Relevant bibliographies by topics / Biological Active Molecules

Academic literature on the topic 'Biological Active Molecules'

Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

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Journal articles on the topic "Biological Active Molecules"

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Freeman, Amihay, Yael Dror, Carmit Ophir Porat, Noa Hadar, and Yossi Shacham Diamand. "Silver-Coated Biologically Active Protein Hybrids: Antimicrobial Applications." Applied Mechanics and Materials 749 (April 2015): 453–56. http://dx.doi.org/10.4028/www.scientific.net/amm.749.453.

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Novel hybrids, comprised of a biologically active protein molecule core, coated with a thin outer layer of porous metallic silver, were developed in our lab. By the conjugation of silver reducing polymer to the surface of soluble, molecular, biologically active protein molecules and subsequent addition of silver salt, electroless silver deposition, culminating in thin porous metallic coating, was directed to the surface of the protein molecules. The silver-protein hybrids thus obtained, presenting novel nanoparticles several nanometers in size, retained their solubility and biological activity.The silver coating combined with the retained biological activity of its protein core, paved the way to a series of biomedical applications of these hybrids including "wiring" of the active site of oxido-reductase enzyme to electrodes, imaging of the presence of targeted ligands displayed on cancer cell surface and antimicrobial enzymatically attenuated release of silver ions.In this presentation we shall overview the technology of protein-silver hybrid's fabrication and analytical applications of silver-glucose oxidase and silver-Avidin hybrids, followed by feasibility demonstration of using silver-glucose oxidase hybrid as novel antibacterial and antifungal agent.
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Rana, Aniruddhasinh M., Kishor R. Desai, and Smita Jauhari. "Rhodanine-based biologically active molecules: synthesis, characterization, and biological evaluation." Research on Chemical Intermediates 40, no. 2 (January 22, 2013): 761–77. http://dx.doi.org/10.1007/s11164-012-1001-3.

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Insuasty, Daniel, Juan Castillo, Diana Becerra, Hugo Rojas, and Rodrigo Abonia. "Synthesis of Biologically Active Molecules through Multicomponent Reactions." Molecules 25, no. 3 (January 24, 2020): 505. http://dx.doi.org/10.3390/molecules25030505.

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Focusing on the literature progress since 2002, the present review explores the highly significant role that multicomponent reactions (MCRs) have played as a very important tool for expedite synthesis of a vast number of organic molecules, but also, highlights the fact that many of such molecules are biologically active or at least have been submitted to any biological screen. The selected papers covered in this review must meet two mandatory requirements: (1) the reported products should be obtained via a multicomponent reaction; (2) the reported products should be biologically actives or at least tested for any biological property. Given the diversity of synthetic approaches utilized in MCRs, the highly diverse nature of the biological activities evaluated for the synthesized compounds, and considering their huge structural variability, much of the reported data are organized into concise schemes and tables to facilitate comparison, and to underscore the key points of this review.
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Karolak-Wojciechowska, J., and A. Fruzinski. "Spacer conformation in biologically active molecules." Pure and Applied Chemistry 76, no. 5 (January 1, 2004): 959–64. http://dx.doi.org/10.1351/pac200476050959.

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Based on our contemporary studies on the structures of biologically active molecules, we focus our attention on the aliphatic chain and its conformation. That flexible spacer definitely influenced the balanced position of all pharmacophoric points in molecules of biological ligands. The one atomic linker and two or three atomic spacers with one heteroatom X =O, S, CH2, NH have been taken into account. The conformational preferences clearly depend on the heteroatom X. In the discussion, we utilize our own X-ray data, computation chemistry methods, population analysis, and statistical data from the Cambridge Structural Database (CSD).
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LIU, Yan, and Rong GUO. "Interaction between organized assemblies of amphiphilic molecules and biological active molecules." Chinese Science Bulletin 62, no. 6 (November 14, 2016): 486–97. http://dx.doi.org/10.1360/n972016-00426.

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Smith, David P. "Active learning in the lecture theatre using 3D printed objects." F1000Research 5 (June 3, 2016): 61. http://dx.doi.org/10.12688/f1000research.7632.2.

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The ability to conceptualize 3D shapes is central to understanding biological processes. The concept that the structure of a biological molecule leads to function is a core principle of the biochemical field. Visualisation of biological molecules often involves vocal explanations or the use of two dimensional slides and video presentations. A deeper understanding of these molecules can however be obtained by the handling of objects. 3D printed biological molecules can be used as active learning tools to stimulate engagement in large group lectures. These models can be used to build upon initial core knowledge which can be delivered in either a flipped form or a more didactic manner. Within the teaching session the students are able to learn by handling, rotating and viewing the objects to gain an appreciation, for example, of an enzyme’s active site or the difference between the major and minor groove of DNA. Models and other artefacts can be handled in small groups within a lecture theatre and act as a focal point to generate conversation. Through the approach presented here core knowledge is first established and then supplemented with high level problem solving through a "Think-Pair-Share" cooperative learning strategy. The teaching delivery was adjusted based around experiential learning activities by moving the object from mental cognition and into the physical environment. This approach led to students being able to better visualise biological molecules and a positive engagement in the lecture. The use of objects in teaching allows the lecturer to create interactive sessions that both challenge and enable the student.
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Stan, Adina Dora, Codruta Birle, and Dana Slavoaca. "Biological molecules in clinical stroke trials." Romanian Journal of Neurology 12, no. 4 (December 31, 2013): 175–79. http://dx.doi.org/10.37897/rjn.2013.4.2.

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Stroke remains a leading cause of disability and mortality all over the world despite the efforts made towards improving treatment. Most of the clinical studies have not shown significant beneficial effects in the evaluation of various molecules for their neuroprotection and neuro-recovery promoting properties. The new concept of multimodal, pleiotropic drugs has opened new perspectives in this field. This review focuses on clinical stroke studies with biologically active molecules such as erythropoietin, granulocyte-colony stimulating factor and Cerebrolysin.
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Pushpanathan, Muthuirulan, Paramasamy Gunasekaran, and Jeyaprakash Rajendhran. "Antimicrobial Peptides: Versatile Biological Properties." International Journal of Peptides 2013 (June 26, 2013): 1–15. http://dx.doi.org/10.1155/2013/675391.

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Antimicrobial peptides are diverse group of biologically active molecules with multidimensional properties. In recent past, a wide variety of AMPs with diverse structures have been reported from different sources such as plants, animals, mammals, and microorganisms. The presence of unusual amino acids and structural motifs in AMPs confers unique structural properties to the peptide that attribute for their specific mode of action. The ability of these active AMPs to act as multifunctional effector molecules such as signalling molecule, immune modulators, mitogen, antitumor, and contraceptive agent makes it an interesting candidate to study every aspect of their structural and biological properties for prophylactic and therapeutic applications. In addition, easy cloning and recombinant expression of AMPs in heterologous plant host systems provided a pipeline for production of disease resistant transgenic plants. Besides these properties, AMPs were also used as drug delivery vectors to deliver cell impermeable drugs to cell interior. The present review focuses on the diversity and broad spectrum antimicrobial activity of AMPs along with its multidimensional properties that could be exploited for the application of these bioactive peptides as a potential and promising drug candidate in pharmaceutical industries.
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Cyphert, Jaime M., Carol S. Trempus, and Stavros Garantziotis. "Size Matters: Molecular Weight Specificity of Hyaluronan Effects in Cell Biology." International Journal of Cell Biology 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/563818.

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Hyaluronan signaling properties are unique among other biologically active molecules, that they are apparently not influenced by postsynthetic molecular modification, but by hyaluronan fragment size. This review summarizes the current knowledge about the generation of hyaluronan fragments of different size and size-dependent differences in hyaluronan signaling as well as their downstream biological effects.
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Fotopoulos, Ioannis, and Dimitra Hadjipavlou-Litina. "Hybrids of Coumarin Derivatives as Potent and Multifunctional Bioactive Agents: A Review." Medicinal Chemistry 16, no. 3 (April 17, 2020): 272–306. http://dx.doi.org/10.2174/1573406415666190416121448.

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Background: Coumarins exhibit a plethora of biological activities, e.g. antiinflammatory and anti-tumor. Molecular hybridization technique has been implemented in the design of novel coumarin hybrids with several bioactive groups in order to obtain molecules with better pharmacological activity and improved pharmacokinetic profile. Objective: Therefore, we tried to gather as many as possible biologically active coumarin hybrids referred in the literature till now, to delineate the structural characteristics in relation to the activities and to have a survey that might help the medicinal chemists to design new coumarin hybrids with drug-likeness and varied bioactivities. Results: The biological activities of the hybrids in most of the cases were found to be different from the biological activities presented by the parent coumarins. The results showed that the hybrid molecules are more potent compared to the standard drugs used in the evaluation experiments. Conclusion: Conjugation of coumarin with varied pharmacophore groups/druglike molecules responsible for different biological activities led to many novel hybrid molecules, with a multitarget behavior and improved pharmacokinetic properties.
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Dissertations / Theses on the topic "Biological Active Molecules"

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Strawbridge, Sharon Mary. "Redox-active sensors for molecules of biological interest." Thesis, University of Exeter, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414263.

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Lu, Biao. "Evaluation of physico-chemical properties of biorefinery-derived amphiphilic molecules and their effects on multi-scale biological models." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2218/document.

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Aujourd'hui, un grand nombre de nouvelles molécules peuvent être synthétisées à partir de la biomasse. Les tensioactifs dérivés de sucre sont notamment considérés comme une alternative aux tensioactifs fossiles en raison de leur biodégradabilité et de leur biocompatibilité. Cependant, les études associant la caractérisation physico-chimique et les propriétés biologiques de ce type de tensio-actifs sont limitées. Il est ainsi difficile de prédire les propriétés d'un tensioactif à partir de sa structure chimique. L'établissement d'une méthodologie permettant de relier la structure des surfactants à leurs propriétés apparait pertinent. Dans ce travail, quatre surfactants dérivés de sucre ayant chacun une chaîne C8 liée à une tête glucose ou maltose par un groupe amide ont été caractérisés par leurs propriétés tensio-actives dans différentes solutions (eau et milieu biologique). Leurs interactions avec des protéines ont également été analysées. Concernant l'évaluation des propriétés biologiques, des tests de cytotoxicité/irritation ont été effectués sur trois modèles in-vitro : 1) modèle cellulaire 20 (cellules L929 cultivées en monocouche), Il) modèle cellulaire 30 (cellules L929 cultivées dans un gel de collagène), Ill) épiderme humain reconstitué. Les résultats indiquent que les quatre surfactants synthétisés présentent de bonnes propriétés tensio-actives et trois d'entre eux sont moins cytotoxiques que des tensioactifs de référence. Plusieurs hypothèses permettant de relier la structure chimique des molécules à leurs propriétés physico-chimiques et biologiques ont été proposées. Des travaux futurs permettront d'enrichir la base de données sur les relations structure-propriétés des tensioactifs issus de la biomasse, et de l'utiliser pour synthétiser des surfactants présentant des propriétés adaptées aux applications envisagées
Nowadays, a wide variety of new molecules can derive from biomass. Among them, the family of sugar-based surfactants, which are considered as alternatives to fossil-based surfactants, due to their relatively high biodegradability and biocompatibility, exhibit interesting properties both in terms of their self-assembly and their ability to induce biological responses. In the study, for the purpose to analyse these properties, different methodologies have been established. In this work, physico-chemistry and cellular biology methodologies are associated to analyse the properties of pre-selected molecules characterized by gradua) structure modifications. Firstly, we have screened synthesized sugar-based surfactants according to their solubility and their ability to reduce surface tension of water. Four pre-selected molecules, with a C8 chain linked to a glucose or maltose head through an amide functional group, either under the form of carbamoyl (carbohydrate scaffold bearing the carbonyl) or alkylcarboxamide (the alkyl chain bearing the carbonyl), were then dissolved in water/ cell culture media for surface tension measurements. Their behaviors in solutions were characterized by Krafft points, Critical Micellar Concentrations or self-assembling properties through different methods. To evaluate the cytotoxic/ irritant effects of these molecules on cells and tissues, 3 in-vitro models were established: I) 2D cell culture mode! (L929 cell monolayer) II) 3D ce!! culture mode! (L929 cells embedded in collagen gel) and III) Reconstituted human epidermis (differentiated human keratinocytes). Corresponding experiments were carried out on these models with increasing complexity. Results show that the synthesized sugar-based surfactants, GlulamideC8, Glu6amideC8, Glu6amideC8' and MallamideC8 can reduce the surface tension of water solution to the came level as standard surfactants (Tween 20 and Hecameg). In the meantime, GlulamideC8, Glu6amideC8' and MallamideC8 present Iess cytotoxicity effects on L929 cells both in the monolayer model and the 3D mode! than Tween 20 and Hecameg. All synthesized and standard surfactants (GlulamideC8, Glu6amideC8, Gu6amideC8', MallamideC8, Tween 20 and Hecameg) have no significant cytotoxic/ irritant effects on reconstituted human epidermis at 1000 ig/mL after 48 h of topical application. Discussions have been made according to the results of experiments to establish possible structures/ physico-chemical properties - cytotoxicity relationships of these surfactants
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Shortt, Marie Fiona. "Synthetic approaches to biologically active molecules." Thesis, Bangor University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282267.

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Finn, P. W. "Computer studies on biologically active molecules." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374793.

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d'Ippolito, Giuliana. "Biologically active molecules from marine microalgae." Thesis, Open University, 2005. http://oro.open.ac.uk/54203/.

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Diatoms are unicellular photosynthetic microalgae responsible for approximately 40% of marine primary productivity. This algal class has traditionally been regarded as providing the bulk of the food that sustains the marine food chain to top consumers and important fisheries. However, this beneficial role has recently been questioned on the basis of laboratory and field studies showing that although dominant zooplankton grazers such as copepods feed extensively on diatoms, the hatching success of eggs thus produced is seriously impaired. Short chain polyunsaturated aldehydes, such as 2,4,7-decatrienal and 2,4-decadienal, were correlated to the antiproliferative effect of diatoms on copepod reproduction. After establishing a method of analysis, the aldehyde profile of some ecologically relevant species of marine diatoms was assessed. The results showed that the production of aldehydes is species-specific. Detailed chemical analysis revealed the presence of fatty acid derivatives other than aldehydes such as hydroxyacids, ketoacids, oxoacids and epoxyalcohols, increasing the complexity of a chemical defence of diatoms mediated only by aldehydes. All these compounds belong to a class of compounds called oxylipins, that are oxygenated compounds biosynthesized from fatty acids by oxygenasecatalyzed oxygenation. Marine diatoms are able to produce the major antiproliferative oxylipins by a novel oxygenase-dependent oxidation of C16 fatty acids hexadecatrienoic acid (16:3 (w-4)) and hexadecatetrenoic acid (16:4 (w-1)), and C2o eicosapentaenoic acid (20:5 (w-3)). This process is triggered by lypolitic acyl hydrolase activity, that feeds the downstream lipoxygenase pathway. The ecological meaning of the oxylipin pathway in the diatom-copepod interactions is discussed, showing that attention should move from single compounds to complex biochemical process. The deleterious effect on copepod reproduction could be due to a biochemical process such as the generation of an high oxidative potential, rather than only by aldehydes or other secondary oxygenated products, that when present can co-occur to produce the final effect.
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Tunbridge, Gemma Ann. "Efficient synthesis of biologically active small molecules." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.571862.

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Pancratistatin and narciclasine are natural products isolated from Pancratium litorale1 and Narcissus poeticus2 respectively. Pancratistatin and Narciclasine have been shown to possess potent antitumour activity3 however they have never been widely exploited due to their limited availability from natural sources.4 Pancratistatin and narciclasine both contain a dihydroisoquinolinone framework. The work described in this thesis explores synthetic routes relating to this dihydroisoquinolinone framework, as well as comparable tetrahydroisoquinolines. An initial proposed synthetic route involved the synthesis of the dihydroisoquinolinone framework via the corresponding indanone. Indanones have also been shown to possess potential antitumour activity.5 A range of lactam and indanone analogues were synthesised and a selection were tested for biological activity against cancer cell lines. The most biologically active lactam analogue synthesised was lactam 170. Lactam 170 was synthesised via two steps from commercially available starting materials in an overall 51 % yield and was tested in the HT29 colon cancer cell line to give an IC50 value of 9 μM. Indanone 177 is an analogue of natural product indanocine and was synthesised via two steps in an overall 49 % yield. Analogue 177 was tested in the 60 cell line screen by the National Cancer Institute (NCI) to give a mean GI50 value of 1.29 μM and is currently under consideration for further testing. This thesis describes the synthesis and biological testing of the aforementioned compounds as well as an array of analogues.
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Gutierrez, Mauricio R. (Mauricio Roberto). "Size adjustable separation of biologically active molecules." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/34150.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (p. 92-96).
Separation of biologically active molecules (BAM's) is a problem for the pharmaceutical and biotechnology industries. Current technologies addressing this problem require too many techniques, toxic additives, and time to filter desired materials. As a result, a new technology is needed. The objective of this thesis is to contribute towards the development of a new method for separating biologically active molecules in the size range of 0.5 nanometers to 500 nanometers. A normally open diaphragm valve is proposed that can control a gap formed by two flat surfaces. For accurate control of gap height, the valve was designed to ensure that the flat surfaces remain parallel during operation . Modularity was also part of design considerations to address issues of eventual biocompatibility breakdown specifically protein adsorption. Control of the gap has been achieved to increments of 1.8 nanometers.
by Mauricio R. Gutierrez.
S.M.
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Perez-Powell, Isabel Rose. "From fragments of prostanoids to biologically active molecules." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.707737.

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Jiang, Xiaohui. "Computational and NMR studies of biologically active molecules /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9906482.

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Muller, Christophe. "The synthesis of biologically active molecules using organocobalt complexes." Thesis, Kingston University, 1997. http://eprints.kingston.ac.uk/20608/.

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Books on the topic "Biological Active Molecules"

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Schlunegger, Urs Peter, ed. Biologically Active Molecules. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74582-9.

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Mahapatra, Debarshi Kar, and Sanjay Kumar Bharti. Biologically Active Small Molecules. New York: Apple Academic Press, 2022. http://dx.doi.org/10.1201/9781003283119.

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Brenna, Elisabetta, ed. Synthetic Methods for Biologically Active Molecules. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527665785.

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Hiroyasu, Aizawa, ed. Metabolic maps: Pesticides, environmentally relevant molecules, and biologically active molecules. San Diego, Calif: Academic Press, 2001.

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Necib, Y. Biochemical evaluation of lectins and other biologically active molecules. Salford: University of Salford, 1987.

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Ion-exchange sorption and preparative chromatography of biologically active molecules. New York: Consultants Bureau, 1986.

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Samsonov, G. V. Ion-Exchange Sorption and Preparative Chromatography of Biologically Active Molecules. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-8908-8.

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NATO Advanced Research Workshop on Molecular and Cellular Mechanisms of H [plus] transport (1993 York, England). Molecular and cellular mechanisms of H [plus] transport. Berlin: Springer-Verlag, 1994.

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P, Schlunegger Urs, and Schweizerischer Chemiker-Verband, eds. Biologically active molecules: Identification, characterization, and synthesis : proceedings of a Seminar on Chemistry on Biologically Active Compounds and Modern Analytical Methods, Interlaken, September 5-7, 1988. Berlin: Springer-Verlag, 1989.

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International, Symposium on Molecular Basis of Biomembrane Transport (1988 Bari Italy). Molecular basis of biomembrane transport: Proceedings of the International Symposium on Molecular Basis of Biomembrane Transport, Bari, Italy, 30 May-2 June 1988. Amsterdam: Elsevier, 1988.

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Book chapters on the topic "Biological Active Molecules"

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Anke, Timm, and Wolfgang Steglich. "β-Methoxyacrylate Antibiotics: From Biological Activity to Synthetic Analogues." In Biologically Active Molecules, 9–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74582-9_2.

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Caprioli, Richard M. "Coupling Chromatographic Techniques with FABMS for the Structural Analysis of Biological Compounds." In Biologically Active Molecules, 79–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74582-9_6.

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Chhajed, Santosh S., Virupaksha A. Bastikar, Pramodkumar P. Gupta, and Shital Chaskar. "Biological Databases: Tool for Low Molecular Weight Ligand Discovery Process." In Biologically Active Small Molecules, 247–57. New York: Apple Academic Press, 2022. http://dx.doi.org/10.1201/9781003283119-13.

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Jasiobędzki, W., and J. Woźniak-Kornacka. "Diphenylmethylenechlorocyclosulfone a New Biologically Active System." In Spectroscopy of Biological Molecules: Modern Trends, 631–32. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5622-6_287.

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Miškovský, P., D. Jancura, E. Kočišová, S. Sánchez-Cortés, F. Sureau, and L. Chinsky. "Hypericin — an Antiretroviral and Antineoplastic Active Agent:." In Spectroscopy of Biological Molecules: Modern Trends, 377–78. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5622-6_168.

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Czernuszewicz, R. S., G. Fraczkiewicz, R. Fraczkiewicz, B. C. Dave, and J. P. Germanas. "Ground and Excited State Dynamics of Blue Cu Active Site from Resonance Raman Spectroscopy of Azurin." In Spectroscopy of Biological Molecules, 273–76. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0371-8_122.

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Fahmy, K., F. Siebert, and T. P. Sakmar. "Molecular Determinants of the Active Conformation of Rhodopsin Studied by Attenuated Total Reflectance FTIR Difference Spectroscopy." In Spectroscopy of Biological Molecules, 171–72. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0371-8_77.

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Maskevich, S., I. Sveklo, A. Feofanov, A. Ianoul, V. Oleinikov, O. Fedorova, S. Gromov, I. Nabiev, M. Alfimov, and L. Kivach. "Annealing of Glass-Deposited Silver Island Films Lead to Creation of Regular Sers-Active Surfaces. Comparative Scanning Tunnel Microscopy and Sers Study." In Spectroscopy of Biological Molecules, 27–28. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0371-8_11.

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Gdalevsky, G. Y., T. Erez, D. Gill, Y. M. Torchinsky, and A. H. Parola. "High Photosensitivity of the Active Site- Bound Pyridoxal Phosphate in Tryptophanase." In Spectroscopy of Biological Molecules: Modern Trends, 183–84. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5622-6_82.

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Stanishevsky, Ivan V., and Konstantin N. Solovyov. "Direct determination of the photochemically active electronic state by optical spectroscopy methods." In Spectroscopy of Biological Molecules: New Directions, 135–36. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4479-7_57.

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Conference papers on the topic "Biological Active Molecules"

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Shim, Youn Young, Timothy Tse, and Martin Reaney. "Biological Activities of Flaxseed Peptides (Linusorbs)." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/zrcc3198.

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Flaxseed (Linum usitatissimum >L.) is gaining popularity in the food industry as a superfood due to its health-promoting properties. The flax plant synthesizes an array of biologically active cyclic peptides or linusorbs (LOs, a.k.a. cyclolinopeptides) from three or more ribosome-derived precursors. [1–9-NαC]-linusorb B3 and [1–9-NαC]-linusorb B2, suppress immunity, induce apoptosis in human epithelial cancer cell line (Calu-3) cells, and inhibit T-cell proliferation, but the mechanism of LOs action is unknown. Using gene expression analysis in nematode cultures and human cancer cell lines we have observed that LOs exert their activity, in part, through induction of apoptosis. Specific LOs’ properties include: 1) distribute throughout the body after flaxseed consumption; 2) induce heat shock protein (HSP) 70A production as an indicator of stress and addressed the issue in Caenorhabditis elegans (exposure of nematode cultures to [1–9-NαC]-linusorb B3 induced a 30% increase in production of the HSP 70A protein); 3) induce apoptosis in Calu-3 cells; and 4) modulate regulatory genes in microarray analysis. These diverse activities indicate that LOs might induce apoptosis in cancer cells or act as versatile platforms to deliver a variety of biologically active molecules for cancer therapy.
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Sarles, Stephen A., Pegah Ghanbari Bavarsad, and Donald J. Leo. "Incorporation and characterization of biological molecules in droplet-interface bilayer networks for novel active systems." In SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, edited by Mehdi Ahmadian and Mehrdad N. Ghasemi-Nejhad. SPIE, 2009. http://dx.doi.org/10.1117/12.815846.

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Grattoni, Alessandro, Xuewu Liu, Zongxing Wang, Jaskaran Gill, Arturas Ziemys, and Mauro Ferrari. "Electrokinetic Transport of Molecules Through Nanochanneled Membranes." In ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13236.

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Our research group was the first one to microfabricate and demonstrate nano-channels in silicon membranes (1, 2). We employed nano-channeled chips to provide immuno-isolation for cell transplantation towards the treatment of diabetes (3), for biomolecular separation (4), and for the controlled passive and active release of drug molecules from implanted capsules (5). We showed that the constraints placed upon molecular agitation in nano-channels affected their concentration-driven transport kinetics (6, 7). A zero-order passive release of biological molecules was achieved, by the rational tailoring of nano-channels dimensions. This achievement allowed releasing of a constant amount of drugs over a long period of time. However, the development and optimization of many drug therapies require long-term drug delivery with controlled but variable dosage using miniaturized systems (8). Moreover, application such as drug release from implanted devices requires tight operational control, of regulatory agency caliber. We have engaged in the development and characterization of elecroosmotic nano-channels membranes, and present our results in this communication. These include the influence of the drug release rate on nanochannel size, membrane configuration, and applied voltage.
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El-Beyrouthy, Joyce, and Eric C. Freeman. "Rapid and Real-Time Measurement of Membrane Potential Through Intramembrane Field Compensation." In ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/smasis2020-2352.

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Abstract Synthetic lipid membranes are self-assembled biomolecular double layers designed to approximate the properties of living cell membranes. These membranes are employed as model systems for studying the interactions of cellular envelopes with the surrounding environment in a controlled platform. They are constructed by dispersing amphiphilic lipids into a combination of immiscible fluids enabling the biomolecules to self-assemble into ordered sheets, or monolayers at the oil-water interface. The adhesion of two opposing monolayer sheets forms the membrane, or the double layer. The mechanical properties of these synthetic membranes often differ from biological ones mainly due to the presence of residual solvent in between the leaflets. In fact, the double layer compresses in response to externally applied electrical field with an intensity that varies depending on the solvent present. While typically viewed as a drawback associated with their assembly, in this work the elasticity of the double layer is utilized to further quantify complex biophysical phenomena. The adsorption of charged molecules on the surface of a lipid bilayer is a key property to decipher biomolecule interactions at the interface of the cell membrane, as well as to develop effective antimicrobial peptides and similar membrane-active molecules. This adsorption generates a difference in the boundary potentials on either side of the membrane which may be tracked through electrophysiology. The soft synthetic membranes produced in the laboratory compress when exposed to an electric field. Tracking the minimum membrane capacitance allows for quantifying when the intrinsic electric field produced by the asymmetry is properly compensated by the supplied transmembrane voltage. The technique adopted in this work is the intramembrane field compensation (IFC). This technique focuses on the current generated by the bilayer in response to a sinusoidal voltage with a DC component, VDC. Briefly, the output sinusoidal current is divided into its harmonics and the second harmonic equals zero when VDC compensates the internal electric field. In this work, we apply the IFC technique to droplet interface bilayers (DIB) enabling the development of a biological sensor. A certain membrane elasticity is needed for accurate measurements and is tuned through the solvent selection. The asymmetric DIBs are formed, and an automated PID-controlled IFC design is implemented to rapidly track and compensate the membrane asymmetry. The closed loop system continuously reads the current and generates the corresponding voltage until the second harmonic is abated. This research describes the development and optimization of a biological sensor and examines how varying the structure of the synthetic membrane influences its capabilities for detecting membrane-environment interactions. This platform may be applied towards studying the interactions of membrane-active molecules and developing models for the associated phenomena to enhance their design.
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Šolínová, Veronika, Václav Kašička, Petra Sázelová, and Tomislav Barth. "Prediction of molecular shape and separation of structurally related GnRHs by capillary electrophoresis." In Xth Conference Biologically Active Peptides. Prague: Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 2007. http://dx.doi.org/10.1135/css200709096.

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Gutierrez, Mauricio R., and Kamal Youcef-Toumi. "Programmable Separation for Biologically Active Molecules." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14141.

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Separation of biologically active molecules (BAMs) is a problem for the pharmaceutical and biotechnology industries. Current technologies addressing this problem require too many techniques, toxic additives, and time to filter the desired materials. As a result, a new technology is needed. The objective of this work is to contribute to the development of a device that can separate 0.5 nm to 500 nm sized BAMs. A diaphragm valve is proposed that can control a gap created by two parallel flat surfaces. Position control is achieved by means of a piezoelectric actuator and a capacitive sensor. Modularity was also part of design considerations to address issues of eventual biocompatibility breakdown. Preliminary experiments indicate that gap separation can be controlled to increments of 0.2 nm.
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Dejana, E., F. Breviario, F. Bussolino, L. Mussoni, and A. Mantovani. "PLEIOTROPIC EFFECT OF INTERLEUKIN-1 ON ENDOTHELIAL CELLS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643984.

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Inflammatory processes are often associated with pathological alteration of the vessel wall and sometimes with local or disseminated thrombotic phenomena. Interleukin-1 (IL-1), a monokine produced by activated cells of the monocyte/macrophage lineage and responsible of most of the changes associated with the inflammatory acute phase response, appears to dramatically' modify several endothelial cell (EC) functions. Some groups including ours (for review 1) have shown that IL-1 stimulates prostacyclin (PGI2), platelet activating factor (PAF), plasminogen activator inhibitor (PAi), thromboplastin (PCA) synthesis by cultured human EC in vitro. In addition IL-1 can act directly on EC to increase neuthophil and other leukocyte adhesion on their surface (2). All these effects, in contrast to previously described inducers, require a long time of interaction (30 min to 4 hours) of IL-1 with EC to be apparent and then last for several hours (4 to 12 hours). The IL-1 effects are concentration dependent (minimal active concentration being about 1 unit/ml) and require protein and RNA synthesis. To better define the structural requirement for IL-1 induced modification of EC functions we compared the activity of different IL-1 molecular species. Our approach is based on the observation that IL-1 is indeed a family of polypeptides biochemically different(3). At least two dissimilar gene products have been cloned with very limited homology (denominated α and β). These molecules, though biochemically different, share common activities and possibly the same receptor in different cell types. On EC we investigated whether the αand β IL-1 forms have similar biological activities (4). All the IL-1 preparations used were active on thymocyte costimulatory assay and comparison was made on the basis of the concentrations of these agents equally active on this assay.Human recombinant IL- αandβ (hr IL-1 α and hr IL-1 β) were both active in stimulating PGI2, PCA, PAi production and in increasing neutrophil adhesion to EC. In contrast PAF synthesis was Stimulated by hr IL-1 α but not by hr IL-1 β. Murine recombinant IL-1 (mr IL-1 α highly homologous with hr IL-1 < α, at concentrations able to maximally activate thymocytes was inactive on PGI2, PCA and in increasing neutrophil adhesion to EC. In contrast, mr IL-1 α was equally effective on PAF production as hr IL-1 α. A short peptide fragment of hr IL-1β (fragment 167-171) was synthesized on the basis of its predicted exposure on the surface of the molecule (5). This peptide is also located in a region (150-186) of high homology between hr IL-1α and β sequences. While the peptide showed high thymocyte activation capacity it was inactive on EC activities. Overall these results indicate that the α and β forms of human IL-1 elicit largely but not completely overlapping patterns of response in EC. In addition they suggest that the structural requirement for activation by IL-1 is not identical for thymocytes and EC. These results might provide some clues to novel strategies for modulation of IL-1 vascular and immunological activities.1. Mantovani A. and E. Dejana (1987) Biochem. Pharm. 36:301.2. Bevilacqua M. et al. (1985) J. Clin. Invest. 76:20033. Dinarello C.A. (1985) J. Clin. Immunol. 5:287.4. Dejana E. et al. (1987) Blood 69:695.5. Antoni G. et al. (1987) J. Immunol, (in press).
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Sadik, Mohamed M., Jianbo Li, Jerry W. Shan, David I. Shreiber, and Hao Lin. "Quantifying the Effects of Extracellular Conductivity on Transport During Electroporation." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53215.

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Electroporation is an effective means to permeabilize the cell membrane and deliver biologically active molecules (such DNA, RNA, dyes, etc…) into the cell cytoplasm, while maintaining cell viability and functionality [1]. Despite extensive research, electroporation still suffers from major drawbacks such as high cell death and low delivery efficiency. In the past, studies focused mainly on permeabilization of the membrane during electroporation while transport of molecules from one side of the membrane to the other has been overlooked. Previous experimental work demonstrated an inverse relation between the electrical conductivity of the extracellular buffer and total concentration delivered into cells [2]. This inverse correlation suggests that additional molecular transport mechanisms, besides diffusion, govern the delivery into cells.
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Loskutoff, D. J., J. Mimuro, and C. Hekman. "PLASMINOGEN ACTIVATOR INHIBITOR." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644763.

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Plasminogen activation provides an important source of localized proteolytic activity not only during fibrinolysis, but also during ovulation, cell migration, epithelial cell differentiation, tumor invasion and a variety of other physiological processes. Precise regulation of plasminogen activator (PA) activity thus constitutes a critical feature of many biological processes. This control is achieved in large part through the action of specific PA inhibitors (PAIs). Although 4 distinct PAIs have been detected,1the endothelial cellTderived inhibitor (PAI-1) is the only one that efficiently inhibits both urokinase (Kd=2.3×10−13M; Kassoc =1.6×108 M−1s−1) and single-chaintissue-type PA (tPA; Kd=1.3×lO−15 M Kd=3.9×lO7M−1s−1). It also inhibits trypsin (Kassoc=6.8×106M−1 s−1 ) ancl Plasmin (Kassoc=7.6×l05 M−1 s5 Analysis of the effect of PAI-1 on the rate of plasminogen activation revealed a competitive type of inhibition when urokinase was employed but a linear mixed type of inhibition when single chain tPA was employed. These results suggest that the interaction of PAI-1 with tPA, in contrast to its interaction with urokinase, may involve 2 sites on the tPA molecule.PAI-1 has been purified from medium conditioned by cultured bovine aortic endothelial cells and partially characterized. It is a major biosynthetic product of these cells, accounting for as much as 12% of the total protein released by the cells in 24 h. It has an M of 50,000, an isoelectric point of 4.5-5.0, and is immunologically and biochemically related to the rapidly acting inhibitor present in human platelets and in the plasma of some patients at risk to develop thrombotic problems. Although it is relatively stable to conditions which inactivate most protease inhibitors (acid pH, SDS), it is extremely sensitive to oxidants. The molecular cloning of the PAI-1 gene revealed that the mature human protein is 379 amino acids long, contains an NH2-terminal valine, lacks cysteines and has a methionine at the Pi position of it's reactive center. The conversion of this methionine to methionine sulfoxide may be responsible for the rapid inactivation of PAI-1 by oxidants. Human PAI-1 has extensive (30%) homology with α1-antitrypsin and antithrombin III and is thus a member of the serine proteinase inhibitor (serpin) family; a group of related molecules that control the major protease cascades of the blood. The PAI-1 gene is approximately 12.2 kilobase pairs in length and is organized into nine exons and eight introns.The production of PAI-1 by endothelial cells is stimulated by endotoxin, interleukin-1, tumor necrosis factor, and transforming growth factor β(TGFβ). The cells are extremely sensitive to TGFβwith maximal effects (100-fold stimulation) observed with 1-2 ng/ml. These changes were relatively specific for PAI-1, and could be detected at both the protein and the RNA level. Interestingly, TGFgalso stimulated the amount of PAI-1 present in the extracellular matrix (ECM) of BAEs. PAI-1 was one of the primary ECM components of these cells, constituting 10-20% of the ECM proteins detected after SDS-PAGE.One of the most unusual properties of PAI-1 is that it exists in blood and in various cellular samples in both an active and an inactive (latent) form, the ratio depending on the source. The latent form can be converted into the active one by treatment with denaturants like SDS or guanidine-HCl. Although the majority of the cell-associated PAI-1 is active, it rapidly decays (t1/2=3 h) into the latent form once it is released from the cells. In contrast, the half-life of ECM associated PAI-1 was greater than 24 h. These data suggest that PAI-1 is produced by BAEs in an active form, and is then either released into the medium where it is rapidly inactivated, or released into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation.
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Shumaev, K. B., O. V. Kosmachevskaya, E. I. Nasybullina, and A. F. Topunov. "THE ORIGIN AND EVOLUTION OF THE SIGNAL FUNCTION OF NITRIC OXIDE." In NOVEL TECHNOLOGIES IN MEDICINE, BIOLOGY, PHARMACOLOGY AND ECOLOGY. Institute of information technology, 2022. http://dx.doi.org/10.47501/978-5-6044060-2-1.247-251.

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The article discusses the evolutionary aspects of the functioning of nitric oxide (NO) in various organisms. As a signaling molecule, NO is widely distributed in both prokaryotes and eukar-yotes. The diverse action of NO is due to the formation of its biologically active metabolites. The formation of these NO derivatives was associated with the evolution of energy homeosta-sis and protection of living systems from oxidative stress.
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Reports on the topic "Biological Active Molecules"

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Kapulnik, Yoram, and Donald A. Phillips. Isoflavonoid Regulation of Root Bacteria. United States Department of Agriculture, January 1996. http://dx.doi.org/10.32747/1996.7570561.bard.

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The overall objective of this project was to develop a conceptual framework for enhancing root colonization by beneficial bacteria. To accomplish this aim we tested the hypothesis that production and excretion of the plant phytoalexin medicarpin can be used for creation of a special niche along the legume roots, where beneficial microorganism, such as rhizobium, will have a selective advantage. On the Israeli side it was shown that higher medicarpin levels are exuded following the application of Rhizobium meliloti to the rhizosphere but the specific biochemical pathway governing medicarpin production was not induced significantly enough to support a constant production and excretion of this molecule to the rhizosphere. Furthermore, pathogenic bacteria and chemical elicitors were found to induce higher levels of this phytoalexin and it became important to test its natural abundance in field grown plants. On the US side, the occurrence of flavonoids and nucleosides in agricultural soils has been evaluated and biologically significant quantities of these molecules were identified. A more virulent Agrobacterium tumefaciens strain was isolated from alfalfa (Medicago sativa L.) which forms tumors on a wide range of plant species. This isolate contains genes that increase competitive colonization abilities on roots by reducing the accumulation of alfalfa isoflavonoids in the bacterial cells. Following gene tagging efforts the US lab found that mutation in the bacterial efflux pump operons of this isolate reduced its competitive abilities. This results support our original hypothesis that detoxification activity of isoflavenoids molecules, based on bacterial gene(s), is an important selection mechanism in the rhizosphere. In addition, we focused on biotin as a regulatory element in the rhizosphere to support growth of some rhizosphere microorganisms and designed a bacterial gene construct carrying the biotin-binding protein, streptavidin. Expressing this gene in tobacco roots did not affect the biotin level but its expression in alfalfa was lethal. In conclusion, the collaborative combination of basic and applied approaches toward the understanding of rhizosphere activity yielded new knowledge related to the colonization of roots by beneficial microorganisms in the presence of biological active molecules exuded from the plant roots.
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López-Valverde, Nansi, Javier Aragoneses, Antonio López-Valverde, Cinthia Rodríguez, and Juan Manuel Aragoneses. Role in the osseointegration of titanium dental implants, of bioactive surfaces based on biomolecules: A systematic review and meta-analysis of in vivo studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, June 2022. http://dx.doi.org/10.37766/inplasy2022.6.0076.

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Review question / Objective: Does the bioactive surface of titanium dental implants, based on biomolecules, influence osseointegration?. The aim of our study was to evaluate the role and efficacy of bioactive surfaces in osseointegration. Our review study limited the research interest to titanium dental implants coated with a biomolecule, i.e., an organic molecule produced by a living organism. Condition being studied: In recent years, much attention has been paid to topographical modifications of dental implant surfaces, as well as to their coating with biologically active substances.a bioactive surface is one capable of achieving faster and higher quality osseointegration, shortening waiting times and solving situations of poor bone quality. Molecules that can be applied for bioactive purposes include bioceramics, ions and biomolecules. Collagen and bone morphogenetic protein have been suggested as bone stimulating agents. Biofunctionalization of the implant surface with a biomimetic active peptide has also been shown to result in a significant increase in bone-to-implant ratios and an increase in peri-implant bone density.
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Avni, Adi, and Gitta L. Coaker. Proteomic investigation of a tomato receptor like protein recognizing fungal pathogens. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600030.bard.

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Maximizing food production with minimal negative effects on the environment remains a long-term challenge for sustainable food production. Microbial pathogens cause devastating diseases, minimizing crop losses by controlling plant diseases can contribute significantly to this goal. All plants possess an innate immune system that is activated after recognition of microbial-derived molecules. The fungal protein Eix induces defense responses in tomato and tobacco. Plants recognize Eix through a leucine-rich-repeat receptor- like-protein (LRR-RLP) termed LeEix. Despite the knowledge obtained from studies on tomato, relatively little is known about signaling initiated by RLP-type immune receptors. The focus of this grant proposal is to generate a foundational understanding of how the tomato xylanase receptor LeEix2 signals to confer defense responses. LeEix2 recognition results in pattern triggered immunity (PTI). The grant has two main aims: (1) Isolate the LeEix2 protein complex in an active and resting state; (2) Examine the biological function of the identified proteins in relation to LeEix2 signaling upon perception of the xylanase elicitor Eix. We used two separate approaches to isolate receptor interacting proteins. Transgenic tomato plants expressing LeEix2 fused to the GFP tag were used to identify complex components at a resting and activated state. LeEix2 complexes were purified by mass spectrometry and associated proteins identified by mass spectrometry. We identified novel proteins that interact with LeEix receptor by proteomics analysis. We identified two dynamin related proteins (DRPs), a coiled coil – nucleotide binding site leucine rich repeat (SlNRC4a) protein. In the second approach we used the split ubiquitin yeast two hybrid (Y2H) screen system to identified receptor-like protein kinase At5g24010-like (SlRLK-like) (Solyc01g094920.2.1) as an interactor of LeEIX2. We examined the role of SlNRC4a in plant immunity. Co-immunoprecipitation demonstrates that SlNRC4a is able to associate with different PRRs. Physiological assays with specific elicitors revealed that SlNRC4a generally alters PRR-mediated responses. SlNRC4a overexpression enhances defense responses while silencing SlNRC4 reduces plant immunity. We propose that SlNRC4a acts as a non-canonical positive regulator of immunity mediated by diverse PRRs. Thus, SlNRC4a could link both intracellular and extracellular immune perception. SlDRP2A localizes at the plasma membrane. Overexpression of SlDRP2A increases the sub-population of LeEIX2 inVHAa1 endosomes, and enhances LeEIX2- and FLS2-mediated defense. The effect of SlDRP2A on induction of plant immunity highlights the importance of endomembrane components and endocytosis in signal propagation during plant immune . The interaction of LeEIX2 with SlRLK-like was verified using co- immunoprecipitation and a bimolecular fluorescence complementation assay. The defence responses induced by EIX were markedly reduced when SlRLK-like was over-expressed, and mutation of slrlk-likeusing CRISPR/Cas9 increased EIX- induced ethylene production and SlACSgene expression in tomato. Co-expression of SlRLK-like with different RLPs and RLKs led to their degradation, apparently through an endoplasmic reticulum-associated degradation process. We provided new knowledge and expertise relevant to expression of specific be exploited to enhance immunity in crops enabling the development of novel environmentally friendly disease control strategies.
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Tzfira, Tzvi, Michael Elbaum, and Sharon Wolf. DNA transfer by Agrobacterium: a cooperative interaction of ssDNA, virulence proteins, and plant host factors. United States Department of Agriculture, December 2005. http://dx.doi.org/10.32747/2005.7695881.bard.

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Agrobacteriumtumefaciensmediates genetic transformation of plants. The possibility of exchanging the natural genes for other DNA has led to Agrobacterium’s emergence as the primary vector for genetic modification of plants. The similarity among eukaryotic mechanisms of nuclear import also suggests use of its active elements as media for non-viral genetic therapy in animals. These considerations motivate the present study of the process that carries DNA of bacterial origin into the host nucleus. The infective pathway of Agrobacterium involves excision of a single-stranded DNA molecule (T-strand) from the bacterial tumor-inducing plasmid. This transferred DNA (T-DNA) travels to the host cell cytoplasm along with two virulence proteins, VirD2 and VirE2, through a specific bacteriumplant channel(s). Little is known about the precise structure and composition of the resulting complex within the host cell and even less is known about the mechanism of its nuclear import and integration into the host cell genome. In the present proposal we combined the expertise of the US and Israeli labs and revealed many of the biophysical and biological properties of the genetic transformation process, thus enhancing our understanding of the processes leading to nuclear import and integration of the Agrobacterium T-DNA. Specifically, we sought to: I. Elucidate the interaction of the T-strand with its chaperones. II. Analyzing the three-dimensional structure of the T-complex and its chaperones in vitro. III. Analyze kinetics of T-complex formation and T-complex nuclear import. During the past three years we accomplished our goals and made the following major discoveries: (1) Resolved the VirE2-ssDNA three-dimensional structure. (2) Characterized VirE2-ssDNA assembly and aggregation, along with regulation by VirE1. (3) Studied VirE2-ssDNA nuclear import by electron tomography. (4) Showed that T-DNA integrates via double-stranded (ds) intermediates. (5) Identified that Arabidopsis Ku80 interacts with dsT-DNA intermediates and is essential for T-DNA integration. (6) Found a role of targeted proteolysis in T-DNA uncoating. Our research provide significant physical, molecular, and structural insights into the Tcomplex structure and composition, the effect of host receptors on its nuclear import, the mechanism of T-DNA nuclear import, proteolysis and integration in host cells. Understanding the mechanical and molecular basis for T-DNA nuclear import and integration is an essential key for the development of new strategies for genetic transformation of recalcitrant plant species. Thus, the knowledge gained in this study can potentially be applied to enhance the transformation process by interfering with key steps of the transformation process (i.e. nuclear import, proteolysis and integration). Finally, in addition to the study of Agrobacterium-host interaction, our research also revealed some fundamental insights into basic cellular mechanisms of nuclear import, targeted proteolysis, protein-DNA interactions and DNA repair.
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Gurevitz, Michael, Michael E. Adams, and Boaz Shaanan. Structural Elements and Neuropharmacological Features Involved in the Insecticidal Properties of an Alpha Scorpion Neurotoxin: A Multidisciplinary Approach. United States Department of Agriculture, August 1995. http://dx.doi.org/10.32747/1995.7573061.bard.

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Integrated pest management in modern crop protection requires the use of chemical or biological insecticides in many instances. Nontheless, the use non-selective chemical insecticides poses risks to the environment and livestock and consequently urgent need exists for safer alternatives, which target insects more specifically. Scorpions produce anti-insect selective polypeptide toxins that are biodegradable and not toxic to wam-blooded animals. Therefore, mobilization of these substances into insect pest targets is of major interest. Moreover, clarification of the molecular basis of this selectivity may provide valuable information pertinent to their receptor sites and to the future design of peptidomimetic anti-insect specific substances. These toxins may also be important for reducing the current overuse of chamical insecticides provided they have a synergistic effect with conventional pesticides. All of these objectives were addressed in this research. A direct approach for plant protection was the mobilization of toxins into target pests using baculoviral vectors. The other approach was to develop a suitable system enabling the elucidation of the toxin bioactive site, which would enable design of insecticidal peptidomimetics. In parallel, the mode of action and synergistic effects of scorpion insecticidal toxins, were studied at the sodium channel receptor site. All the above approaches show great promise and clearly indicate that scorpion insecticidal toxins may provide powerful means in insect pest control.
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Barefoot, Susan F., Bonita A. Glatz, Nathan Gollop, and Thomas A. Hughes. Bacteriocin Markers for Propionibacteria Gene Transfer Systems. United States Department of Agriculture, June 2000. http://dx.doi.org/10.32747/2000.7573993.bard.

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The antibotulinal baceriocins, propionicin PLG-1 and jenseniin G., were the first to be identified, purified and characterized for the dairy propionibaceria and are produced by Propionibacterium thoenii P127 and P. thoenii/jensenii P126, respectively. Objectives of this project were to (a) produce polyclonal antibodies for detection, comparison and monitoring of propionicin PLG-1; (b) identify, clone and characterize the propionicin PLG-1 (plg-1) and jenseniin G (jnG) genes; and (3) develop gene transfer systems for dairy propionibacteria using them as models. Polyclonal antibodies for detection, comparison and monitoring of propionicin PLG-1 were produced in rabbits. Anti-PLG-1 antiserum had high titers (256,000 to 512,000), neutralized PLG-1 activity, and detected purified PLG-1 at 0.10 mg/ml (indirect ELISA) and 0.033 mg/ml (competitive indirect ELISA). Thirty-nine of 158 strains (most P. thoenii or P. jensenii) yielded cross-reacting material; four strains of P. thoenii, including two previously unidentified bacteriocin producers, showed biological activity. Eight propionicin-negative P127 mutants produced neither ELISA response nor biological activity. Western blot analyses of supernates detected a PLG-1 band at 9.1 kDa and two additional protein bands with apparent molecular weights of 16.2 and 27.5 kDa. PLG-1 polyclonal antibodies were used for detection of jenseniin G. PLG-1 antibodies neutralized jenseniin G activity and detected a jenseniin G-sized, 3.5 kDa peptide. Preliminary immunoprecipitation of crude preparations with PLG-1 antibodies yielded three proteins including an active 3-4 kDa band. Propionicin PLG-1 antibodies were used to screen a P. jensenii/thoenii P126 genomic expression library. Complete sequencing of a cloned insert identified by PLG-1 antibodies revealed a putative response regulator, transport protein, transmembrane protein and an open reading frame (ORF) potentially encoding jenseniin G. PCR cloning of the putative plg-1 gene yielded a 1,100 bp fragment with a 355 bp ORF encoding 118 amino acids; the deduced N-terminus was similar to the known PLG-1 N-terminus. The 118 amino acid sequence deduced from the putative plg-1 gene was larger than PLG-1 possibly due to post-translational processing. The product of the putative plg-1 gene had a calculated molecular weight of 12.8 kDa, a pI of 11.7, 14 negatively charged residues (Asp+Glu) and 24 positively charged residues (Arg+Lys). The putative plg-1 gene was expressed as an inducible fusion protein with a six-histidine residue tag. Metal affinity chromatography of the fused protein yielded a homogeneous product. The fused purified protein sequence matched the deduced putative plg-1 gene sequence. The data preliminarily suggest that both the plg-1 and jnG genes have been identified and cloned. Demonstrating that antibodies can be produced for propionicin PLG-1 and that those antibodies can be used to detect, monitor and compare activity throughout growth and purification was an important step towards monitoring PLG-1 concentrations in food systems. The unexpected but fortunate cross-reactivity of PLG-1 antibodies with jenseniin G led to selective recovery of jenseniin G by immunoprecipitation. Further refinement of this separation technique could lead to powerful affinity methods for rapid, specific separation of the two bacteriocins and thus facilitate their availability for industrial or pharmaceutical uses. Preliminary identification of genes encoding the two dairy propionibacteria bacteriocins must be confirmed; further analysis will provide means for understanding how they work, for increasing their production and for manipulating the peptides to increase their target species. Further development of these systems would contribute to basic knowledge about dairy propionibacteria and has potential for improving other industrially significant characteristics.
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Kanner, Joseph, Mark Richards, Ron Kohen, and Reed Jess. Improvement of quality and nutritional value of muscle foods. United States Department of Agriculture, December 2008. http://dx.doi.org/10.32747/2008.7591735.bard.

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Food is an essential to our existence but under certain conditions it could become the origin to the accumulative health damages. Technological processes as heating, chopping, mincing, grounding, promote the lipid oxidation process in muscle tissues and meat foodstuffs. Lipid oxidation occurred rapidly in turkey muscle, intermediate in duck, and slowest in chicken during frozen storage. Depletion of tocopherol during frozen storage was more rapid in turkey and duck compared to chicken. These processes developed from lipid peroxides produce many cytotoxic compounds including malondialdehyde (MDA). The muscle tissue is further oxidized in stomach conditions producing additional cytotoxic compounds. Oxidized lipids that are formed during digestion of a meal possess the potential to promote reactions that incur vascular diseases. A grape seed extract (1% of the meat weight) and butylated hydroxytoluene (0.2% of the lipid weight) were each effective at preventing formation of lipid oxidation products for 3 hours during co-incubation with cooked turkey meat in simulated gastric fluid (SGF). Polyphenols in the human diet, as an integral part of the meal prevent the generation and absorption of cytotoxic compounds and the destruction of essential nutrients, eg. antioxidants vitamins during the meal. Polyphenols act as antioxidants in the gastrointestinal tract; they scavenge free radicals and may interact with reactive carbonyls, enzymes and proteins. These all reactions results in decreasing the absorption of reactive carbonyls and possible other cytotoxic compounds into the plasma. Consumptions of diet high in fat and red meat are contributory risk factors partly due to an increase production of cytotoxic oxidized lipid products eg. MDA. However, the simultaneously consumption of polyphenols rich foods reduce these factors. Locating the biological site of action of polyphenols in the in the gastrointestinal tract may explain the paradox between the protective effect of a highly polyphenols rich diet and the low bioavailability of these molecules in human plasma. It may also explain the "French paradox" and the beneficial effect of Mediterranean and Japanese diets, in which food products with high antioxidants content such as polyphenols are consumed during the meal.
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8

Gurevitz, Michael, Michael E. Adams, Boaz Shaanan, Oren Froy, Dalia Gordon, Daewoo Lee, and Yong Zhao. Interacting Domains of Anti-Insect Scorpion Toxins and their Sodium Channel Binding Sites: Structure, Cooperative Interactions with Agrochemicals, and Application. United States Department of Agriculture, December 2001. http://dx.doi.org/10.32747/2001.7585190.bard.

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Integrated pest management in modern crop protection may combine chemical and biological insecticides, particularly due to the risks to the environment and livestock arising from the massive use of non-selective chemicals. Thus, there is a need for safer alternatives, which target insects more specifically. Scorpions produce anti-insect selective polypeptide toxins that are biodegradable and non-toxic to warm-blooded animals. Therefore, integration of these substances into insect pest control strategies is of major importance. Moreover, clarification of the molecular basis of this selectivity may provide valuable information pertinent to their receptor sites and to the future design of peptidomimetic anti-insect specific substances. These toxins may also be important for reducing the current overuse of chemical insecticides if they produce a synergistic effect with conventional pesticides. Based on these considerations, our major objectives were: 1) To elucidate the three-dimensional structure and toxic-site of scorpion excitatory, "depressant, and anti-insect alpha toxins. 2) To obtain an initial view to the sodium channel recognition sites of the above toxins by generating peptide decoys through a phage display system. 3) To investigate the synergism between toxins and chemical insecticides. Our approach was to develop a suitable expression system for toxin production in a recombinant form and for elucidation of toxin bioactive sites via mutagenesis. In parallel, the mode of action and synergistic effects of scorpion insecticidal toxins with pyrethroids were studied at the sodium channel level using electrophysiological methods. Objective 1 was achieved for the alpha toxin, LqhaIT Zilberberg et al., 1996, 1997; Tugarinov et al., 1997; Froy et al., 2002), and the excitatory toxin, Bj-xtrIT (Oren et al., 1998; Froy et al., 1999; unpublished data). The bioactive surface of the depressant toxin, LqhIT2, has been clarified and a crystal of the toxin is now being analyzed (unpublished). Objective 2 was not successful thus far as no phages that recognize the toxins were obtained. We therefore initiated recently an alternative approach, which is introduction of mutations into recombinant channels and creation of channel chimeras. Objective 3 was undertaken at Riverside and the results demonstrated synergism between LqhaIT or AaIT and pyrethroids (Lee et al., 2002). Furthermore, negative cross-resistance between pyrethroids and scorpion toxins (LqhaIT and AaIT) was demonstrated at the molecular level. Although our study did not yield a product, it paves the way for future design of selective pesticides by capitalizing on the natural competence of scorpion toxins to distinguish between sodium channels of insects and vertebrates. We also show that future application of anti-insect toxins may enable to decrease the amounts of chemical pesticides due to their synergism.
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