1
|
Castrejón-Carrillo S, Morales-Moreno LA, Rodríguez-Alegría ME, Zavala-Padilla GT, Bello-Pérez LA, Moreno-Zaragoza J, López Munguía A. Insights into the heterogeneity of levan polymers synthesized by levansucrase Bs-SacB from Bacillus subtilis 168. Carbohydr Polym 2024; 323:121439. [PMID: 37940304 DOI: 10.1016/j.carbpol.2023.121439] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/21/2023] [Accepted: 09/26/2023] [Indexed: 11/10/2023]
Abstract
Levan is an enzymatically synthesized fructose polymer with widely reported structural heterogeneity depending on the producing levansucrase, the reaction conditions employed for its synthesis and the characterization techniques. We studied here the specific properties of levan produced by recombinant levansucrase from B. subtilis 168 (Bs-SacB), often characterized as a bimodal distribution, that is, a mixture of low and high molecular weight levan. We found significant differences between both levans in terms of the already reported molecular weight, size and morphology using different analytical methods. The low molecular weight levan consists of a non-uniform polymer ranging from 50 to 230 kDa, synthesized through a non-processive mechanism that can spontaneously form spherical nanoparticles in the reaction medium. In contrast, high molecular weight levan is a uniform polymer, most probably synthesized through a processive mechanism, with an average molecular weight of 30,750 kDa and a poorly defined nano-structure. This is the first report exploring differences in morphology between low and high molecular weight levans. Our findings demonstrate that only the low molecular weight levan forms spherical nanoparticles in the reaction medium and that high molecular weight levan is mainly composed of a 33,000 kDa fraction with a microgel behavior.
Collapse
Affiliation(s)
- Sol Castrejón-Carrillo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa, 62210 Cuernavaca, Morelos, Mexico.
| | - Luis Alberto Morales-Moreno
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa, 62210 Cuernavaca, Morelos, Mexico
| | - María Elena Rodríguez-Alegría
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa, 62210 Cuernavaca, Morelos, Mexico
| | - Guadalupe Trinidad Zavala-Padilla
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa, 62210 Cuernavaca, Morelos, Mexico.
| | - Luis Arturo Bello-Pérez
- Instituto Politécnico Nacional, CEPROBI, km 6 Carr. Yautepec-Jojutla, Calle Ceprobi No. 8, Apartado Postal 24, Yautepec, Morelos 62731, Mexico.
| | - Josué Moreno-Zaragoza
- Instituto Politécnico Nacional, CEPROBI, km 6 Carr. Yautepec-Jojutla, Calle Ceprobi No. 8, Apartado Postal 24, Yautepec, Morelos 62731, Mexico.
| | - Agustín López Munguía
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001 Chamilpa, 62210 Cuernavaca, Morelos, Mexico.
| |
Collapse
|
2
|
Rodríguez-Suárez JM, Gershenson A, Onuh TU, Butler CS. The Heterogeneous Diffusion of Polystyrene Nanoparticles and the Effect on the Expression of Quorum-Sensing Genes and EPS Production as a Function of Particle Charge and Biofilm Age. ENVIRONMENTAL SCIENCE. NANO 2023; 10:2551-2565. [PMID: 37868332 PMCID: PMC10585598 DOI: 10.1039/d3en00219e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
Biofilms are abundantly present in both natural and engineered environmental systems and will likely influence broader particle fate and transport phenomena. While some developed models describe the interactions between nanoparticles and biofilms, studies are only beginning to uncover the complexity of nanoparticle diffusion patterns. With the knowledge of the nanoparticle potential to influence bacterial processes, more systematic studies are needed to uncover the dynamics of bacteria-nanoparticle interactions. This study explored specific microbial responses to nanoparticles and the heterogeneity of nanoparticle diffusion. Pseudomonas aeruginosa biofilms (cultivated for 48 and 96 hours, representing early and late stages of development) were exposed to charged (aminated and carboxylated) polystyrene nanoparticles. With a combination of advanced fluorescence microscopy and real time quantitative PCR, we characterized the diffusion of polystyrene nanoparticles in P. aeruginosa biofilms and evaluated how biofilms respond to the presence of nanoparticles in terms of the expression of key EPS production-associated genes (pelA and rpsL) and quorum-sensing associated (lasR) genes. Our findings show that nanoparticle diffusion coefficients are independent of the particle surface charge only in mature biofilms and that the presence of nanoparticles influences bacterial gene expression. Independent of the particle's charge polystyrene nanoparticles down-regulated pelA in mature biofilms. By contrast, charge-specific responses were identified in lasR and rpsL gene expression. The targeted genes expression analysis and heterogeneous diffusion models demonstrate that particle charge influences nanoparticle mobility and provides significant insight into the intrinsic structural heterogeneity of P. aeruginosa biofilms. These findings suggest that biofilm maturity and particle charge are essential factors to consider when evaluating the transport of nanoparticles within a biofilm matrix.
Collapse
Affiliation(s)
- Joann M. Rodríguez-Suárez
- Department of Civil and Environmental Engineering, University of Massachusetts Amherst, Amherst MA 01003
| | - Anne Gershenson
- Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst MA 01003
| | - Timothy Umma Onuh
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst MA 01003
| | - Caitlyn S. Butler
- Department of Civil and Environmental Engineering, University of Massachusetts Amherst, Amherst MA 01003
| |
Collapse
|
3
|
Megusar P, Stopar D, Poklar Ulrih N, Dogsa I, Prislan I. Thermal and Rheological Properties of Gluten-Free, Starch-Based Model Systems Modified by Hydrocolloids. Polymers (Basel) 2022; 14:polym14163242. [PMID: 36015498 PMCID: PMC9415605 DOI: 10.3390/polym14163242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/22/2022] [Accepted: 07/26/2022] [Indexed: 12/05/2022] Open
Abstract
Obtaining good-quality gluten-free products represents a technological challenge; thus, it is important to understand how and why the addition of hydrocolloids influences the properties of starch-based products. To obtain insight into the physicochemical changes imparted by hydrocolloids on gluten-free dough, we prepared several suspensions with different corn starch/potato starch/hydroxpropyl methyl cellulose/xanthan gum/water ratios. Properties of the prepared samples were determined by differential scanning calorimetry and rheometry. Samples with different corn/potato starch ratios exhibited different thermal properties. Xanthan gum and HPMC (hydroxypropyl methyl cellulose) exhibited a strong influence on the rheological properties of the mixtures since they increased the viscosity and elasticity. HPMC and xanthan gum increased the temperature of starch gelatinization, as well as they increased the viscoelasticity of the starch model system. Although the two hydrocolloids affected the properties of starch mixtures in the same direction, the magnitude of their effects was different. Our results indicate that water availability, which plays a crucial role in the starch gelatinization process, could be modified by adding hydrocolloids such as, hydroxypropyl methyl cellulose and xanthan gum. By adding comparatively small amounts of the studied hydrocolloids to starch, one can achieve similar thermo-mechanical effects by the addition of gluten. Understanding these effects of hydrocolloids could contribute to the development of better quality gluten-free bread with optimized ingredient content.
Collapse
Affiliation(s)
- Polona Megusar
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - David Stopar
- Department of Microbiology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Natasa Poklar Ulrih
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Iztok Dogsa
- Department of Microbiology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: (I.D.); (I.P.)
| | - Iztok Prislan
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence: (I.D.); (I.P.)
| |
Collapse
|
4
|
Probing the growth and mechanical properties of Bacillus subtilis biofilms through genetic mutation strategies. Synth Syst Biotechnol 2022; 7:965-971. [PMID: 35756965 PMCID: PMC9194759 DOI: 10.1016/j.synbio.2022.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 05/18/2022] [Accepted: 05/20/2022] [Indexed: 12/02/2022] Open
Abstract
Bacterial communities form biofilms on various surfaces by synthesizing a cohesive and protective extracellular matrix, and these biofilms protect microorganisms against harsh environmental conditions. Bacillus subtilis is a widely used experimental species, and its biofilms are used as representative models of beneficial biofilms. Specifically, B. subtilis biofilms are known to be rich in extracellular polymeric substances (EPS) and other biopolymers such as DNA and proteins like the amyloid protein TasA and the hydrophobic protein BslA. These materials, which form an interconnected, cohesive, three-dimensional polymer network, provide the mechanical stability of biofilms and mediate their adherence to surfaces among other functional contributions. Here, we explored how genetically-encoded components specifically contribute to regulate the growth status, mechanical properties, and antibiotic resistance of B. subtilis biofilms, thereby establishing a solid empirical basis for understanding how various genetic engineering efforts are likely to affect the structure and function of biofilms. We noted discrete contributions to biofilm morphology, mechanical properties, and survival from major biofilm components such as EPS, TasA and BslA. For example, EPS plays an important role in maintaining the stability of the mechanical properties and the antibiotic resistance of biofilms, whereas BslA has a significant impact on the resolution that can be obtained for printing applications. This work provides a deeper understanding of the internal interactions of biofilm components through systematic genetic manipulations. It thus not only broadens the application prospects of beneficial biofilms, but also serves as the basis of future strategies for targeting and effectively removing harmful biofilms.
Collapse
|
5
|
Effects of pH on the Properties of Membrane Vesicles Including Glucosyltransferase in Streptococcus mutans. Microorganisms 2021; 9:microorganisms9112308. [PMID: 34835434 PMCID: PMC8618110 DOI: 10.3390/microorganisms9112308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 11/29/2022] Open
Abstract
Streptococcus mutans releases membrane vesicles (MVs) and induces MV-dependent biofilm formation. Glucosyltransferases (Gtfs) are bound to MVs and contribute to the adhesion and glucans-dependent biofilm formation of early adherent bacteria on the tooth surface. The biofilm formation of S. mutans may be controlled depending on whether the initial pH tends to be acidic or alkaline. In this study, the characteristics and effects of MVs extracted from various conditions {(initial pH 6.0 and 8.0 media prepared with lactic acid (LA) and acetic acid (AA), and with NaOH (NO), respectively)} on the biofilm formation of S. mutans and early adherent bacteria were investigated. The quantitative changes in glucans between primary pH 6.0 and 8.0 conditions were observed, associated with different activities affecting MV-dependent biofilm formation. The decreased amount of Gtfs on MVs under the initial pH 6.0 conditions strongly guided low levels of MV-dependent biofilm formation. However, in the initial pH 6.0 and 8.0 solutions prepared with AA and NO, the MVs in the biofilm appeared to be formed by the expression of glucans and/or extracellular DNA. These results suggest that the environmental pH conditions established by acid and alkaline factors determine the differences in the local pathogenic activities of biofilm development in the oral cavity.
Collapse
|
6
|
Control of the aqueous solubility of cellulose by hydroxyl group substitution and its effect on processing. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
7
|
Kırtel O, Aydın H, Toksoy Öner E. Fructanogenic traits in halotolerant Bacillus licheniformis OK12 and their predicted functional significance. J Appl Microbiol 2021; 131:1391-1404. [PMID: 33484024 DOI: 10.1111/jam.15015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 01/26/2023]
Abstract
AIMS Isolating a novel bacterial source of fructan from a saltern and analysis of its genome to better understand the possible roles of fructans in hypersaline environments. METHODS AND RESULTS Bacteria were isolated from crude salt samples originating from Çamaltı Saltern in Western Turkey and screened for fructanogenic traits in high-salt and sucrose-rich selective medium. Exopolysaccharide accumulated in the presence of sucrose by isolate OK12 was purified and chemically characterized via HPLC, FT-IR and NMR, which revealed that it was a levan-type fructan (β-2,6 linked homopolymer of fructose). The isolate was taxonomically classified as Bacillus licheniformis OK12 through 16S rRNA gene and whole-genome sequencing methods. Strain OK12 harbours one levansucrase and two different levanase genes, which altogether were predicted to significantly contribute to intracellular glucose and fructose pools. The isolate could withstand 15% NaCl, and thus classified as a halotolerant. CONCLUSIONS Fructanogenic traits in halotolerant B. licheniformis OK12 are significant due to predicted influx of glucose and fructose as a result of levan biosynthesis and levan hydrolysis, respectively. SIGNIFICANCE AND IMPACT OF THE STUDY Fructans from the residents of hypersaline habitats are underexplored compounds and are expected to demonstrate physicochemical properties different from their non-halophilic counterparts. Revealing fructanogenic traits in the genome of a halotolerant bacterium brings up a new perspective in physiological roles of fructans.
Collapse
Affiliation(s)
- O Kırtel
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Bioengineering Department, Göztepe Campus, Marmara University, Istanbul, Turkey
| | - H Aydın
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Bioengineering Department, Göztepe Campus, Marmara University, Istanbul, Turkey
| | - E Toksoy Öner
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Bioengineering Department, Göztepe Campus, Marmara University, Istanbul, Turkey
| |
Collapse
|
8
|
Ido N, Lybman A, Hayet S, Azulay DN, Ghrayeb M, Liddawieh S, Chai L. Bacillus subtilis biofilms characterized as hydrogels. Insights on water uptake and water binding in biofilms. SOFT MATTER 2020; 16:6180-6190. [PMID: 32567645 DOI: 10.1039/d0sm00581a] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Biofilms are aggregates of cells that form on surfaces or at the air-water interface. Cells in a biofilm are encased in a self-secreted extracellular matrix (ECM) that provides them with mechanical stability and protects them from antibiotic treatment. From a soft matter perspective, biofilms are regarded as colloidal hydrogels, with the cells playing the role of colloids and the ECM compared with a cross-linked hydrogel. Here, we examined whole biofilms of the soil bacterium Bacillus subtilis utilizing methods that are commonly used to characterize hydrogels in order to evaluate the uptake of water and the water properties in the biofilms. Specifically, we studied wild-type as well ECM mutants, lacking the protein TasA and the exopolysaccharide (EPS). We characterized the morphology and mesh size of biofilms using electron microscopy, studied the state of water in the biofilms using differential scanning calorimetry, and finally, we tested the biofilms' swelling properties. Our study revealed that Bacillus subtilis biofilms resemble cross-linked hydrogels in their morphology and swelling properties. Strikingly, we discovered that all the water in biofilms was bound water and there was no free water in the biofilms. Water binding was mostly related with the presence of solutes and much less so with the major ECM components, the protein TasA and the polysaccharide EPS. This study sheds light on water uptake and water binding in biofilms and it is therefore important for the understanding of solute transport and enzymatic function inside biofilms.
Collapse
Affiliation(s)
- Nir Ido
- The Israel Institute for Biological Research, Ness Ziona, Israel
| | - Amir Lybman
- The Israel Institute for Biological Research, Ness Ziona, Israel
| | - Shahar Hayet
- Institute of Chemistry, The Hebrew University of Jerusalem and The Center for Nanoscience and Nanotechnology, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| | - David N Azulay
- Institute of Chemistry, The Hebrew University of Jerusalem and The Center for Nanoscience and Nanotechnology, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| | - Mnar Ghrayeb
- Institute of Chemistry, The Hebrew University of Jerusalem and The Center for Nanoscience and Nanotechnology, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| | - Sajeda Liddawieh
- Institute of Chemistry, The Hebrew University of Jerusalem and The Center for Nanoscience and Nanotechnology, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| | - Liraz Chai
- Institute of Chemistry, The Hebrew University of Jerusalem and The Center for Nanoscience and Nanotechnology, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| |
Collapse
|
9
|
Chaves S, Longo M, Gómez López A, Del V Loto F, Mechetti M, Romero CM. Control of microbial biofilm formation as an approach for biomaterials synthesis. Colloids Surf B Biointerfaces 2020; 194:111201. [PMID: 32615520 DOI: 10.1016/j.colsurfb.2020.111201] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/13/2020] [Accepted: 06/15/2020] [Indexed: 11/26/2022]
Abstract
The search for new biomaterials with superior mechanical properties is the focus in the area of materials science. A promising pathway is drawing inspiration from nature to design and develop materials with enhanced properties. In this work, a novel strategy to produce functionalized supramolecular bionanomaterials from the microbial biofilm is reported. Tuneable biofilms with specific characteristics were obtained by controlling the culture condition of the microorganism. When the exopolysaccharide (EPS) production was desired the tryptone was the best nutritional component for the EPS production into the biofilm. However, for the expression of a high amount of amyloid protein the combination of peptone and glucose was the best nutritional choice. Each biofilm obtained showed its owner rheology properties. These properties were altered by the addition of extracellular DNA, which increased the viscosity of the biofilm and induced a viscoelastic hydrogel behavior. Besides, as a proof of concept of bionanomaterial, a novel supramolecular polymeric hybrid EPS-Amyloid protein (EPAP) was obtained from the biofilm and it was tested as a new natural functionalized support for enzyme immobilization. The results suggest that this technology could be used as a new concept to obtain biomaterials from biofilms by controlling the nutritional conditions of a microorganism. Understanding environmental factors affecting biofilm formation will help the development of methods for controlling biofilm production and therefore obtaining new biomaterials.
Collapse
Affiliation(s)
- Silvina Chaves
- Instituto de Medicina Molecular y Celular Aplicada (IMMCA), CONICET-UNT-SIPROSA, Pje. Dorrego 1080, San Miguel de Tucumán, Argentina
| | - Marianella Longo
- Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina
| | - Azucena Gómez López
- Laboratorio de Física de Fluidos y Electrorreología, Instituto de Física del Noroeste Argentino-INFINOA (CONICET-UNT), Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, 4000, Argentina
| | - Flavia Del V Loto
- Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina
| | - Magdalena Mechetti
- Laboratorio de Física de Fluidos y Electrorreología, Instituto de Física del Noroeste Argentino-INFINOA (CONICET-UNT), Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, 4000, Argentina
| | - Cintia M Romero
- Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina.
| |
Collapse
|
10
|
de Siqueira EC, Rebouças JDS, Pinheiro IO, Formiga FR. Levan-based nanostructured systems: An overview. Int J Pharm 2020; 580:119242. [PMID: 32199961 DOI: 10.1016/j.ijpharm.2020.119242] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 03/05/2020] [Accepted: 03/17/2020] [Indexed: 11/15/2022]
Abstract
Bacterial levan is a fructose homopolymer that offers great potential in biotechnological applications due to biocompatibility, biodegradability and non-toxicity. This biopolymer possesses diverse multifunctional features, which translates into a wide range of applicability, including in industry, consumer products, pharmaceuticals and biomedicine. Extensive research has identified great potential for its exploitation in human health. In addition, nanostructured systems have provided significant advances in the area of health, mainly with respect to disease diagnosis and treatment. While the functional properties of these natural polysaccharide-based polymers are desirable in these systems, research in this area has been limited to few natural polymers, such as chitosan, alginate and dextran, which obscures the true potential of levan in the production of nanostructured systems for biotechnological and medical applications. The present review considers the latest research in the field to focus on the use of levan as a promising biopolymer for the development of nanomaterials.
Collapse
Affiliation(s)
- Edmilson Clarindo de Siqueira
- Programa de Pós-Graduação em Biologia Celular e Molecular Aplicada, Universidade de Pernambuco (UPE), 50100-130 Recife, PE, Brazil
| | - Juliana de Souza Rebouças
- Programa de Pós-Graduação em Ciências da Saúde, Universidade de Pernambuco (UPE), 50100-130 Recife, PE, Brazil
| | - Irapuan Oliveira Pinheiro
- Programa de Pós-Graduação em Biologia Celular e Molecular Aplicada, Universidade de Pernambuco (UPE), 50100-130 Recife, PE, Brazil
| | - Fabio Rocha Formiga
- Programa de Pós-Graduação em Biologia Celular e Molecular Aplicada, Universidade de Pernambuco (UPE), 50100-130 Recife, PE, Brazil; Instituto Aggeu Magalhães, Fundação Oswaldo Cruz (FIOCRUZ), 50670-420 Recife, PE, Brazil.
| |
Collapse
|
11
|
Hundschell CS, Braun A, Wefers D, Vogel RF, Jakob F. Size-Dependent Variability in Flow and Viscoelastic Behavior of Levan Produced by Gluconobacter albidus TMW 2.1191. Foods 2020; 9:E192. [PMID: 32075024 PMCID: PMC7073539 DOI: 10.3390/foods9020192] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/05/2020] [Accepted: 02/11/2020] [Indexed: 12/15/2022] Open
Abstract
Levan is a fructan-type exopolysaccharide which is produced by many microbes from sucrose via extracellular levansucrases. The hydrocolloid properties of levan depend on its molecular weight, while it is unknown why and to what extent levan is functionally diverse depending on its size. The aim of our study was to gain deeper insight into the size-dependent functional variability of levan. For this purpose, levans of different sizes were produced using the water kefir isolate Gluconobacter albidus TMW 2.1191 and subsequently rheologically characterized. Three levan types could be identified, which are similarly branched, but differ significantly in their molecular size and rheological properties. The smallest levan (<107 Da), produced without adjustment of the pH, exhibited Newton-like flow behavior up to a specific concentration of 25% (w/v). By contrast, larger levans (>108 Da) produced at pH ≥ 4.5 were shear-thinning, and the levan produced at pH 5.0 showed a gel-like behavior at 5% (w/v). A third (intermediate) levan variant was obtained through production in buffers at pH 4.0 and exhibited the properties of a viscoelastic fluid up to concentrations of 15% (w/v). Our study reveals that the rheological properties of levan are determined by its size and polydispersity, rather than by the amount of levan used or the structural composition.
Collapse
Affiliation(s)
- Christoph S. Hundschell
- Chair of Technical Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354 Freising, Germany;
- Department of Food Technology and Food Material Science, Technical University of Berlin, 14195 Berlin, Germany;
| | - Andre Braun
- Anton Paar Germany GmbH, Hellmuth-Hirth-Strasse 6, 73760 Ostfildern-Scharnhausen, Germany;
- Lehrstuhl für Systemverfahrenstechnik, Technische Universität München, Gregor-Mendel-Straße 4, 85354 Freising, Germany
| | - Daniel Wefers
- Division of Food Chemistry, Institute of Chemistry, Martin-Luther-University Halle-Wittenberg, 06120 Halle (Saale), Germany;
- Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Rudi F. Vogel
- Chair of Technical Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354 Freising, Germany;
| | - Frank Jakob
- Chair of Technical Microbiology, Technical University of Munich, Gregor-Mendel-Straße 4, 85354 Freising, Germany;
| |
Collapse
|
12
|
Hundschell CS, Wagemans AM. Rheology of common uncharged exopolysaccharides for food applications. Curr Opin Food Sci 2019. [DOI: 10.1016/j.cofs.2019.02.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
13
|
Romero CM, Martorell PV, López AG, Peñalver CGN, Chaves S, Mechetti M. Architecture and physicochemical characterization of Bacillus biofilm as a potential enzyme immobilization factory. Colloids Surf B Biointerfaces 2017; 162:246-255. [PMID: 29216511 DOI: 10.1016/j.colsurfb.2017.11.057] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/09/2017] [Accepted: 11/22/2017] [Indexed: 11/18/2022]
Abstract
Biocatalysis for industrial application is based on the use of enzymes to perform complex transformations. However, these systems have some disadvantage related to the costs of the biocatalyst. In this work, an alternative strategy for producing green immobilized biocatalysts based on biofilm was developed.A study of the rheological behavior of the biofilm from Bacillus sp. Mcn4, as well as the determination of its composition, was carried out. The dynamic rheological measurements, viscosity (G") and elasticity (G') module, showed that the biofilm presents appreciable elastic components, which is a recognized property for enzymes immobilization. After the partial purification, the exopolysaccharidewas identified as a levan with a non-Newtonian behavior. Extracellular DNA with fragments between 10,000 and 1000bp was detected also in the biofilm, and amyloid protein in the extracellular matrix using a fluorescence technique was identified. Bacillus sp. Mcn4 biofilms were developed on different surfaces, being the most stable those developed on hydrophilic supports. The biofilm showed lipase activity suggesting the presence of constitutive lipases entrapped into the biofilm. Indeed, two enzymes with lipase activity were identified in native PAGE. These were used as biocatalysts, whose reuse showed a residual lipase activity after more than one cycle of catalysis. The components identified in the biofilm could be the main contributors of the rheological characteristic of this material, giving an exceptional environment to the lipase enzyme. Based on these findings, the current study proposes green and natural biopolymers matrix as support for the enzyme immobilization for industrial applications.
Collapse
Affiliation(s)
- C M Romero
- PROIMI, PROIMI-CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina.
| | - P V Martorell
- PROIMI, PROIMI-CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina
| | - A Gómez López
- Laboratorio de Física de Fluidos y Electrorreología, Instituto de Física del Noroeste Argentino-INFINOA (CONICET-UNT), Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, 4000, Argentina
| | - C G Nieto Peñalver
- PROIMI, PROIMI-CONICET, Av. Belgrano y Pasaje Caseros, T4001 MVB, Tucumán Fac. Bioq., Qca. y Farmacia (UNT), Ayacucho 471, 4000, Tucumán, Argentina
| | - S Chaves
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina
| | - M Mechetti
- Laboratorio de Física de Fluidos y Electrorreología, Instituto de Física del Noroeste Argentino-INFINOA (CONICET-UNT), Facultad de Ciencias Exactas y Tecnología, Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, 4000, Argentina
| |
Collapse
|
14
|
Sretenovic S, Stojković B, Dogsa I, Kostanjšek R, Poberaj I, Stopar D. An early mechanical coupling of planktonic bacteria in dilute suspensions. Nat Commun 2017; 8:213. [PMID: 28790301 PMCID: PMC5548916 DOI: 10.1038/s41467-017-00295-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 06/19/2017] [Indexed: 11/13/2022] Open
Abstract
It is generally accepted that planktonic bacteria in dilute suspensions are not mechanically coupled and do not show correlated motion. The mechanical coupling of cells is a trait that develops upon transition into a biofilm, a microbial community of self-aggregated bacterial cells. Here we employ optical tweezers to show that bacteria in dilute suspensions are mechanically coupled and show long-range correlated motion. The strength of the coupling increases with the growth of liquid bacterial culture. The matrix responsible for the mechanical coupling is composed of cell debris and extracellular polymer material. The fragile network connecting cells behaves as viscoelastic liquid of entangled extracellular polymers. Our findings point to physical connections between bacteria in dilute bacterial suspensions that may provide a mechanistic framework for understanding of biofilm formation, osmotic flow of nutrients, diffusion of signal molecules in quorum sensing, or different efficacy of antibiotic treatments at low and high bacterial densities.Planktonic bacteria are untethered to surfaces or to each other, and thus are expected to move independently when at low cell densities. Here Sretenovic et al. show, using optical tweezers, that bacteria in dilute suspensions are mechanically coupled and show long-range correlated motion.
Collapse
Affiliation(s)
- Simon Sretenovic
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Biljana Stojković
- Medical Faculty, Institute of Biophysics, University of Ljubljana, Vrazov trg 2, Ljubljana, 1000, Slovenia
| | - Iztok Dogsa
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Rok Kostanjšek
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia
| | - Igor Poberaj
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, Ljubljana, 1000, Slovenia
- Aresis Ltd., Ulica Franca Mlakarja 1a, Ljubljana, 1000, Slovenia
| | - David Stopar
- Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, 1000, Slovenia.
| |
Collapse
|
15
|
Raffinose Induces Biofilm Formation by Streptococcus mutans in Low Concentrations of Sucrose by Increasing Production of Extracellular DNA and Fructan. Appl Environ Microbiol 2017; 83:AEM.00869-17. [PMID: 28526794 DOI: 10.1128/aem.00869-17] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 05/13/2017] [Indexed: 02/06/2023] Open
Abstract
Streptococcus mutans is the primary etiological agent of dental caries and causes tooth decay by forming a firmly attached biofilm on tooth surfaces. Biofilm formation is induced by the presence of sucrose, which is a substrate for the synthesis of extracellular polysaccharides but not in the presence of oligosaccharides. Nonetheless, in this study, we found that raffinose, which is an oligosaccharide with an intestinal regulatory function and antiallergic effect, induced biofilm formation by S. mutans in a mixed culture with sucrose, which was at concentrations less than those required to induce biofilm formation directly. We analyzed the possible mechanism behind the small requirement for sucrose for biofilm formation in the presence of raffinose. Our results suggested that sucrose contributed to an increase in bacterial cell surface hydrophobicity and biofilm formation. Next, we examined how the effects of raffinose interacted with the effects of sucrose for biofilm formation. We showed that the presence of raffinose induced fructan synthesis by fructosyltransferase and aggregated extracellular DNA (eDNA, which is probably genomic DNA released from dead cells) into the biofilm. eDNA seemed to be important for biofilm formation, because the degradation of DNA by DNase I resulted in a significant reduction in biofilm formation. When assessing the role of fructan in biofilm formation, we found that fructan enhanced eDNA-dependent cell aggregation. Therefore, our results show that raffinose and sucrose have cooperative effects and that this induction of biofilm formation depends on supportive elements that mainly consist of eDNA and fructan.IMPORTANCE The sucrose-dependent mechanism of biofilm formation in Streptococcus mutans has been studied extensively. Nonetheless, the effects of carbohydrates other than sucrose are inadequately understood. Our findings concerning raffinose advance the understanding of the mechanism underlying the joint effects of sucrose and other carbohydrates on biofilm formation. Since raffinose has been reported to have positive effects on enterobacterial flora, research on the effects of raffinose on the oral flora are required prior to its use as a beneficial sugar for human health. Here, we showed that raffinose induced biofilm formation by S. mutans in low concentrations of sucrose. The induction of biofilm formation generally generates negative effects on the oral flora. Therefore, we believe that this finding will aid in the development of more effective oral care techniques to maintain oral flora health.
Collapse
|
16
|
González-Garcinuño Á, Tabernero A, Domínguez Á, Galán MA, Martin del Valle EM. Levan and levansucrases: Polymer, enzyme, micro-organisms and biomedical applications. BIOCATAL BIOTRANSFOR 2017. [DOI: 10.1080/10242422.2017.1314467] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Antonio Tabernero
- Department of Chemical Engineering, University of Salamanca, Salamanca, Spain
| | - Ángel Domínguez
- Department of Microbiology and Genetics, University of Salamanca, Salamanca, Spain
| | - Miguel A. Galán
- Department of Chemical Engineering, University of Salamanca, Salamanca, Spain
| | | |
Collapse
|
17
|
Supramolecular structure of methyl cellulose and lambda- and kappa-carrageenan in water: SAXS study using the string-of-beads model. Carbohydr Polym 2017; 172:184-196. [PMID: 28606524 DOI: 10.1016/j.carbpol.2017.04.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 04/11/2017] [Accepted: 04/18/2017] [Indexed: 12/24/2022]
Abstract
A detailed data analysis utilizing the string-of-beads model was performed on experimental small-angle X-ray scattering (SAXS) curves in a targeted structural study of three, very important, industrial polysaccharides. The results demonstrate the quality of performance for this model on three polymers with quite different thermal structural behavior. Furthermore, they show the advantages of the model used by way of excellent fits in the ranges where the classic approach to the small-angle scattering data interpretation fails and an additional 3D visualization of the model's molecular conformations and anticipated polysaccharide supramolecular structure. The importance of this study is twofold: firstly, the methodology used and, secondly, the structural details of important biopolymers that are widely applicable in practice.
Collapse
|
18
|
Alba K, Bingham RJ, Kontogiorgos V. Mesoscopic structure of pectin in solution. Biopolymers 2017; 107. [DOI: 10.1002/bip.23016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/07/2017] [Accepted: 01/25/2017] [Indexed: 01/08/2023]
Affiliation(s)
- K. Alba
- Department of Biological Sciences; University of Huddersfield; HD1 3DH United Kingdom
| | - R. J. Bingham
- Department of Biological Sciences; University of Huddersfield; HD1 3DH United Kingdom
| | - V. Kontogiorgos
- Department of Biological Sciences; University of Huddersfield; HD1 3DH United Kingdom
| |
Collapse
|