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Differentiation of human ES cell-derived neural progenitors to neuronal cells with regional specific identity by co-culturing of notochord and somite. Stem Cell Res 2012; 8:120-33. [DOI: 10.1016/j.scr.2011.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 08/26/2011] [Accepted: 08/28/2011] [Indexed: 01/08/2023] Open
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ANIFANTAKI ELENI, TOULOUPAKIS ELEFTHERIOS, GHANOTAKIS DEMETRIOSF. ALLIINASE IMMOBILIZATION IN CALCIUM ALGINATE BEADS AND LAYERED DOUBLE HYDROXIDES MATRICES. J Food Biochem 2011. [DOI: 10.1111/j.1745-4514.2010.00510.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
O alginato é um copolímero linear constituído de unidades de ácidos α-L-gulurônicos e β-D-manurônicos e é extensamente utilizado devido as suas propriedades espessantes, estabilizantes e gelificantes. Estas características fazem com que este biopolímero encontre aplicações na indústria de alimentos, na indústria têxtil e de papel, em cosméticos e na área farmacêutica e médica. Atualmente para este conjunto de aplicações sua principal fonte são algas marrons, entretanto, o alginato pode ser obtido a partir de biossíntese, utilizando-se microrganismos do gênero Pseudomonas e Azotobacter. A produção bacteriana de alginato apresenta-se como uma alternativa interessante e sua produção por microrganismos, além de possibilitar a produção de biopolímeros de alta qualidade com características específicas e pré-determinadas, irá diminuir o impacto ambiental nas regiões em que as algas marinhas das quais é extraído são coletadas. Nos últimos anos, vários estudos relacionados à produção de alginato por microrganismos foram realizados com o objetivo de avaliar sua produção e rota metabólica de biossíntese, para caracterizar o material produzido e para determinar as potencialidades de aplicação deste novo material. O rápido desenvolvimento de aplicações do alginato na área médica e farmacêutica, bem como a descoberta de propriedades imunológicas únicas deste material tem aumentado o interesse no desenvolvimento de processos para produzi-lo. Neste artigo são abordados aspectos relacionados à produção e as características do alginato bacteriano e também reportadas às potencialidades e aplicações inovadoras nas quais este material vem sendo utilizado.
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Photosensitive controlled release with polyethylene glycol–anthracene modified alginate. Eur J Pharm Biopharm 2011; 79:304-13. [DOI: 10.1016/j.ejpb.2011.03.023] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 03/23/2011] [Accepted: 03/25/2011] [Indexed: 11/20/2022]
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Wells LA, Brook MA, Sheardown H. Generic, Anthracene-Based Hydrogel Crosslinkers for Photo-controllable Drug Delivery. Macromol Biosci 2011; 11:988-98. [DOI: 10.1002/mabi.201100001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 03/10/2011] [Indexed: 11/11/2022]
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Bajpai SK, Chand N, Chaurasia V. Nano Zinc Oxide-Loaded Calcium Alginate Films with Potential Antibacterial Properties. FOOD BIOPROCESS TECH 2011. [DOI: 10.1007/s11947-011-0587-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Ureña-Benavides EE, Kitchens CL. Wide-Angle X-ray Diffraction of Cellulose Nanocrystal−Alginate Nanocomposite Fibers. Macromolecules 2011. [DOI: 10.1021/ma102731m] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Esteban E. Ureña-Benavides
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Christopher L. Kitchens
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, United States
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Ureña-Benavides EE, Brown PJ, Kitchens CL. Effect of jet stretch and particle load on cellulose nanocrystal-alginate nanocomposite fibers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:14263-14270. [PMID: 20712357 DOI: 10.1021/la102216v] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Alginate fibers have found many applications such as the preparation of dressings to treat exuding wounds, drug delivery, enzyme immobilization, etc.; however, their use is limited due to poor mechanical properties. Cellulose nanocrystals (CNCs) were isolated from cotton and introduced into calcium alginate fibers with the goal of improving their strength and modulus. The isolated CNCs are elongated nanoparticles of crystalline cellulose with an average length of 130 nm with a standard deviation (s) of 63 nm, an average width of 20.4 nm (s = 7.8 nm), and an average height of 6.8 nm (s = 3.3 nm). The CNCs were mixed with an aqueous sodium alginate dope solution and wet spun into a CaCl(2) bath to form fibers. It was found that if the apparent jet stretch (ratio of the fiber draw velocity to extrusion velocity) is kept constant, addition of the nanocrystals reduces the tensile strength and modulus of the material; however, a small concentration of CNCs in the dope solution increases the tensile energy to break and enables an increase in the fiber spinning apparent jet stretch ratio by nearly 2-fold at up to 25% CNCs load; the maximum ratio of 4.6 is observed at 25 wt % CNC loading as compared to a maximum of 2.4 for the native alginate. Mechanical testing showed a 38% increase in tenacity and a 123% increase in tensile modulus with 10 wt % CNCs loading and an apparent jet stretch of 4.2. The data suggest that alignment of the nanocrystals in the composites is a key factor influencing the mechanical properties. CNCs have potential to become a biocompatible, renewable, and cost-effective solution to reinforce alginate fibers.
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Affiliation(s)
- Esteban E Ureña-Benavides
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, USA
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Zanphorlin LM, Facchini FDA, Vasconcelos F, Bonugli-Santos RC, Rodrigues A, Sette LD, Gomes E, Bonilla-Rodriguez GO. Production, partial characterization, and immobilization in alginate beads of an alkaline protease from a new thermophilic fungus Myceliophthora sp. J Microbiol 2010; 48:331-6. [PMID: 20571951 DOI: 10.1007/s12275-010-9269-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Accepted: 12/29/2009] [Indexed: 10/19/2022]
Abstract
Thermophilic fungi produce thermostable enzymes which have a number of applications, mainly in biotechnological processes. In this work, we describe the characterization of a protease produced in solidstate (SSF) and submerged (SmF) fermentations by a newly isolated thermophilic fungus identified as a putative new species in the genus Myceliophthora. Enzyme-production rate was evaluated for both fermentation processes, and in SSF, using a medium composed of a mixture of wheat bran and casein, the proteolytic output was 4.5-fold larger than that obtained in SmF. Additionally, the peak of proteolytic activity was obtained after 3 days for SSF whereas for SmF it was after 4 days. The crude enzyme obtained by both SSF and SmF displayed similar optimum temperature at 50 degrees C, but the optimum pH shifted from 7 (SmF) to 9(SSF). The alkaline protease produced through solid-state fermentation (SSF), was immobilized on beads of calcium alginate, allowing comparative analyses of free and immobilized proteases to be carried out. It was observed that both optimum temperature and thermal stability of the immobilized enzyme were higher than for the free enzyme. Moreover, the immobilized enzyme showed considerable stability for up to 7 reuses.
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Vériter S, Mergen J, Goebbels RM, Aouassar N, Grégoire C, Jordan B, Levêque P, Gallez B, Gianello P, Dufrane D. In Vivo Selection of Biocompatible Alginates for Islet Encapsulation and Subcutaneous Transplantation. Tissue Eng Part A 2010; 16:1503-13. [DOI: 10.1089/ten.tea.2009.0286] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sophie Vériter
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Julien Mergen
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Rose-Marie Goebbels
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Najima Aouassar
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Charles Grégoire
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Bénédicte Jordan
- Biomedical Magnetic Resonance Unit, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Philippe Levêque
- Biomedical Magnetic Resonance Unit, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Bernard Gallez
- Biomedical Magnetic Resonance Unit, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Pierre Gianello
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
| | - Denis Dufrane
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculté de Médecine, Brussels, Belgium
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Sagha M, Karbalaie K, Tanhaee S, Esfandiari E, Salehi H, Sadeghi-Aliabadi H, Razavi S, Nasr-Esfahani MH, Baharvand H. Neural Induction in Mouse Embryonic Stem Cells by Co-Culturing With Chicken Somites. Stem Cells Dev 2009; 18:1351-60. [DOI: 10.1089/scd.2008.0341] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Mohsen Sagha
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
- Department of Anatomical Sciences, School of Medicine, Esfahan University of Medical Sciences, Esfahan, Iran
| | - Khadijeh Karbalaie
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
| | - Somaieh Tanhaee
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
| | - Ebrahim Esfandiari
- Department of Anatomical Sciences, School of Medicine, Esfahan University of Medical Sciences, Esfahan, Iran
| | - Hossein Salehi
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
| | - Hojjat Sadeghi-Aliabadi
- Department of Pharmaceutical Chemistry, School of Pharmacy and Esfahan Pharmaceutical Research Center, Esfahan University of Medical Sciences, Esfahan, Iran
| | - Shahnaz Razavi
- Department of Anatomical Sciences, School of Medicine, Esfahan University of Medical Sciences, Esfahan, Iran
| | - Mohammad Hossein Nasr-Esfahani
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
| | - Hossein Baharvand
- Department of Stem Cells, Cell Science Research Center, Royan Institute, Esfahan Campus, Iranian Academic Center for Education, Culture, and Research (ACECR), Esfahan, Iran
- Department of Developmental Biology, University of Science and Culture, Iranian Academic Center for Education, Culture, and Research (ACECR), Tehran, Iran
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Vu B, Chen M, Crawford RJ, Ivanova EP. Bacterial extracellular polysaccharides involved in biofilm formation. Molecules 2009; 14:2535-54. [PMID: 19633622 PMCID: PMC6254922 DOI: 10.3390/molecules14072535] [Citation(s) in RCA: 588] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 06/26/2009] [Accepted: 07/01/2009] [Indexed: 12/19/2022] Open
Abstract
Extracellular polymeric substances (EPS) produced by microorganisms are a complex mixture of biopolymers primarily consisting of polysaccharides, as well as proteins, nucleic acids, lipids and humic substances. EPS make up the intercellular space of microbial aggregates and form the structure and architecture of the biofilm matrix. The key functions of EPS comprise the mediation of the initial attachment of cells to different substrata and protection against environmental stress and dehydration. The aim of this review is to present a summary of the current status of the research into the role of EPS in bacterial attachment followed by biofilm formation. The latter has a profound impact on an array of biomedical, biotechnology and industrial fields including pharmaceutical and surgical applications, food engineering, bioremediation and biohydrometallurgy. The diverse structural variations of EPS produced by bacteria of different taxonomic lineages, together with examples of biotechnological applications, are discussed. Finally, a range of novel techniques that can be used in studies involving biofilm-specific polysaccharides is discussed.
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Affiliation(s)
- Barbara Vu
- Faculty of Life and Social Sciences Swinburne University of Technology, PO Box 218, Hawthorn, Victoria 3122, Australia
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63
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Alginate and pectin composite films crosslinked with Ca2+ ions: Effect of the plasticizer concentration. Carbohydr Polym 2009. [DOI: 10.1016/j.carbpol.2009.02.014] [Citation(s) in RCA: 201] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Anjomshoa M, Karbalaie K, Mardani M, Razavi S, Tanhaei S, Nasr-Esfahani MH, Baharvand H. Generation of motor neurons by coculture of retinoic acid-pretreated embryonic stem cells with chicken notochords. Stem Cells Dev 2009; 18:259-67. [PMID: 18422402 DOI: 10.1089/scd.2008.0049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Understanding neuroectoderm formation and its subsequent diversification to functional neural subtypes remains elusive. We have shown here for the first time that embryonic stem cells (ESCs) can differentiate into neurons and motor neurons (MNs) by using a coculture embryonic notochord model in vitro. Mouse ESCs were induced to form neural precursors via timed exposure to retinoic acid (RA) using the 4-/4+ RA protocol. These cells were then cocultured with alginate bead-encapsulated notochords isolated from Hamburger and Hamilton stage 6-10 chick embryos. The use of notochord alone was not able to induce neural differentiation from ESCs, and, therefore, notochord does not possess neural inducing activity. Hence, the most successful neuronal cells and MN differentiation was only observed following the coculture of RA-pretreated ESCs with notochord. This resulted in a significantly greater number of cells expressing microtubule-associated protein-2 (MAP2), HB9, choline acetyltransferase (ChAT) and MN-specific genes. While further characterization of these differentiated cells will be essential before transplantation studies commence, these data illustrate the effectiveness of embryonic notochord coculture in providing valuable molecular cues for directed differentiation of ESCs toward an MN lineage.
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Affiliation(s)
- Maryam Anjomshoa
- Department of Stem Cells, Cell Science Research Center, Royan Institute, ACECR, Esfahan Campus, Esfahan, Iran
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66
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67
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Gomez d’Ayala G, Malinconico M, Laurienzo P. Marine derived polysaccharides for biomedical applications: chemical modification approaches. Molecules 2008; 13:2069-106. [PMID: 18830142 PMCID: PMC6245343 DOI: 10.3390/molecules13092069] [Citation(s) in RCA: 235] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Revised: 07/02/2008] [Accepted: 07/25/2008] [Indexed: 12/26/2022] Open
Abstract
Polysaccharide-based biomaterials are an emerging class in several biomedical fields such as tissue regeneration, particularly for cartilage, drug delivery devices and gelentrapment systems for the immobilization of cells. Important properties of the polysaccharides include controllable biological activity, biodegradability, and their ability to form hydrogels. Most of the polysaccharides used derive from natural sources; particularly, alginate and chitin, two polysaccharides which have an extensive history of use in medicine, pharmacy and basic sciences, and can be easily extracted from marine plants (algae kelp) and crab shells, respectively. The recent rediscovery of poly-saccharidebased materials is also attributable to new synthetic routes for their chemical modification, with the aim of promoting new biological activities and/or to modify the final properties of the biomaterials for specific purposes. These synthetic strategies also involve the combination of polysaccharides with other polymers. A review of the more recent research in the field of chemical modification of alginate, chitin and its derivative chitosan is presented. Moreover, we report as case studies the results of our recent work concerning various different approaches and applications of polysaccharide-based biomaterials, such as the realization of novel composites based on calcium sulphate blended with alginate and with a chemically modified chitosan, the synthesis of novel alginate-poly(ethylene glycol) copolymers and the development of a family of materials based on alginate and acrylic polymers of potential interest as drug delivery systems.
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Affiliation(s)
| | | | - Paola Laurienzo
- Istituto di Chimica e Tecnologia dei Polimeri, C.N.R.-Via Campi Flegrei, 34- 80078 Pozzuoli (Naples), Italy
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69
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71
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Günday ST, Bozkurt A. Preparation and Proton Conductivity of Polymer Electrolytes Based on Alginic Acid and 1,2,4-Triazole. Polym J 2007. [DOI: 10.1295/polymj.pj2007152] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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73
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Sikorski P, Mo F, Skjåk-Braek G, Stokke BT. Evidence for egg-box-compatible interactions in calcium-alginate gels from fiber X-ray diffraction. Biomacromolecules 2007; 8:2098-103. [PMID: 17530892 DOI: 10.1021/bm0701503] [Citation(s) in RCA: 336] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structures of guluronic-acid-rich alginate in the acid and calcium forms were investigated using fiber X-ray diffraction. Data recorded for alginate fibers in the acid form show a repeat along the chain axis of c = 0.87 nm, a value that is in agreement with the one measured by Atkins et al. (Biopolymers 1973, 12, 1865) and contradicts a repeat of 0.78 nm recently suggested by Li et al. (Biomacromolecules 2007, 8, 464). In the Ca2+ form, our observations indicate that the junction zone involves dimerization of polymer chains through Ca2+ coordination according to the egg-box model. For reasons that are not understood at present, coordination of the divalent cations reduces the ability for the lateral crystallographic packing of the dimers. A proposed model for the junction zone involves polymer chains packed on a hexagonal lattice with a lattice constant a = 0.66 nm. Random pairs of chains form dimers through coordination of Ca2+ cations. Further lateral interaction between dimers is mediated by disordered Na+ and Ca2+ cations, water molecules, and hydrogen bonding.
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Affiliation(s)
- Pawel Sikorski
- Department of Physics and Norwegian Biopolymer Laboratory, Department of Biotechnology, Norwegian University of Science and Technology, Trondheim, Norway.
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74
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Wells LA, Sheardown H. Extended release of high pI proteins from alginate microspheres via a novel encapsulation technique. Eur J Pharm Biopharm 2007; 65:329-35. [PMID: 17156984 DOI: 10.1016/j.ejpb.2006.10.018] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 10/13/2006] [Accepted: 10/18/2006] [Indexed: 11/30/2022]
Abstract
Alginate has potential as a matrix for controlled delivery of protein-based drugs that require site-specific long-term delivery. In the current work albumin, lysozyme and chymotrypsin were encapsulated into alginate microspheres using a novel method that involved soaking the microspheres in a protein-containing NaCl solution. This was followed by recrosslinking with calcium chloride. High pI proteins also appeared to physically crosslink the sodium alginate which resulted in more sustained release. Release was affected by the nature of the releasate solution. In TRIS buffered saline, the high pI proteins chymotrypsin and lysozyme showed sustained release lasting over 150 h. Release into 0.15% NaCl led to relatively constant release of lysozyme and chymotrypsin over more than 2000 h; reduction of the releasate volume lengthened the lysozyme release to greater than 8 months. Released lysozyme was shown to remain active for at least 16 days, in some cases with activity greater than 100% of the active control. This encapsulation technique can therefore be used to rapidly load alginate microspheres with proteins, with high isoelectric point proteins showing particular promise. Furthermore, the interactions between the high pI proteins and the alginate gel could potentially be exploited to generate new protein delivery systems.
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Affiliation(s)
- L A Wells
- Department of Chemical Engineering, McMaster University, Hamilton, Ont., Canada
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75
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Lawrence JR, Swerhone GDW, Kuhlicke U, Neu TR. In situ evidence for microdomains in the polymer matrix of bacterial microcolonies. Can J Microbiol 2007; 53:450-8. [PMID: 17538657 DOI: 10.1139/w06-146] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Confocal laser scanning microscopy and fluorescent lectin-binding analyses (FLBA) were used to study the form, arrangement, and composition of exopolymeric substances (EPS) surrounding naturally occurring microcolonies in biofilms. FLBA, using multiple lectin staining and multichannel imaging, indicated that the EPS of many microcolonies exhibit distinct multiple binding regions. A common pattern in the microcolonies is a three zone arrangement with cell-associated, intercellular, and an outer layer of EPS covering the exterior of the colony. Differential binding of lectins suggests that there are differences in the glycoconjugate composition or their arrangement in the EPS of microcolonies. The combination of FLBA with fluorescent in situ hybridization (FISH) indicates that the colonies consist of the major groups, α- and β-Proteobacteria. It is suggested that the EPS arrangement observed provides a physical structuring mechanism that can segregate extracellular activities at the microscale.
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Affiliation(s)
- J R Lawrence
- National Water Research Institute, 11 Innovation Boulevard, Saskatoon, SK S7N3H5, Canada.
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Brownlee IA, Allen A, Pearson JP, Dettmar PW, Havler ME, Atherton MR, Onsøyen E. Alginate as a source of dietary fiber. Crit Rev Food Sci Nutr 2006; 45:497-510. [PMID: 16183570 DOI: 10.1080/10408390500285673] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Alginate, an algal polysaccharide, is widely used in the food industry as a stabilizer, or as a thickening or emulsifying agent. As an indigestible polysaccharide, alginate may also be viewed as a source of dietary fiber. Previous work has suggested that dietary fibres may protect against the onset and continuation of a number of cardiovascular and gastrointestinal diseases. This article aims to examine what is currently understood about the fiber-like activities of alginate, particularly its effects on intestinal absorption and the colon, and therefore aims to gauge the potential use of alginate as a dietary supplement for the maintenance of normal health, or the alleviation of certain cardiovascular or gastrointestinal diseases.
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Affiliation(s)
- I A Brownlee
- Cell & Molecular Biosciences, University of Newcastle-upon-Tyne, NE2 4HH, UK.
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Bakkevig K, Sletta H, Gimmestad M, Aune R, Ertesvåg H, Degnes K, Christensen BE, Ellingsen TE, Valla S. Role of the Pseudomonas fluorescens alginate lyase (AlgL) in clearing the periplasm of alginates not exported to the extracellular environment. J Bacteriol 2006; 187:8375-84. [PMID: 16321942 PMCID: PMC1317005 DOI: 10.1128/jb.187.24.8375-8384.2005] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alginate is an industrially widely used polysaccharide produced by brown seaweeds and as an exopolysaccharide by bacteria belonging to the genera Pseudomonas and Azotobacter. The polymer is composed of the two sugar monomers mannuronic acid and guluronic acid (G), and in all these bacteria the genes encoding 12 of the proteins essential for synthesis of the polymer are clustered in the genome. Interestingly, 1 of the 12 proteins is an alginate lyase (AlgL), which is able to degrade the polymer down to short oligouronides. The reason why this lyase is associated with the biosynthetic complex is not clear, but in this paper we show that the complete lack of AlgL activity in Pseudomonas fluorescens in the presence of high levels of alginate synthesis is toxic to the cells. This toxicity increased with the level of alginate synthesis. Furthermore, alginate synthesis became reduced in the absence of AlgL, and the polymers contained much less G residues than in the wild-type polymer. To explain these results and other data previously reported in the literature, we propose that the main biological function of AlgL is to degrade alginates that fail to become exported out of the cell and thereby become stranded in the periplasmic space. At high levels of alginate synthesis in the absence of AlgL, such stranded polymers may accumulate in the periplasm to such an extent that the integrity of the cell is lost, leading to the observed toxic effects.
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Affiliation(s)
- Karianne Bakkevig
- Department of Biotechnology, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
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Moreira SM, Moreira-Santos M, Guilhermino L, Ribeiro R. Immobilization of the marine microalga Phaeodactylum tricornutum in alginate for in situ experiments: Bead stability and suitability. Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2005.05.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Öztürk E, Ağalar C, Keçeci K, Denkba?? EB. Preparation and characterization of ciprofloxacin-loaded alginate/chitosan sponge as a wound dressing material. J Appl Polym Sci 2006. [DOI: 10.1002/app.23563] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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81
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Pluemsab W, Sakairi N, Furuike T. Synthesis and inclusion property of α-cyclodextrin-linked alginate. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.08.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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82
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Giulio BD, Orlando P, Barba G, Coppola R, Rosa MD, Sada A, Prisco PPD, Nazzaro F. Use of alginate and cryo-protective sugars to improve the viability of lactic acid bacteria after freezing and freeze-drying. World J Microbiol Biotechnol 2005. [DOI: 10.1007/s11274-004-4735-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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83
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84
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85
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Cosnier S, Mousty C, de?Melo J, Lepellec A, Novoa A, Polyak B, Marks R. Organic Phase PPO Biosensors Prepared by Multilayer Deposition of Enzyme and Alginate Through Avidin-Biotin Interactions. ELECTROANAL 2004. [DOI: 10.1002/elan.200303084] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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86
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87
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Yamada M, Honma I. Alginic acid–imidazole composite material as anhydrous proton conducting membrane. POLYMER 2004. [DOI: 10.1016/j.polymer.2004.10.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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88
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Leonard M, De Boisseson MR, Hubert P, Dalençon F, Dellacherie E. Hydrophobically modified alginate hydrogels as protein carriers with specific controlled release properties. J Control Release 2004; 98:395-405. [PMID: 15312995 DOI: 10.1016/j.jconrel.2004.05.009] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2003] [Accepted: 05/17/2004] [Indexed: 11/19/2022]
Abstract
Amphiphilic derivatives of sodium alginate, prepared by chemical covalent binding of long alkyl chains onto the polysaccharide backbone via ester functions, form strong hydrogels in aqueous solutions. The shear-thinning and thixotropic behaviors of these hydrogels have been exploited to prepare particles (millimetric beads or microparticles) by dispersion in sodium chloride solutions. This all-aqueous procedure was used for the encapsulation of model proteins, such as bovine serum albumin (BSA) and human hemoglobin (Hb), or of a vaccine protein (Helicobacter pylori (H. pylori) urease). In all cases, the encapsulation yields were very high (70-100%). No release of model proteins was observed in water within several days, in contrast with protein-loaded calcium alginate particles, which exhibit an important release within only a few hours. The controlled release of proteins can, however, be achieved by inducing the dissociation of the physical hydrophobic network. This dissociation has been obtained either by addition of surfactants, acting as disrupting agents of intermolecular hydrophobic junctions, or of esterases such as lipases, which hydrolyze the ester bond between alkyl chains and the polysaccharide backbone. The level of immunization against H. pylori infection in mice, induced by encapsulated urease administrated by either systemic or mucosal routes, was also assessed.
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Affiliation(s)
- M Leonard
- Laboratoire de Chimie Physique Macromoléculaire, Groupe ENSIC, BP 451, UMR CNRS-INPL 7568, 54001 Nancy Cedex, France.
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89
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Rastello De Boisseson M, Leonard M, Hubert P, Marchal P, Stequert A, Castel C, Favre E, Dellacherie E. Physical alginate hydrogels based on hydrophobic or dual hydrophobic/ionic interactions: Bead formation, structure, and stability. J Colloid Interface Sci 2004; 273:131-9. [PMID: 15051442 DOI: 10.1016/j.jcis.2003.12.064] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2003] [Accepted: 12/10/2003] [Indexed: 10/26/2022]
Abstract
Hydrophobically associating alginate (AA) derivatives were prepared by covalent fixation of dodecyl or octadecyl chains onto the polysaccharide backbone (AA-C12/AA-C18). In semidilute solution, intermolecular hydrophobic interactions result in the formation of physical hydrogels, the physicochemical properties of which can be controlled through polymer concentration, hydrophobic chain content, and nonchaotropic salts such as sodium chloride. The mechanical properties of these hydrogels can then be reinforced by the addition of calcium chloride. The combination of both calcium bridges and intermolecular hydrophobic interactions leads to a decrease in the swelling ratio accompanied by an increase of elastic and viscous moduli. Beads made of hydrophobically modified alginate were obtained by dropping an aqueous solution of alginate derivative into a NaCl/CaCl2 solution. As compared to unmodified alginate beads, modified alginate particles proved to be stable in the presence of nongelling cations or calcium-sequestering agents. However, evidence is presented for a more heterogeneous structure than that of plain calcium alginate hydrogels with, in particular, an increase in the effective gel mesh size, as determined by partition and diffusion coefficient measurements.
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Affiliation(s)
- M Rastello De Boisseson
- Laboratoire de Chimie Physique Macromoléculaire, UMR CNRS-INPL 7568, Groupe ENSIC, BP 451, 54001 Nancy Cedex, France
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90
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Lee DW, Choi WS, Byun MW, Park HJ, Yu YM, Lee CM. Effect of gamma-irradiation on degradation of alginate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:4819-23. [PMID: 14705918 DOI: 10.1021/jf021053y] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The aqueous solution of alginate was irradiated by 60Co gamma-rays in the dose range of 10-500 kGy. To assess the effect of irradiation on the degradation of alginate, the irradiation-induced changes in the viscosity, molecular weight, color, monomer composition, and sequence were measured. The molecular weight of raw alginate was reduced from 300000 to 25000 when irradiated at 100 kGy. The degradation rate decreased and the chain breaks per molecule increased with increasing irradiation dose. The viscosity of irradiated alginate solution reached a near minimum as low as at 10 kGy. No appreciable color changes were observed in the samples irradiated at up to 100 kGy, but intense browning occurred beyond 200 kGy. The 13C NMR spectra showed that homopolymeric blocks, MM and GG, increased and the M/G ratio decreased with irradiation. Considering both the level of degradation and the color change of alginate, the optimum irradiation dose was found to be 100 kGy.
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Affiliation(s)
- Dong Wook Lee
- Graduate School of Biotechnology, Korea University, Seoul 136-701, Korea
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91
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Shilpa A, Agrawal SS, Ray AR. Controlled Delivery of Drugs from Alginate Matrix. ACTA ACUST UNITED AC 2003. [DOI: 10.1081/mc-120020160] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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92
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Leonard M, Rastello De Boisseson M, Hubert P, Dellacherie E. Production of microspheres based on hydrophobically associating alginate derivatives by dispersion/gelation in aqueous sodium chloride solutions. ACTA ACUST UNITED AC 2003; 68:335-42. [PMID: 14704975 DOI: 10.1002/jbm.a.20006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A new "all aqueous" procedure for the preparation of stable polysaccharide microparticles was developed. The method consists of dispersing a water solution of an amphiphilic alginate derivative (in the current work, alginate substituted with low amounts of dodecyl chains) first fluidified under mechanical stress, into an NaCl solution. The procedure exploits the ability of amphiphilic associative derivatives to form strong hydrogels in the presence of nonchaotropic salts and their shear-thinning/thixotropic properties. Depending on the experimental conditions, the size of the microparticles can be varied from 10 microm to several hundred micrometers. Their mechanical properties can eventually be reinforced by addition of low concentrations of calcium chloride. The resulting microparticles exhibit a better stability than that of plain Ca(2+)-alginate particles, as they are not disrupted when nongelling cations or calcium-sequestering agents are added to the solution. In addition, the particles can be easily redispersed after being centrifuged or freeze-dried.
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Affiliation(s)
- M Leonard
- Laboratoire de Chimie Physique Macromoléculaire, UMR CNRS-INPL 7568, Groupe ENSIC, BP 451, 54001 Nancy Cedex, France
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93
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Saude N, Chèze-Lange H, Beunard D, Dhulster P, Guillochon D, Cazé AM, Morcellet M, Junter GA. Alginate production by Azotobacter vinelandii in a membrane bioreactor. Process Biochem 2002. [DOI: 10.1016/s0032-9592(02)00090-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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94
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Peddie S, Zou J, Secombes CJ. Immunostimulation in the rainbow trout (Oncorhynchus mykiss) following intraperitoneal administration of Ergosan. Vet Immunol Immunopathol 2002; 86:101-13. [PMID: 11943333 DOI: 10.1016/s0165-2427(02)00019-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The present work provides information concerning the immunostimulatory activity of Ergosan, an algal based product, injected intraperitoneally in the rainbow trout (Oncorhynchus mykiss). Ergosan is composed of 0.002% unspecified plant extract, 1% alginic acid from Laminaria digitata, and 98.998% algal based carrier. Migration of leucocytes into the peritoneal cavity was stimulated at doses > or =1 mg ml(-1). A single dose of 1mg significantly augmented the proportion of neutrophils, degree of phagocytosis, respiratory burst activity and expression of interleukin-1beta (IL-1beta), interleukin-8 (IL-8) and one of the two known isoforms of trout tumour necrosis factor-alpha (TNF2) in peritoneal leucocytes at 1 day post-injection. Humoral immune parameters were less responsive to intraperitoneal Ergosan administration, with complement stimulation only evident in the 1mg treated group at 2 days post-injection. Antiprotease and lysozyme activity were unaffected by Ergosan over a 7-day time period at the doses examined.
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Affiliation(s)
- Scott Peddie
- Department of Zoology, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ, Scotland, UK
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95
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96
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Cosnier S, Novoa A, Mousty C, Marks RS. Biotinylated alginate immobilization matrix in the construction of an amperometric biosensor: application for the determination of glucose. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(01)01485-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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97
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Fabrication of organic phase biosensors based on multilayered polyphenol oxidase protected by an alginate coating. Electrochem commun 2001. [DOI: 10.1016/s1388-2481(01)00252-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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98
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Valla S, Li J, Ertesvåg H, Barbeyron T, Lindahl U. Hexuronyl C5-epimerases in alginate and glycosaminoglycan biosynthesis. Biochimie 2001; 83:819-30. [PMID: 11530215 DOI: 10.1016/s0300-9084(01)01313-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The sugar residues in most polysaccharides are incorporated as their corresponding monomers during polymerization. Here we summarize the three known exceptions to this rule, involving the biosynthesis of alginate, and the glycosaminoglycans, heparin/heparan sulfate and dermatan sulfate. Alginate is synthesized by brown seaweeds and certain bacteria, while glycosaminoglycans are produced by most animal species. In all cases one of the incorporated sugar monomers are being C5-epimerized at the polymer level, from D-mannuronic acid to L-guluronic acid in alginate, and from D-glucuronic acid to L-iduronic acid in glycosaminoglycans. Alginate epimerization modulates the mechanical properties of seaweed tissues, whereas in bacteria it seems to serve a wide range of purposes. The conformational flexibility of iduronic acid units in glycosaminoglycans promotes apposition to, and thus functional interactions with a variety of proteins at cell surfaces and in the extracellular matrix. In the bacterium Azotobacter vinelandii the alginates are being epimerized at the cell surface or in the extracellular environment by a family of evolutionary strongly related modular type and Ca(2+)-dependent epimerases (AlgE1-7). Each of these enzymes introduces a specific distribution pattern of guluronic acid residues along the polymer chains, explaining the wide structural variability observed in alginates isolated from nature. Glycosaminoglycans are synthesized in the Golgi system, through a series of reactions that include the C5-epimerization reaction along with extensive sulfation of the polymers. The single, Ca(2+)-independent, epimerase in heparin/heparan sulfate biosynthesis and the Ca(2+)-dependent dermatan sulfate epimerase(s) also generate variable epimerization patterns, depending on other polymer-modification reactions. The alginate and heparin epimerases appear unrelated at the amino acid sequence level, and have probably evolved through independent evolutionary pathways; however, hydrophobic cluster analysis indicates limited similarity. Seaweed alginates are widely used in industry, while heparin is well established in the clinic as an anticoagulant.
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Affiliation(s)
- S Valla
- Department of Biotechnology, The Norwegian University of Science and Technology, 7491 Trondheim, Norway
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99
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Sutherland I. Biofilm exopolysaccharides: a strong and sticky framework. MICROBIOLOGY (READING, ENGLAND) 2001; 147:3-9. [PMID: 11160795 DOI: 10.1099/00221287-147-1-3] [Citation(s) in RCA: 922] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- I Sutherland
- Institute of Cell and Molecular Biology, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JH, UK.
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100
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Kim YJ, Yoon KJ, Ko SW. Preparation and properties of alginate superabsorbent filament fibers crosslinked with glutaraldehyde. J Appl Polym Sci 2000. [DOI: 10.1002/1097-4628(20001205)78:10<1797::aid-app110>3.0.co;2-m] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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