae, S. nizvana, S. oligophylla, S. persepolitana, S. pseudaucheriana, S. pseudonurensis, S. renzii, S. salangensis, S. sojakii. — Sect.Brachypodae:S. rasvandica. — All the new species are from Iran with exception ofS. paktiensis andS. parvanica which are from Afghanistan.
Florae Iranicae praecursores 46–60. — Praecursores praecurrentes in Pl. Syst. Evol.142: 239–246 (1983).  相似文献   

20.
The biogas production and some biochemical parameters of anaerobic fermentation at 30 degrees C for 40 days were studied for eight experimental groups of fermentation media, as affected by two factors: (1) the type of the animal waste (sheep waste, S and goat waste, G), and (2) the ratio of waste to olive cake which constitutes four levels (100:0 for S1 and G1; 80:20 for S2 and G2; 60:40 for S3 and G3 and 40:60 for S4 and G4). The results indicated that there was a significant decrease (P < 0.05) in the biogas production with an increase in the proportion of olive cake in place of animal waste. However, there was a significant increase in the biogas production for the S4 treatment compared with G4, reflecting an effect induced by the type of animal waste. The biogas production amounted to (l/kg VS/40 d): 62 (S1), 53 (S2), 49 (S3), 40 (S4), 58 (G1), 50 (G2), 44 (G3) and 25 (G4). The reduction in total solid (TS) weight, volatile solids (VS), neutral-detergent fiber decreased significantly (P < 0.05) with the increase in olive cake proportion in the digester. The reductions in VS were (% in DM): 58.2 (S1), 37.8 (S2), 26.6 (S3), 22.6 (S4), 58.1 (G1), 36 (G2), 33.4 (G3), 14.4 (G4). The rates of energy consumption were (MJ/kg DM/40 d): 15.36 (S1), 10.12 (S2), 7.84 (S3), 6.68 (S4), 14.16 (G1), 9.68 (G2), 8.41 (G3), 3.29 (G4).  相似文献   

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