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101.
In the year 2000, a fungus was isolated from rotting lemon (Citrus limon) fruit in the Kahnouj region, south‐eastern Iran and subsequently identified as Ceratocystis radicicola (anamorph: Chalara sp.). A pathogenicity test was carried out to fulfil Koch's postulates. The pathogen could only enter the ripen lemon fruit and cause the rot disease through the wounds and cracks. The fungus was also pathogenic on fruit of other citrus species as well as date palm (Phoenix dactylifera). Symptom development was slow on fruits on the tree but accelerated after fruit harvest.  相似文献   
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103.
Structural basis for FGF receptor dimerization and activation.   总被引:25,自引:0,他引:25  
The crystal structure of FGF2 bound to a naturally occurring variant of FGF receptor 1 (FGFR1) consisting of immunoglobulin-like domains 2 (D2) and 3 (D3) has been determined at 2.8 A resolution. Two FGF2:FGFR1 complexes form a 2-fold symmetric dimer. Within each complex, FGF2 interacts extensively with D2 and D3 as well as with the linker between the two domains. The dimer is stabilized by interactions between FGF2 and D2 of the adjoining complex and by a direct interaction between D2 of each receptor. A positively charged canyon formed by a cluster of exposed basic residues likely represents the heparin-binding site. A general model for FGF- and heparin-induced FGFR dimerization is inferred from the crystal structure, unifying a wealth of biochemical data.  相似文献   
104.
Among the seven tyrosine autophosphorylation sites identified in the intracellular domain of tyrosine kinase fibroblast growth factor receptor-1 (FGFR1), five of them are dispensable for FGFR1-mediated mitogenic signaling. The possibility of dissociating the mitogenic activity of basic FGF (FGF2) from its urokinase-type plasminogen activator (uPA)-inducing capacity both at pharmacological and structural levels prompted us to evaluate the role of these autophosphorylation sites in transducing FGF2-mediated uPA upregulation. To this purpose, L6 myoblasts transfected with either wild-type (wt) or various FGFR1 mutants were evaluated for the capacity to upregulate uPA production by FGF2. uPA was induced in cells transfected with wt-FGFR1, FGFR1-Y463F, -Y585F, -Y730F, -Y766F, or -Y583/585F mutants. In contrast, uPA upregulation was prevented in L6 cells transfected with FGFR1-Y463/583/585/730F mutant (FGFR1–4F) or with FGFR1-Y463/583/585/730/766F mutant (FGFR1–5F) that retained instead a full mitogenic response to FGF2; however, preservation of residue Y730 in FGFR1-Y463/583/585F mutant (FGFR1–3F) and FGFR1-Y463/583/585/766F mutant (FGFR1–4Fbis) allows the receptor to transduce uPA upregulation. Wild-type FGFR1, FGFR1–3F, and FGFR1–4F similarly bind to a 90-kDa tyrosine-phosphorylated protein and activate Shc, extracellular signal-regulated kinase (ERK)2, and JunD after stimulation with FGF2. These data, together with the capacity of the ERK kinase inhibitor PD 098059 to prevent ERK2 activation and uPA upregulation in wt-FGFR1 cells, suggest that signaling through the Ras/Raf-1/ERK kinase/ERK/JunD pathway is necessary but not sufficient for uPA induction in L6 transfectants. Accordingly, FGF2 was able to stimulate ERK1/2 phosphorylation and cell proliferation, but not uPA upregulation, in L6 cells transfected with the FGFR1-Y463/730F mutant, whereas the FGFR1-Y583/585/730F mutant was fully active. We conclude that different tyrosine autophosphorylation requirements in FGFR1 mediate cell proliferation and uPA upregulation induced by FGF2 in L6 cells. In particular, phosphorylation of either Y463 or Y730, dispensable for mitogenic signaling, represents an absolute requirement for FGF2-mediated uPA induction.  相似文献   
105.
It was reported that bovine α-lactalbumin (BLA) as an important whey protein can be utilized as valuable vehicle for metal ions. The goal of this study was to investigate the interaction of BLA with bisdemethoxycurcumin (BDMC), Diacetylcurcumin (DAC), and diacetylbisdemethoxycurcumin (DABC) as three bioactive compounds by fluorescence quenching measurements and docking studies. It was observed that these ligands come closer to tryptophan residues and quench their emission without any change in their micro region polarity. The Stern–Volmer equation which is the best model to provide information about the interaction between small bioactive molecules and proteins was used to obtain the binding constants and the binding stoichiometry. Information about the extent of resonance energy transfer and Förster’s distance between donor and acceptor was estimated. Thermodynamic parameters confirmed that the final BDMC–BLA complex was stabilized by hydrogen bonds, whereas the final DABC–BLA and DAC–BLA complexes were stabilized by hydrophobic bonds which are in accordance with their chemical structures. Both the synchronous and docking studies verified that theTrp-26 which is the most exposed Tryptophan residue has the most contribution in the binding process. The Förster’s distances between bound ligands and tryptophans were in agreement with the measured distances by docking studies. The obtained achievements confirmed that there are considerable binding interactions between these curcuminoids and BLA.  相似文献   
106.
A checklist of 39 species of the genus Tomosvaryella Aczél (Diptera, Pipunculidae) known from the Middle East is provided. A new species, T. hamata Majnon Jahromi &; Kehlmaier sp. n. is described from southern Iran and diagnostic characters of male and female terminalia are illustrated. Tomosvaryella dentiterebra (Collin, 1949 Collin, J. E. (1949): Results of the Armstrong College Expedition to Siwa Oasis (Libyan Desert), 1935, under the leadership of Prof. J. Orner-Cooper. Diptera Empididae, Dolichopodidae, Aschiza and Acalypterae. Bulletin de la Societe Fouad Ierd'Entomologie, 33, 75225. [Google Scholar]) is redescribed and male and female terminalia are illustrated for the first time. A phylogenetic maximum-likelihood analysis and uncorrected pairwise genetic distances of 18 out of 22 Iranian species of Tomosvaryella based on DNA barcodes of the mitochondrial COI gene are presented and also discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:FF8C116D-0C92-431A-B52C-11F3711B6A62  相似文献   
107.
108.
Bioprocess and Biosystems Engineering - In this article, availability and control of water in solid-state fermentation (SSF) were investigated. Based on passive transport of water through plasma...  相似文献   
109.
110.
The problem of deterioration of art works is particularly relevant in countries like Iran that are rich in cultural heritage. According to UNESCO data, Iran holds the tenth rank in a list of countries possessing the highest number of monuments belonging to the world cultural heritage. Archaeological areas, buildings, mosques, statues, museums and objects are all exposed to different biogenic and abiogenic stresses under generally aggressive climatic conditions. Lichens and fungi are known to actively decompose stone surfaces. This process is both physical and chemical in nature and often reaches deep below the stone surfaces. This is caused by chemical and physical interactions of the microbiota with the fluctuating and often drastically changing environmental conditions. Here, we describe and analyze the mainly physical degradation by invading fungal hyphae between stone crystals and a generally destabilizing stone texture. In addition to physical deterioration, organic acids produced by lichens enhance the chemical decomposing processes. In this work, penetration of hyphal bundles as well as individual fungi was studied, and the biodeteriorating patterns were documented and compared to general physical–chemical weathering phenomena. Several strains of aggressive black yeast-like fungi and bacteria were isolated and cultivated and will be described in a taxonomical context with many other isolates from different localities using physiological, morphological and molecular data.  相似文献   
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