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61.
Anna Filippova Irina Lyapina Ilya Kirov Victor Zgoda Alexey Belogurov Anna Kudriaeva Vadim Ivanov Igor Fesenko 《Journal of peptide science》2019,25(2)
Plant secretome comprises dozens of secreted proteins. However, little is known about the composition of the whole secreted peptide pools and the proteases responsible for the generation of the peptide pools. The majority of studies focus on target detection and characterization of specific plant peptide hormones. In this study, we performed a comprehensive analysis of the whole extracellular peptidome, using moss Physcomitrella patens as a model. Hundreds of modified and unmodified endogenous peptides that originated from functional and nonfunctional protein precursors were identified. The plant proteases responsible for shaping the pool of endogenous peptides were predicted. Salicylic acid (SA) influenced peptide production in the secretome. The proteasome activity was altered upon SA treatment, thereby influencing the composition of the peptide pools. These results shed more light on the role of proteases and posttranslational modification in the “active management” of the extracellular peptide pool in response to stress conditions. It also identifies a list of potential peptide hormones in the moss secretome for further analysis. 相似文献
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63.
Kevin Ni Amar Gill Danting Cao Kengo Koike Kelly S. Schweitzer Stavros Garantziotis Irina Petrache 《Biochemistry and Biophysics Reports》2019
During inflammation, the covalent linking of the ubiquitous extracellular polysaccharide hyaluronan (HA) with the heavy chains (HC) of the serum protein inter alpha inhibitor (IαI) is exclusively mediated by the enzyme tumor necrosis factor α (TNFα)-stimulated-gene-6 (TSG-6). While significant advances have been made regarding how HC-modified HA (HC-HA) is an important regulator of inflammation, it remains unclear why HC-HA plays a critical role in promoting survival in intraperitoneal lipopolysaccharide (LPS)-induced endotoxemia while exerting only a modest role in the outcomes following intratracheal exposure to LPS. To address this gap, the two models of intraperitoneal LPS-induced endotoxic shock and intratracheal LPS-induced acute lung injury were directly compared in TSG-6 knockout mice and littermate controls. HC-HA formation, endogenous TSG-6 activity, and inflammatory markers were assessed in plasma and lung tissue. TSG-6 knockout mice exhibited accelerated mortality during endotoxic shock. While both intraperitoneal and intratracheal LPS induced HC-HA formation in lung parenchyma, only systemically-induced endotoxemia increased plasma TSG-6 levels and intravascular HC-HA formation. Cultured human lung microvascular endothelial cells secreted TSG-6 in response to both TNFα and IL1β stimulation, indicating that, in addition to inflammatory cells, the endothelium may secrete TSG-6 into circulation during systemic inflammation. These data show for the first time that LPS-induced systemic inflammation is uniquely characterized by significant vascular induction of TSG-6 and HC-HA, which may contribute to improved outcomes of endotoxemia. 相似文献
64.
Irina V. Kravchenko Vladimir A. Furalyov Vladimir O. Popov 《Biochemistry and Biophysics Reports》2019
The effects of potassium chloride on the expression of IGF-1 splice forms and myoblast proliferation were investigated. KCl at the concentrations of 7–12 mM stimulated the synthesis of IGF-1 and mechano growth factor (MGF) in murine myoblasts as well as in myotubes both at the mRNA and protein levels. Pan-calcium channel blocker CdCl2 completely abolished stimulation of growth factor expression, whereas blocker of HCN and Nav1.4 channels ZD7288 drastically reduced it. In addition, potassium chloride stimulated myoblast proliferation, while IGF-1 autocrine signaling inhibition partially suppressed these mitogenic effects. 相似文献
65.
Sofía Ruiz-Cruz Andrea Erazo Garzon Philip Kelleher Francesca Bottacini Solvej Østergaard Breum Horst Neve Knut J. Heller Finn K. Vogensen Simon Palussière Pascal Courtin Marie-Pierre Chapot-Chartier Evgeny Vinogradov Irina Sadovskaya Jennifer Mahony Douwe van Sinderen 《Microbial biotechnology》2022,15(12):2875-2889
The first step in phage infection is the recognition of, and adsorption to, a receptor located on the host cell surface. This reversible host adsorption step is commonly followed by an irreversible event, which involves phage DNA delivery or release into the bacterial cytoplasm. The molecular components that trigger this latter event are unknown for most phages of Gram-positive bacteria. In the current study, we present a comparative genome analysis of three mutants of Lactococcus cremoris 3107, which are resistant to the P335 group phage TP901-1 due to mutations that affect TP901-1 DNA release. Through genetic complementation and phage infection assays, a predicted lactococcal three-component glycosylation system (TGS) was shown to be required for TP901-1 infection. Major cell wall saccharidic components were analysed, but no differences were found. However, heterologous gene expression experiments indicate that this TGS is involved in the glucosylation of a cell envelope-associated component that triggers TP901-1 DNA release. To date, a saccharide modification has not been implicated in the DNA delivery process of a Gram-positive infecting phage. 相似文献
66.
An anomeric phosphodiester linkage formed by a glycosyl phosphate unit and a hydroxyl group of another monosaccharide is found in many glycopolymers of the outer membrane in bacteria (e.g., capsular polysaccharides and lipopolysaccharides), yeasts and protozoa. The polymers (phosphoglycans) composed of glycosyl phosphate (or oligoglycosyl phosphate) repeating units could be chemically classified as poly(glycosyl phosphates). Their importance as immunologically active components of the cell wall and/or capsule of numerous microorganisms upholds the need to develop routes for the chemical preparation of these biopolymers. In this paper, we (1) present a review of the primary structures (known to date) of natural phosphoglycans from various sources, which contain glycosyl phosphate units, and (2) discuss different approaches and recent achievements in the synthesis of glycosyl phosphosaccharides and poly(glycosyl phosphates). 相似文献
67.
The formation of ice crystals within cells (IIF) is lethal. The classical approach to avoiding it is to cool cells slowly enough so that nearly all their supercooled freezable water leaves the cell osmotically before they have cooled to a temperature that permits IIF. An alternative approach is to cool the cell rapidly to just above its ice nucleation temperature, and hold it there long enough to permit dehydration. Then, the cell is cooled rapidly to -70 degrees C or below. This approach, often called interrupted rapid cooling, is the subject of this paper. Mouse oocytes were suspended in 1.5M ethylene glycol (EG)/PBS, rapidly cooled (50 degrees C/min) to -25 degrees C and held for 5, 10, 20, 30, or 40 min before being rapidly cooled (50 degrees C/min) to -70 degrees C. In cells held for 5 min, IIF (flashing) occurred abruptly during the second rapid cool. As the holding period was increased to 10 and 20 min, fewer cells flashed during the cooling and more turned black during warming. Finally, when the oocytes were held 30 or 40 min, relatively few flashed during either cooling or warming. Immediately upon thawing, these oocytes were highly shrunken and crenated. However, upon warming to 20 degrees C, they regained most of their normal volume, shape, and appearance. These oocytes have intact cell membranes, and we refer to them as survivors. We conclude that 30 min at -25 degrees C removes nearly all intracellular freezable water, the consequence of which is that IIF occurs neither during the subsequent rapid cooling to -70 degrees C nor during warming. 相似文献
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69.
Species of the mitosporic filamentous fungal genus Trichoderma are prominent producers of both short (7-11 residues) and long (18-20 residues) peptaibols and peptaibiotics, which are thought to be involved in their interaction with other living systems. Numerous reviews are available regarding biodiversity, structure, and mode of action of these peptide derivatives, but little emphasis has been paid to the physiology and genetics of their formation. In this review article, we used the recent knowledge on biosynthesis and production of these components to speculate on some of the unknown points. We also highlight areas where further research is most urgently needed. 相似文献
70.
Voznesenskaya T Makogon N Bryzgina T Sukhina V Grushka N Alexeyeva I 《Reproductive biology》2007,7(3):207-220
Experimental immune ovarian failure induced in CBA mice by either administration of xenogenic anti-ovarian antibodies or immunization with allogenic ovarian extracts impaired the meiotic maturation of oocytes and increased apoptosis of follicular cells. Immunization was accompanied with the inflammation and active immune reaction, as shown by the enlargement of regional lymph nodes, the increase of apoptosis in cultured lymph node cells and the increase of band and segmented neutrophil percentage in the blood. Triple injections of melatonin (5 mg/kg of the body weight) an hour before antibodies administration restored the meiotic maturation of oocytes and supported the survival of follicular and lymph node cells. In contrast, melatonin application upon immunization was not effective to prevent the ovary impairment and cell death. It is concluded that melatonin protects against immune ovary failure induced by xenogenic anti-ovarian antibodies. 相似文献