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1.
Dragan Nonic John C. Bliss Vojislav Milijic Nenad Petrovic Mersudin Avdibegovic Milan Mataruga 《Small-Scale Forestry》2011,10(4):435-455
Small-scale forestry in Serbia is characterized by high fragmentation of properties, a large number of parcels and forest
owners. Numerous activities for private forest owners in Serbia supported by the State, FAO and CEPF have resulted in an increased
interest of owners in forming private forest owners’ associations (PFOA). The goal of this paper is to explore preconditions
that are necessary for organizing private forest owners in Serbia into effective associations. In order to reach this goal,
results of PRIFORT project were used. The over-arching research questions of this paper are: “What is the level of interest
among forest owners in forming owners’ associations?”; “Why has forest owner interest in organizing developed so slowly?”
and “What are the necessary preconditions for the development of private forest owners’ organizations in the country?” In
order to answer these questions, quantitative survey with 42 close, open and Likert scale questions was conducted. Sample
size was determined following Malhotra’s proportion method and, in total, 350 private forest owners, from nine municipalities
were interviewed. Results of this paper show that majority of respondents are very little or not at all aware of existing
legislation. Almost half of respondents consider that their interests are not represented well. Although about 50% of interviewed
forest owners miss interest organization, only 0,3% are members of PFOA. More than 70% are ready to join association, if it
would provide some economic advantages. 相似文献
2.
Mammalian fatty acid synthase is a large multienzyme that catalyzes all steps of fatty acid synthesis. We have determined its crystal structure at 3.2 angstrom resolution covering five catalytic domains, whereas the flexibly tethered terminal acyl carrier protein and thioesterase domains remain unresolved. The structure reveals a complex architecture of alternating linkers and enzymatic domains. Substrate shuttling is facilitated by flexible tethering of the acyl carrier protein domain and by the limited contact between the condensing and modifying portions of the multienzyme, which are mainly connected by linkers rather than direct interaction. The structure identifies two additional nonenzymatic domains: (i) a pseudo-ketoreductase and (ii) a peripheral pseudo-methyltransferase that is probably a remnant of an ancestral methyltransferase domain maintained in some related polyketide synthases. The structural comparison of mammalian fatty acid synthase with modular polyketide synthases shows how their segmental construction allows the variation of domain composition to achieve diverse product synthesis. 相似文献
3.
Ataide SF Schmitz N Shen K Ke A Shan SO Doudna JA Ban N 《Science (New York, N.Y.)》2011,331(6019):881-886
Cotranslational targeting of membrane and secretory proteins is mediated by the universally conserved signal recognition particle (SRP). Together with its receptor (SR), SRP mediates the guanine triphosphate (GTP)-dependent delivery of translating ribosomes bearing signal sequences to translocons on the target membrane. Here, we present the crystal structure of the SRP:SR complex at 3.9 angstrom resolution and biochemical data revealing that the activated SRP:SR guanine triphosphatase (GTPase) complex binds the distal end of the SRP hairpin RNA where GTP hydrolysis is stimulated. Combined with previous findings, these results suggest that the SRP:SR GTPase complex initially assembles at the tetraloop end of the SRP RNA and then relocalizes to the opposite end of the RNA. This rearrangement provides a mechanism for coupling GTP hydrolysis to the handover of cargo to the translocon. 相似文献
4.
Abelson JF Kwan KY O'Roak BJ Baek DY Stillman AA Morgan TM Mathews CA Pauls DL Rasin MR Gunel M Davis NR Ercan-Sencicek AG Guez DH Spertus JA Leckman JF Dure LS Kurlan R Singer HS Gilbert DL Farhi A Louvi A Lifton RP Sestan N State MW 《Science (New York, N.Y.)》2005,310(5746):317-320
Tourette's syndrome (TS) is a genetically influenced developmental neuropsychiatric disorder characterized by chronic vocal and motor tics. We studied Slit and Trk-like 1 (SLITRK1) as a candidate gene on chromosome 13q31.1 because of its proximity to a de novo chromosomal inversion in a child with TS. Among 174 unrelated probands, we identified a frameshift mutation and two independent occurrences of the identical variant in the binding site for microRNA hsa-miR-189. These variants were absent from 3600 control chromosomes. SLITRK1 mRNA and hsa-miR-189 showed an overlapping expression pattern in brain regions previously implicated in TS. Wild-type SLITRK1, but not the frameshift mutant, enhanced dendritic growth in primary neuronal cultures. Collectively, these findings support the association of rare SLITRK1 sequence variants with TS. 相似文献
5.
Eukaryotic ribosomes are substantially larger and more complex than their bacterial counterparts. Although their core function is conserved, bacterial and eukaryotic protein synthesis differ considerably at the level of initiation. The eukaryotic small ribosomal subunit (40S) plays a central role in this process; it binds initiation factors that facilitate scanning of messenger RNAs and initiation of protein synthesis. We have determined the crystal structure of the Tetrahymena thermophila 40S ribosomal subunit in complex with eukaryotic initiation factor 1 (eIF1) at a resolution of 3.9 angstroms. The structure reveals the fold of the entire 18S ribosomal RNA and of all ribosomal proteins of the 40S subunit, and defines the interactions with eIF1. It provides insights into the eukaryotic-specific aspects of protein synthesis, including the function of eIF1 as well as signaling and regulation mediated by the ribosomal proteins RACK1 and rpS6e. 相似文献
6.
Riboswitches are untranslated regions of messenger RNA, which adopt alternate structures depending on the binding of specific metabolites. Such conformational switching regulates the expression of proteins involved in the biosynthesis of riboswitch substrates. Here, we present the 2.9 angstrom-resolution crystal structure of the eukaryotic Arabidopsis thaliana thiamine pyrophosphate (TPP)-specific riboswitch in complex with its natural ligand. The riboswitch specifically recognizes the TPP via conserved residues located within two highly distorted parallel "sensor" helices. The structure provides the basis for understanding the reorganization of the riboswitch fold upon TPP binding and explains the mechanism of resistance to the antibiotic pyrithiamine. 相似文献
7.
All steps of fatty acid synthesis in fungi are catalyzed by the fatty acid synthase, which forms a 2.6-megadalton alpha6beta6 complex. We have determined the molecular architecture of this multienzyme by fitting the structures of homologous enzymes that catalyze the individual steps of the reaction pathway into a 5 angstrom x-ray crystallographic electron density map. The huge assembly contains two separated reaction chambers, each equipped with three sets of active sites separated by distances up to approximately 130 angstroms, across which acyl carrier protein shuttles substrates during the reaction cycle. Regions of the electron density arising from well-defined structural features outside the catalytic domains separate the two reaction chambers and serve as a matrix in which domains carrying the various active sites are embedded. The structure rationalizes the compartmentalization of fatty acid synthesis, and the spatial arrangement of the active sites has specific implications for our understanding of the reaction cycle mechanism and of the architecture of multienzymes in general. 相似文献
8.
Tančić Živanov Sonja Dedić Boško Dimitrijević Aleksandra Dušanić Nenad Jocić Siniša Miklič Vladimir Kovačević Branislav Miladinović Dragana 《植物病害和植物保护杂志》2019,126(6):565-573
Journal of Plant Diseases and Protection - The study assessed the genetic variability among Macrophomina phaseolina (Tassi) Goid. isolates originating from six different countries (Turkey,... 相似文献
9.
Vasić Tanja Jevremović Darko Krnjaja Vesna Živković Sanja Trkulja Vojislav 《植物病害和植物保护杂志》2021,128(5):1357-1361
Journal of Plant Diseases and Protection - In autumn 2018, daffodil (narcissus) plants with basal bulb rot were noticed in a plantation in locality Jasika, Serbia. Morphological characterization... 相似文献
10.
Živković Sanja Vasić Tanja Ivanović Milan Jevremović Darko Marković Jordan Trkulja Vojislav 《植物病害和植物保护杂志》2019,126(5):479-483
Journal of Plant Diseases and Protection - During a survey from 2004 to 2016, symptoms of grapevine dieback were observed in six vineyards in Serbia. Symptoms initially appeared as small,... 相似文献