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Search Results: 1 - 10 of 1111 matches for " biotechnological applications "
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Bioprospection of marine microorganisms: biotechnological applications and methods
Dionisi,Hebe M; Lozada,Mariana; Olivera,Nelda L.;
Revista argentina de microbiolog?-a , 2012,
Abstract: environmental microorganisms constitute an almost inexhaustible reserve of genetic and functional diversity, accumulated during millions of years of adaptive evolution to various selective pressures. in particular, the extent of microbial biodiversity in marine habitats seems to grow larger as new techniques emerge to measure it. this has resulted in novel and more complex approaches for the screening of molecules and activities of biotechnological interest in these environments. in this review, we explore the different partially overlapping biotechnological fields that make use of microorganisms and we describe the different marine habitats that are particularly attractive for bioprospection. in addition, we review the methodological approaches currently used for microbial bioprospection, from the traditional cultivation techniques to state of the art metagenomic approaches, with emphasis in the marine environment.
Halogenated Compounds from Marine Algae
Maria Teresa Cabrita,Carlos Vale,Amélia Pilar Rauter
Marine Drugs , 2010, DOI: 10.3390/md8082301
Abstract: Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds.
Brown Spider (Loxosceles genus) Venom Toxins: Tools for Biological Purposes
Olga Meiri Chaim,Dilza Trevisan-Silva,Daniele Chaves-Moreira,Ana Carolina M. Wille,Valéria Pereira Ferrer,Fernando Hitomi Matsubara,Oldemir Carlos Mangili,Rafael Bertoni da Silveira,Luiza Helena Gremski,Waldemiro Gremski,Andrea Senff-Ribeiro,Silvio Sanches Veiga
Toxins , 2011, DOI: 10.3390/toxins3030309
Abstract: Venomous animals use their venoms as tools for defense or predation. These venoms are complex mixtures, mainly enriched of proteic toxins or peptides with several, and different, biological activities. In general, spider venom is rich in biologically active molecules that are useful in experimental protocols for pharmacology, biochemistry, cell biology and immunology, as well as putative tools for biotechnology and industries. Spider venoms have recently garnered much attention from several research groups worldwide. Brown spider (Loxosceles genus) venom is enriched in low molecular mass proteins (5–40 kDa). Although their venom is produced in minute volumes (a few microliters), and contain only tens of micrograms of protein, the use of techniques based on molecular biology and proteomic analysis has afforded rational projects in the area and permitted the discovery and identification of a great number of novel toxins. The brown spider phospholipase-D family is undoubtedly the most investigated and characterized, although other important toxins, such as low molecular mass insecticidal peptides, metalloproteases and hyaluronidases have also been identified and featured in literature. The molecular pathways of the action of these toxins have been reported and brought new insights in the field of biotechnology. Herein, we shall see how recent reports describing discoveries in the area of brown spider venom have expanded biotechnological uses of molecules identified in these venoms, with special emphasis on the construction of a cDNA library for venom glands, transcriptome analysis, proteomic projects, recombinant expression of different proteic toxins, and finally structural descriptions based on crystallography of toxins.
Marine metagenomics, a valuable tool for enzymes and bioactive compounds discovery
Pietro Tedesco,Donatella De Pascale
Frontiers in Marine Science , 2014, DOI: 10.3389/fmars.2014.00038
Abstract: The enormous potential in diversity of the marine life is still not fully exploited due to the difficulty in culturing many of the microorganisms under laboratory conditions. In this mini-review we underlined the importance of using an omics technique, such as metagenomics, to access the uncultured majority of microbial communities. We report examples of several hydrolytic enzymes and natural products isolated by functional sequenced-based and function- screening strategies assisted by new high-throughput DNA sequencing technology and recent bioinformatics tools. This article ends with an overview of the potential future perspectives of the metagenomics in bioprospecting novel biocatalysts and bioactive compounds from marine sources.
Purification and Some Properties of Thermo-stable Alkaline Serine Protease from Thermophilic Bacillus sp. Gs-3
U.O. George-Okafor,F.J.C. Odibo
Journal of Biological Sciences , 2011,
Abstract: There are limited reliable information on the commercial production and utilization of proteases for detergent and other industrial uses in Nigeria. Hence, the purification and characterization of Bacillus sp. Gs-3 protease for its potential industrial uses were investigated. The dialyzed crude enzyme was purified 17-fold in a two-step procedure involving carboxymethyl sepharose ionic-exchange chromatography and phenyl sepharose 6-fast flow hydrophobic interaction chromatography. The purified enzyme had its optimal activity at pH 9.0 and 90C and was stable over a pH range 8.0-11.0. It readily hydrolyzed all the tested protein substrates but exhibited highest affinity for gelatin (Km 0.15 mg mL-1). It retained at least 66.20.02% of its original activity in the presence of the tested local commercial detergents and removed bloodstains completely. Its activity was significantly (p>0.05) enhanced by Cu2+ ion but strongly inhibited (75.60.07%) by Phenyl-methyl Sulfonyl Fluoride (PMSF). Thus, the enzyme demonstrated desirable properties suitable for its biotechnological applications especially in detergent industry.
Gamma-glutamyltransferases: exploring the complexity of a multi-functional family of enzymes.
Maria Franzini,Alfonso Pompella,Alessandro Corti
Frontiers in Pharmacology , 2014, DOI: 10.3389/fphar.2014.00215
Abstract: Gamma-glutamyltransferase (γ-GT) has long been known as a key enzyme involved in the glutathione (GSH) metabolism. The wide distribution of γ-GT expression in tissues supports its involvement in distinct processes, such as the recovery of cysteine through GSH catabolism and the metabolism of different GSH conjugates, including major inflammatory mediators leukotriene C4 and S-nitroso-glutathione and GSH-xenobiotics adducts formed by the action of glutathione-S-transferases. Most published studies have focused on γ-GT as a member in the cell antioxidant, defensive systems. Conversely, it has been documented that γ-GT may promote pro-oxidant reactions as well, with potential cell regulatory effects ranging from cell proliferation/apoptosis to drug resistance to genomic instability. From a clinical point of view, γ-GT plasma levels are a sensitive index of hepato-biliary disease and alcohol abuse. Nevertheless, during the last decade a series of large-scale, prospective studies have shown that plasma γ-GT values above the median – albeit within the reference range – are independent predictors of cardiovascular mortality, stroke, metabolic syndrome and diabetes. This appears to confirm the involvement of γ-GT in mechanisms of flogosis and hepatocellular damage, which have a role also in cardiovascular diseases and diabetes, and it is not surprising that a better understanding of γ-GT properties matches with the quest of novel γ-GT inhibitors and drugs selectively targeted on this enzyme. Insights into γ-GT structure clearly are of great interest for the development of new therapies for γ-GT-associated diseases. Despite its clinical and physiopathological importance, a full characterization of human γ-GT is still lacking, as regard both its structure and its association with circulating macromolecular complexes. The structural characterization of human γ-GT1 (hGT1) protein has been hampered by its heavily glycosylated structure and by its association with membranes. Indeed, most of the knowledge regarding γ-GT structure comes from investigations in bacteria. In their book “Gamma-Glutamyl Transpeptidases: Structure and Function” (Castellano and Merlino, 2013) the Authors provide an extensive coverage of the state-of-art knowledge on all aspects of protein structure (e.g. the autoprocessing mechanism, substrate binding sites) and enzyme reaction mechanisms. The book also provides a succinct overview of γ-GT gene family, as well as of its role in human pathology with particular regard to cancer. The latter however is a less interesting section, as the same
Acta bioethica , 2003, DOI: 10.4067/S1726-569X2003000100002
Abstract: due to their intrinsic nature, biotechnological systems produce both benefits as well as risks and situations of uncertainty and ignorance. the evaluations of biotechnological systems, of the artifacts produced by them and of their consequences for society and the environment, depend both on intrinsic values of those systems as well as on values extrinsic to them, which in turn vary from one social group to another and which can hardly coincide completely. such axiological plurality must be taken into account in reviewing biotechnology, for example about biosafety issues by experts from different social sectors (state agents, managers, non governmental organizations, advocacy groups) therefore, mechanisms of participation of experts from different natural, social and humanistic disciplines must be established, along with non experts representing the social sectors with interests. these will watch over the impact of biotechnological systems and their artifacts, they will be able to take decisions and carry out actions to prevent, mitigate or counteract the negative consequences of biotechnology
Michael J. Bangs
Bulletin of Health Research , 2012,
Abstract: Recent biotechnological breakthroughs have led to the development of various methods for detection and identification of human pathogens in their vectors. Monoclonal antibodies produced against malaria sporozoite antigens have permitted the development of several sensitive, species specific immunological tests (IFA, IRMA, ELIS A). One of these, a two-site enzyme-linked immunosorbent assay (ELIS A) has been developed as a useful epidemiological tool in the identification of malaria-infected mosquitoes. This method employs highly species specific monoclonal antibodies that recognize the repetitive immunodominant epitope of the circumsporozoite (CS) protein. Monoclonal antibodies have been developed for all four species of human malaria The key feature of the ELISA technique is the use of an enzyme indicator for an immunological reaction. The antigen capture or "sandwich" ELISA configuration uses the purified monoclonal both as the solid phase and, conjugated to enzyme, as a marker for the presence of CS protein in a mosquito homogenate incubated in the wells of a microtitration plate. This technology has shown advantages over other methods for epidemiological data collection. Mosquitoes can be caught, dried and stored until a time convenient for examination. The sporozoite rate by Plasmodium species can be identified easily, and when combined with the man-biting rate provides the sporozoite inoculation rate, an important entomologic estimate of the number of potential infective bites a person could expect over a given period of time. Presently, mosquitoes can be tested individually or pooled up to 20 anophe lines. The assay is sensitive enough to detect 1 infected mosquito per pool or as few as 25 sporozoites per 50 pi of mosquito extract. Basic principles and procedures are covered concerning solid substrate, adsorption to solid substrate, buffers and wash solutions, conjugates and enzyme substrates. The advantages and limitations of this technique in present malaria studies is discussed.
An Introduction to RFID Technology  [PDF]
Sanjay Ahuja, Pavan Potti
Communications and Network (CN) , 2010, DOI: 10.4236/cn.2010.23026
Abstract: RFID technology emerged some time back and was not used that much because of lack of standardization and high costs. Latest technologies have brought costs down and standards are being developed. Today RFID is mostly used as a medium for numerous tasks including managing supply chains, tracking livestock, preventing counterfeiting, controlling building access, and supporting automated checkout. The use of RFID is limited by security concerns and delays in standardization. This paper describes RFID technology and its applications in today’s world.
Services and Applications Based on Mobile User’s Location Detection and Prediction  [PDF]
M. Abo-Zahhad, Sabah M. Ahmed, M. Mourad
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2013, DOI: 10.4236/ijcns.2013.64020

Many wireless applications are deployed and available to customers via their mobile phones. Variety of these applications and services are based on determination of the current or future location of mobile user. Location based services (LBS) are one of the vital applications which are subdivided into two main categories: economical category and public category. Economic applications include mobile marketing, entertainment and tracking applications. Whereas, emergency cases, safety, traffic management, Muslims’ applications and public information applications are sort of public applications. The first part of the paper presents a new proposed system with developed procedure to recreate public and economic applications with high positioning accuracy and good authentication of users’ data. The developed system is created to enhance both location based services and network allocation resources within mobile network platform using either normal or GPS supported mobile equipment. The second part of the paper introduces future location prediction of mobile user dependent applications. New algorithm is developed depending on utilizing both intra-cell Movement Pattern algorithm (ICMP) [1] and hybrid uplink time Difference of Arrival and Assisted GPS technique (UTDOA_AGPS) [2]. It has been noticed that ICMP algorithm outperforms other future location prediction algorithms with high precision and within suitable time (less than 220) msec. However, UTDOA_AGPS guarantees high precession of mobile user independent of the surrounding environment. The proposed technique is used to enhance reliability and efficiency of location based services using cellular network platform.

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