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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.
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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.
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2
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Cui M, Ma Q, Zhang Z, Li W, Chen W, Liu P, Wu D, Yang Y. Semi-solid enzymolysis enhanced the protective effects of fruiting body powders and polysaccharides of Herinaceus erinaceus on gastric mucosal injury. Int J Biol Macromol 2023; 251:126388. [PMID: 37595717 DOI: 10.1016/j.ijbiomac.2023.126388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 06/03/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
This study demonstrated the effects of semi-solid enzymolysis on physicochemical properties of fruiting body powders and polysaccharides from Hericium erinaceus and protective effects on gastric mucosal injury. Semi-solid enzymolysis could reduce the particle size, change the microstructure of fruiting body powders, increase the contents of soluble polysaccharide (26.26-67.04 %) and uronic acid (16.97-31.12 %) and reduce the molecular weight of polysaccharides. The digestibility of fruiting body powder of H. erinaceus after semi-solid enzymolysis was increased by 31.4 %, compared with that of the fruiting body powder of H. erinaceus without enzymolysis. Semi-solid enzymolysis could enhance the protective effects of the fruiting body powders and polysaccharides on ethanol-induced human gastric mucosal epithelial cells (GES-1) cells, increase the production of superoxide dismutase (SOD, 0-37.33 %) and catalase (CAT, 2.47-18.46 %), and inhibit the production of malonaldehyde (MDA, 2.45-19.62 %), myeloperoxidase (MPO, 0-13.54 %), interleukin (IL-6, 4.39-24.62 %) and tumor necrosis factor-α (TNF-α, 5.97-12.25 %). Semi-solid enzymolysis could improve the inhibition rate of the fruiting body powder on gastric ulcer (32.70-46.26 %), inhibit oxidative stress and inflammation, and protect rats with acute gastric mucosal injury against the stimulation of ethanol on gastric mucosa. In conclusion, semi-solid enzymolysis may enhance the protective effects of the fruiting body powders and polysaccharides on gastric mucosal injury.
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Affiliation(s)
- Mingxiao Cui
- Department of Food Science, Shanghai Business School, Shanghai 200235, China
| | - Qiang Ma
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China
| | - Zhong Zhang
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China
| | - Wen Li
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China
| | - Wanchao Chen
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China
| | - Peng Liu
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China
| | - Di Wu
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China.
| | - Yan Yang
- Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, National Engineering Research Center of Edible Fungi, Key Laboratory of Edible Fungi Resources and Utilization (South), Ministry of Agriculture, Shanghai 201403, China.
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3
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Chronopoulou EG. Levansucrase: Enzymatic Synthesis of Engineered Prebiotics. Curr Pharm Biotechnol 2023; 24:199-202. [PMID: 36883258 DOI: 10.2174/1389201023666220421134103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 02/11/2022] [Accepted: 03/03/2022] [Indexed: 11/22/2022]
Affiliation(s)
- Evangelia G Chronopoulou
- Laboratory of Enzyme Technology, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece
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4
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Nasir A, Ahmad W, Sattar F, Ashfaq I, Lindemann SR, Chen MH, Van den Ende W, Ӧner ET, Kirtel O, Khaliq S, Ghauri MA, Anwar MA. Production of a high molecular weight levan by Bacillus paralicheniformis, an industrially and agriculturally important isolate from the buffalo grass rhizosphere. Antonie Van Leeuwenhoek 2022; 115:1101-1112. [PMID: 35840814 DOI: 10.1007/s10482-022-01760-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 06/27/2022] [Indexed: 11/26/2022]
Abstract
A new exopolysaccharide (EPS) producing Gram-positive bacterium was isolated from the rhizosphere of Bouteloua dactyloides (buffalo grass) and its EPS product was structurally characterized. The isolate, designated as LB1-1A, was identified as Bacillus paralicheniformis based on 16S rRNA gene sequence and phylogenetic tree analysis. The EPS produced by LB1-1A was identified as a levan, having β(2 → 6) linked backbone with β(2 → 1) linkages at the branch points (4.66%). The isolate LB1-1A yielded large amount (~ 42 g/l) of levan having high weight average molecular weight (Mw) of 5.517 × 107 Da. The relatively low degree of branching and high molecular weight of this levan makes B. paralicheniformis LB1-1A a promising candidate for industrial applications.
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Affiliation(s)
- Anam Nasir
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
| | - Waqar Ahmad
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
- Department of Microbiology, Abbottabad University of Science and Technology, Havelian, Abbottabad, Pakistan
| | - Fazal Sattar
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
| | - Iram Ashfaq
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
| | - Stephen R Lindemann
- Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN, 47907, USA
| | - Ming-Hsu Chen
- Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN, 47907, USA
- Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Wim Van den Ende
- Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium
| | - Ebru Toksoy Ӧner
- IBSB-Industrial Biotechnology and Systems Biology Research Group, Department of Bioengineering, Marmara University, Göztepe Campus, Istanbul, Turkey
| | - Onur Kirtel
- IBSB-Industrial Biotechnology and Systems Biology Research Group, Department of Bioengineering, Marmara University, Göztepe Campus, Istanbul, Turkey
| | - Shazia Khaliq
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
| | - Muhammad A Ghauri
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan
| | - Munir A Anwar
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College, Pakistan Institute of Engineering and Applied Sciences (NIBGE-C, PIEAS), Punjab, 38000, Faisalabad, Pakistan.
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5
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Kaur H, Kaur A, Soni SK, Rishi P. Microbially-derived cocktail of carbohydrases as an anti-biofouling agents: a 'green approach'. BIOFOULING 2022; 38:455-481. [PMID: 35673761 DOI: 10.1080/08927014.2022.2085566] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 05/12/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Enzymes, also known as biocatalysts, display vital properties like high substrate specificity, an eco-friendly nature, low energy inputs, and cost-effectiveness. Among their numerous known applications, enzymes that can target biofilms or their components are increasingly being investigated for their anti-biofouling action, particularly in healthcare, food manufacturing units and environmental applications. Enzymes can target biofilms at different levels like during the attachment of microorganisms, formation of exopolymeric substances (EPS), and their disruption thereafter. In this regard, a consortium of carbohydrases that can target heterogeneous polysaccharides present in the EPS matrix may provide an effective alternative to conventional chemical anti-biofouling methods. Further, for complete annihilation of biofilms, enzymes can be used alone or in conjunction with other antimicrobial agents. Enzymes hold the promise to replace the conventional methods with greener, more economical, and more efficient alternatives. The present article explores the potential and future perspectives of using carbohydrases as effective anti-biofilm agents.
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Affiliation(s)
- Harmanpreet Kaur
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Arashdeep Kaur
- Department of Microbiology, Panjab University, Chandigarh, India
| | | | - Praveen Rishi
- Department of Microbiology, Panjab University, Chandigarh, India
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6
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Variability of Bacterial Homopolysaccharide Production and Properties during Food Processing. BIOLOGY 2022; 11:biology11020171. [PMID: 35205038 PMCID: PMC8869377 DOI: 10.3390/biology11020171] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/22/2021] [Accepted: 01/18/2022] [Indexed: 02/05/2023]
Abstract
Various homopolysaccharides (HoPSs) can be produced by bacteria: α- and β-glucans, β-fructans and α-galactans, which are polymers of glucose, fructose and galactose, respectively. The synthesis of these compounds is catalyzed by glycosyltransferases (glycansucrases), which are able to transfer the monosaccharides in a specific substrate to the medium, which results in the growth of polysaccharide chains. The range of HoPS sizes is very large, from 104 to 109 Da, and mostly depends on the carbon source in the medium and the catalyzing enzyme. However, factors such as nitrogen nutrients, pH, water activity, temperature and duration of bacterial culture also impact the size and yield of production. The sequence of the enzyme influences the structure of the HoPS, by modulating the type of linkage between monomers, both for the linear chain and for the ramifications. HoPSs' size and structure have an effect on rheological properties of some foods by their influence on viscosity index. As a consequence, the control of structural and environmental factors opens ways to guide the production of specific HoPS in foods by bacteria, either by in situ or ex situ production, but requires a better knowledge of HoPS production conditions.
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Bange G, Bedrunka P. Physiology of guanosine-based second messenger signaling in Bacillus subtilis. Biol Chem 2021; 401:1307-1322. [PMID: 32881708 DOI: 10.1515/hsz-2020-0241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/22/2020] [Indexed: 12/19/2022]
Abstract
The guanosine-based second messengers (p)ppGpp and c-di-GMP are key players of the physiological regulation of the Gram-positive model organism Bacillus subtilis. Their regulatory spectrum ranges from key metabolic processes over motility to biofilm formation. Here we review our mechanistic knowledge on their synthesis and degradation in response to environmental and stress signals as well as what is known on their cellular effectors and targets. Moreover, we discuss open questions and our gaps in knowledge on these two important second messengers.
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Affiliation(s)
- Gert Bange
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Strasse 6, C07, Marburg, D-35043,Germany
| | - Patricia Bedrunka
- Center for Synthetic Microbiology (SYNMIKRO) and Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Strasse 6, C07, Marburg, D-35043,Germany
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8
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Development and Characterization of Two Types of Surface Displayed Levansucrases for Levan Biosynthesis. Catalysts 2021. [DOI: 10.3390/catal11070757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Levan has wide applications in chemical, cosmetic, pharmaceutical and food industries. The free levansucrase is usually used in the biosynthesis of levan, but the poor reusability and low stability of free levansucrase have limited its large-scale use. To address this problem, the surface-displayed levansucrase in Saccharomyces cerevisiae were generated and evaluated in this study. The levansucrase from Zymomonas mobilis was displayed on the cell surface of Saccharomyces cerevisiae EBY100 using a various yeast surface display platform. The N-terminal fusion partner is based on a-agglutinin, and the C-terminal one is Flo1p. The yield of levan produced by these two whole-cell biocatalysts reaches 26 g/L and 34 g/L in 24 h, respectively. Meanwhile, the stability of the surface-displayed levansucrases is significantly enhanced. After six reuses, these two biocatalysts retained over 50% and 60% of their initial activities, respectively. Furthermore, the molecular weight and polydispersity test of the products suggested that the whole-cell biocatalyst of levansucrase displayed by Flo1p has more potentials in the production of levan with low molecular weight which is critical in certain applications. In conclusion, our method not only enable the possibility to reuse the enzyme, but also improves the stability of the enzyme.
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9
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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]
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10
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Abaramak G, Porras-Domínguez JR, Janse van Rensburg HC, Lescrinier E, Toksoy Öner E, Kırtel O, Van den Ende W. Functional and Molecular Characterization of the Halomicrobium sp. IBSBa Inulosucrase. Microorganisms 2021; 9:microorganisms9040749. [PMID: 33918392 PMCID: PMC8066391 DOI: 10.3390/microorganisms9040749] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 12/30/2022] Open
Abstract
Fructans are fructose-based (poly)saccharides with inulin and levan being the best-known ones. Thanks to their health-related benefits, inulin-type fructans have been under the focus of scientific and industrial communities, though mostly represented by plant-based inulins, and rarely by microbial ones. Recently, it was discovered that some extremely halophilic Archaea are also able to synthesize fructans. Here, we describe the first in-depth functional and molecular characterization of an Archaeal inulosucrase from Halomicrobium sp. IBSBa (HmcIsc). The HmcIsc enzyme was recombinantly expressed and purified in Escherichia coli and shown to synthesize inulin as proven by nuclear magnetic resonance (NMR) analysis. In accordance with the halophilic lifestyle of its native host, the enzyme showed maximum activity at very high NaCl concentrations (3.5 M), with specific adaptations for that purpose. Phylogenetic analyses suggested that Archaeal inulosucrases have been acquired from halophilic bacilli through horizontal gene transfer, with a HX(H/F)T motif evolving further into a HXHT motif, together with a unique D residue creating the onset of a specific alternative acceptor binding groove. This work uncovers a novel area in fructan research, highlighting unexplored aspects of life in hypersaline habitats, and raising questions about the general physiological relevance of inulosucrases and their products in nature.
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Affiliation(s)
- Gülbahar Abaramak
- IBSB-Industrial Biotechnology and Systems Biology Research Group, Bioengineering Department, Marmara University, Istanbul 34722, Turkey; (G.A.); (E.T.Ö.)
| | - Jaime Ricardo Porras-Domínguez
- Laboratory of Molecular Plant Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven, Belgium; (J.R.P.-D.); (H.C.J.v.R.)
| | | | - Eveline Lescrinier
- Laboratory for Medicinal Chemistry, Rega Institute for Medical Research, Herestraat 49, P.O. Box 1041, 3000 Leuven, Belgium;
| | - Ebru Toksoy Öner
- IBSB-Industrial Biotechnology and Systems Biology Research Group, Bioengineering Department, Marmara University, Istanbul 34722, Turkey; (G.A.); (E.T.Ö.)
| | - Onur Kırtel
- IBSB-Industrial Biotechnology and Systems Biology Research Group, Bioengineering Department, Marmara University, Istanbul 34722, Turkey; (G.A.); (E.T.Ö.)
- Correspondence: (O.K.); (W.V.d.E.)
| | - Wim Van den Ende
- Laboratory of Molecular Plant Biology, KU Leuven, Kasteelpark Arenberg 31, 3001 Leuven, Belgium; (J.R.P.-D.); (H.C.J.v.R.)
- Correspondence: (O.K.); (W.V.d.E.)
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11
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Sharipova MR, Mardanova AM, Rudakova NL, Pudova DS. Bistability and Formation of the Biofilm Matrix as Adaptive Mechanisms during the Stationary Phase of Bacillus subtilis. Microbiology (Reading) 2021. [DOI: 10.1134/s002626172006017x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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12
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Cheng R, Cheng L, Zhao Y, Wang L, Wang S, Zhang J. Biosynthesis and prebiotic activity of a linear levan from a new Paenibacillus isolate. Appl Microbiol Biotechnol 2021; 105:769-787. [PMID: 33404835 DOI: 10.1007/s00253-020-11088-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 12/16/2020] [Accepted: 12/28/2020] [Indexed: 02/08/2023]
Abstract
Levan, a type of β (2→6)-linked fructan, is a promising biopolymer with distinct properties and extensive applications in the fields of food, pharmaceutical, cosmetics, etc. However, the commercial availability of levan is still limited due to the relatively high production costs. Here, a new Paenibacillus sp. strain FP01 was isolated and identified as an efficient fructan producer with high yield (around 89.5 g/L fructan was obtained under 180 g/L sucrose) and conversation rate (49.7%). The fructan named Plev was structurally characterized as a linear levan-type fructan with a molecular mass of 3.11 × 106 Da. Aqueous solutions of Plev exhibited a non-Newtonian behavior at concentrations 3-5%. Heating and chilling had no obvious effects on apparent viscosities of Plev solutions. Plev also had good rheological stabilities toward pH (3-11) and metal salts (Na+, K+, Ca2+, Mg2+). Microbiome and metabolome analysis showed that Plev intervention increased the abundance of beneficial bacteria and elevated the levels of short-chain fatty acids (SCFAs) in feces of mice. Taken together, Plev could be considered a potential thickener and prebiotic supplement in food industry.Key points• Paenibacillus sp. strain FP01 was identified as a high-efficient levan producer.• The levan Plev from FP01 exhibited good rheological properties and stabilities.• The in vivo prebiotic activities of linear levan were revealed.
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Affiliation(s)
- Rui Cheng
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China
| | - Long Cheng
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China
| | - Yang Zhao
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China
| | - Lei Wang
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China
| | - Shiming Wang
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China
| | - Jianfa Zhang
- Center for Molecular Metabolism, Nanjing University of Science & Technology, 200 Xiaolingwei, Nanjing, 210094, China.
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13
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Gray DA, White JBR, Oluwole AO, Rath P, Glenwright AJ, Mazur A, Zahn M, Baslé A, Morland C, Evans SL, Cartmell A, Robinson CV, Hiller S, Ranson NA, Bolam DN, van den Berg B. Insights into SusCD-mediated glycan import by a prominent gut symbiont. Nat Commun 2021; 12:44. [PMID: 33398001 PMCID: PMC7782687 DOI: 10.1038/s41467-020-20285-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 11/19/2020] [Indexed: 01/29/2023] Open
Abstract
In Bacteroidetes, one of the dominant phyla of the mammalian gut, active uptake of large nutrients across the outer membrane is mediated by SusCD protein complexes via a "pedal bin" transport mechanism. However, many features of SusCD function in glycan uptake remain unclear, including ligand binding, the role of the SusD lid and the size limit for substrate transport. Here we characterise the β2,6 fructo-oligosaccharide (FOS) importing SusCD from Bacteroides thetaiotaomicron (Bt1762-Bt1763) to shed light on SusCD function. Co-crystal structures reveal residues involved in glycan recognition and suggest that the large binding cavity can accommodate several substrate molecules, each up to ~2.5 kDa in size, a finding supported by native mass spectrometry and isothermal titration calorimetry. Mutational studies in vivo provide functional insights into the key structural features of the SusCD apparatus and cryo-EM of the intact dimeric SusCD complex reveals several distinct states of the transporter, directly visualising the dynamics of the pedal bin transport mechanism.
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Affiliation(s)
- Declan A Gray
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Joshua B R White
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Abraham O Oluwole
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, UK
| | | | - Amy J Glenwright
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Adam Mazur
- Biozentrum, University of Basel, Basel, Switzerland
| | - Michael Zahn
- Biozentrum, University of Basel, Basel, Switzerland
| | - Arnaud Baslé
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Carl Morland
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Sasha L Evans
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Alan Cartmell
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Carol V Robinson
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, UK
| | | | - Neil A Ranson
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - David N Bolam
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
| | - Bert van den Berg
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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14
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Molecular weight dependent structure of the exopolysaccharide levan. Int J Biol Macromol 2020; 161:398-405. [DOI: 10.1016/j.ijbiomac.2020.06.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/26/2020] [Accepted: 06/02/2020] [Indexed: 11/22/2022]
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15
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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.
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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.
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16
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Ni D, Zhu Y, Xu W, Pang X, Lv J, Mu W. Production and Physicochemical Properties of Food-Grade High-Molecular-Weight Lactobacillus Inulin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:5854-5862. [PMID: 32366099 DOI: 10.1021/acs.jafc.9b07894] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Inulin has been widely applied in food, pharmaceuticals, and many other fields because of its versatile physicochemical properties and physiological functions. Previous research showed that inulosucrase from microorganisms could produce higher-molecular-weight inulin than vegetal inulin. Herein, a food-grade recombinant Bacillus subtilis expression system was constructed to produce inulosucrase from Lactobacillus gasseri DSM 20604 without antibiotic resistance genes. The produced inulosucrase was used to biosynthesize inulin with an average molecular weight of 5.8 × 106 Da. The physicochemical properties of the produced Lactobacillus inulin were evaluated including microstructure, thermal characteristics, crystallinity, rheological behaviors, and storage stability. By comparing with vegetal inulin and other polymers, the biosynthesized microbial inulin showed some superior properties, such as better gel-forming capability and storage stability in aqueous solution than vegetal inulin. These results opened up possibilities for further investigations aimed at developing microbial inulin in the food industry.
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Affiliation(s)
- Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yingying Zhu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Xiaoyang Pang
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Jiaping Lv
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs/Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu 214122, China
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17
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Bouallegue A, Casillo A, Chaari F, Cimini D, Corsaro MM, Bachoual R, Ellouz-Chaabouni S. Statistical optimization of levan: Influence of the parameter on levan structure and angiotensin I-converting enzyme inhibitory. Int J Biol Macromol 2020; 158:945-952. [PMID: 32360961 DOI: 10.1016/j.ijbiomac.2020.04.232] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/24/2020] [Accepted: 04/26/2020] [Indexed: 10/24/2022]
Abstract
Based on Plackett-Burman design, steepest ascent method, and Box-Behnken design, statistical optimization for B. subtilis AF17 for levan production was carried out. Sucrose, tryptone and initial pH were found to be the most significant parameter (P < 0.05) for levan production. Result showed that the optimum condition was sucrose 162.5 g/L, tryptone 10 g/L, initial pH 7 and maximum yield was 7.9 ± 0.18 g/L in 72 h fermentation. Purified levan was characterized using various physicochemical techniques such as GC-MS, 1H NMR, 13C NMR spectroscopy and SEC/TDA. Based on this data, the structure of levan was independent of initial culture conditions. The biomedical potential of the isolated Bacillus subtilis A17 levan for its angiotensin-I converting enzyme (ACE) inhibition activities was exploited in vitro. Interestingly, levan possessed an important angiotensin I converting enzyme (ACE) inhibitory 81.1 ± 4.1% at 4 mg/mL. The overall, data suggested that levan presents a promising natural source of antihypertensive agents.
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Affiliation(s)
- Amir Bouallegue
- Laboratory for the Improvement of Plants and Valorization of Agroressources, National School of Engineering of Sfax (ENIS), University of Sfax, Sfax 3038, Tunisia; Faculty of Sciences of Gabes, University of Gabes, Gabes, Tunisia.
| | - Angela Casillo
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, via Cintia 4, I-80126 Napoli, Italy
| | - Fatma Chaari
- Laboratory for the Improvement of Plants and Valorization of Agroressources, National School of Engineering of Sfax (ENIS), University of Sfax, Sfax 3038, Tunisia
| | - Donatella Cimini
- Department of Experimental Medicine, Section of Biotechnology, University of Campania "Luigi Vanvitelli", via de Crecchio 7, I-80138 Napoli, Italy
| | - Maria Michela Corsaro
- Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, via Cintia 4, I-80126 Napoli, Italy
| | - Rafik Bachoual
- Laboratory for the Improvement of Plants and Valorization of Agroressources, National School of Engineering of Sfax (ENIS), University of Sfax, Sfax 3038, Tunisia; Faculty of Sciences of Gabes, University of Gabes, Gabes, Tunisia
| | - Semia Ellouz-Chaabouni
- Laboratory for the Improvement of Plants and Valorization of Agroressources, National School of Engineering of Sfax (ENIS), University of Sfax, Sfax 3038, Tunisia; Common Service Unit of Bioreactor Coupled with an Ultrafilter, National School of Engineering, Sfax University, P.O. Box 1173, 3038 Sfax, Tunisia.
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18
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Shimizu N, Abea A, Ushiyama T, Toksoy Öner E. Effect of temperature on the hydrolysis of levan treated with compressed hot water fluids. Food Sci Nutr 2020; 8:2004-2014. [PMID: 32328267 PMCID: PMC7174225 DOI: 10.1002/fsn3.1488] [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: 03/06/2019] [Revised: 12/27/2019] [Accepted: 01/31/2020] [Indexed: 11/11/2022] Open
Abstract
The hydrolysis of levan using compressed hot water for the production of functional fructooligosaccharides (FOSs) was investigated. Levans from Erwinia herbicola (EH) and Halomonas smyrnensis (HS) were characterized using scanning electron microscopy and light scattering techniques, and hydrolyzed using compressed hot water at four temperatures (120, 140, 160, and 180°C). The hydrolysates were analyzed using high-performance liquid chromatography and electrospray ionization-mass spectrometry. Levan HS showed a crystalline morphology, whereas levan EH showed an aggregated structure. Both levans had molar masses on the order of 106 g/mol, but levan EH had a smaller radius of gyration, hydrodynamic radius, and intrinsic viscosity. Levan EH hydrolyzed into FOSs at approximately 120°C, whereas levan HS required a temperature of at least 160°C, possibly because of differences in the degree of branching of the two levans. Both samples were degraded to fructose when treated at 180°C.
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Affiliation(s)
- Naoto Shimizu
- Research Faculty of AgricultureHokkaido UniversitySapporoJapan
- Field Science Center for Northern BiosphereHokkaido UniversitySapporoJapan
| | - Andres Abea
- Graduate School of AgricultureHokkaido UniversitySapporoJapan
| | | | - Ebru Toksoy Öner
- Department of BioengineeringIBSBMarmara UniversityIstanbulTurkey
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19
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Hundschell C, Bäther S, Drusch S, Wagemans A. Osmometric and viscometric study of levan, β-lactoglobulin and their mixtures. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2019.105580] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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20
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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.
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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;
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21
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Liu C, Kolida S, Charalampopoulos D, Rastall RA. An evaluation of the prebiotic potential of microbial levans from Erwinia sp. 10119. J Funct Foods 2020. [DOI: 10.1016/j.jff.2019.103668] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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22
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Kırtel O, Lescrinier E, Van den Ende W, Toksoy Öner E. Discovery of fructans in Archaea. Carbohydr Polym 2019; 220:149-156. [DOI: 10.1016/j.carbpol.2019.05.064] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/22/2019] [Accepted: 05/22/2019] [Indexed: 02/07/2023]
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23
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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]
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24
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Gojgic-Cvijovic G, Jakovljevic D, Loncarevic B, Todorovic N, Pergal M, Ciric J, Loos K, Beskoski V, Vrvic M. Production of levan by Bacillus licheniformis NS032 in sugar beet molasses-based medium. Int J Biol Macromol 2019; 121:142-151. [DOI: 10.1016/j.ijbiomac.2018.10.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 09/25/2018] [Accepted: 10/02/2018] [Indexed: 10/28/2022]
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25
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Peng J, Xu W, Ni D, Zhang W, Zhang T, Guang C, Mu W. Preparation of a novel water-soluble gel from Erwinia amylovora levan. Int J Biol Macromol 2018; 122:469-478. [PMID: 30342147 DOI: 10.1016/j.ijbiomac.2018.10.093] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/01/2018] [Accepted: 10/14/2018] [Indexed: 02/04/2023]
Abstract
Less attention has been focused on the industrial applications of levan-type fructan than that of inulin. Levan-type fructan is a unique homopolysaccharide consisting of fructose residues with a β-(2, 6) linkage that possesses unique physiochemical properties such as low intrinsic viscosity. In this study, the recombinant levansucrase from Erwinia amylovora was used to efficiently produce levan from sucrose, and under optimised conditions, 195 g/L levan was produced from 500 g/L sucrose, with the highest conversion rate of 59%. The physicochemical properties of E. amylovora levan, such as surface morphology, thermal behaviour, rheology behaviour and texture analysis, were evaluated and compared with those of commercial gels, including xanthan, guar, carrageenan and Arabic gums. The produced E. amylovora levan showed a series of acceptable physicochemical properties, indicating a potential application for levan as a novel water-soluble micro gel. The conclusions of this study support the exploration of the use of more hydrogels in the food, medicinal and cosmetic industries.
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Affiliation(s)
- Jiaying Peng
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Tao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
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26
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La China S, Zanichelli G, De Vero L, Gullo M. Oxidative fermentations and exopolysaccharides production by acetic acid bacteria: a mini review. Biotechnol Lett 2018; 40:1289-1302. [DOI: 10.1007/s10529-018-2591-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/03/2018] [Indexed: 02/07/2023]
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27
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Lee SY, Shin WR, Sekhon SS, Lee JP, Kim YC, Ahn JY, Kim YH. Molecular Docking Analysis and Biochemical Evaluation of Levansucrase from Sphingobium chungbukense DJ77. ACS COMBINATORIAL SCIENCE 2018; 20:414-422. [PMID: 29812898 DOI: 10.1021/acscombsci.8b00002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacterial exopolymer Levan (β-(2,6) polyfructan) synthesized by levansucrase has attracted interest for various applications due to its low intrinsic viscosity compared with other polysaccharides. We report a novel levansucrase (Lsc) isolated from Sphingobium chunbukense DJ77 and verify its biochemical characteristics by comparative analysis of molecular docking analysis (MOE) and catalytic residue analysis. The complete sequence of the Lsc encoding gene ( lsc) was cloned under the direction of the T7 promoter and purified in an Escherichia coli BL21 (DE3) protein expression system. The enzyme activity analysis and ligand docking MOE study of S. chungbukense DJ77 Lsc revealed that Arg 77, Ser112, Arg 195, Asp196, Glu257, and Gln275 were involved in the sucrose binding and splitting as well as transfructosylation activity. A catalytic comparison of Lsc of S. chungbukense DJ77 with the results of site-directed mutational analysis indicated that Gln275 may coordinate a favorable substrate binding environment, offering broad pH resistance in the range of 5-10. The results suggest that the recombinant E. coli carrying S. chungbukense DJ77 Lsc might produce levan under the regular growth conditions with less need for pH manipulation.
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Affiliation(s)
- Soo Youn Lee
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
- Climate Change Research Division, Korea Institute of Energy Research, 152 Gajeong-Ro, Yuseong-Gu, Daejeon 34129, Korea
| | - Woo-Ri Shin
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
| | - Simranjeet Singh Sekhon
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
| | - Jin-Pyo Lee
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
| | - Young-Chang Kim
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
| | - Ji-Young Ahn
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
| | - Yang-Hoon Kim
- School of Biological Sciences, Chungbuk National University, 1 Chungdae-Ro, Seowon-Gu, Cheongju 28644, Korea
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28
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Physicochemical properties of a high molecular weight levan from Brenneria sp. EniD312. Int J Biol Macromol 2018; 109:810-818. [DOI: 10.1016/j.ijbiomac.2017.11.056] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/24/2017] [Accepted: 11/09/2017] [Indexed: 01/12/2023]
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Versluys M, Kirtel O, Toksoy Öner E, Van den Ende W. The fructan syndrome: Evolutionary aspects and common themes among plants and microbes. PLANT, CELL & ENVIRONMENT 2018; 41:16-38. [PMID: 28925070 DOI: 10.1111/pce.13070] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 08/30/2017] [Accepted: 09/09/2017] [Indexed: 05/13/2023]
Abstract
Fructans are multifunctional fructose-based water soluble carbohydrates found in all biological kingdoms but not in animals. Most research has focused on plant and microbial fructans and has received a growing interest because of their practical applications. Nevertheless, the origin of fructan production, the so-called "fructan syndrome," is still unknown. Why fructans only occur in a limited number of plant and microbial species remains unclear. In this review, we provide an overview of plant and microbial fructan research with a focus on fructans as an adaptation to the environment and their role in (a)biotic stress tolerance. The taxonomical and biogeographical distribution of fructans in both kingdoms is discussed and linked (where possible) to environmental factors. Overall, the fructan syndrome may be related to water scarcity and differences in physicochemical properties, for instance, water retaining characteristics, at least partially explain why different fructan types with different branching levels are found in different species. Although a close correlation between environmental stresses and fructan production is quite clear in plants, this link seems to be missing in microbes. We hypothesize that this can be at least partially explained by differential evolutionary timeframes for plants and microbes, combined with potential redundancy effects.
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Affiliation(s)
- Maxime Versluys
- Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium
| | - Onur Kirtel
- Industrial Biotechnology and Systems Biology Research Group, Bioengineering Department, Marmara University, Istanbul, 34722, Turkey
| | - Ebru Toksoy Öner
- Industrial Biotechnology and Systems Biology Research Group, Bioengineering Department, Marmara University, Istanbul, 34722, Turkey
| | - Wim Van den Ende
- Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium
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30
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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.
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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
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31
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Ua-Arak T, Jakob F, Vogel RF. Influence of levan-producing acetic acid bacteria on buckwheat-sourdough breads. Food Microbiol 2017; 65:95-104. [DOI: 10.1016/j.fm.2017.02.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 11/28/2022]
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Ua-Arak T, Jakob F, Vogel RF. Fermentation pH Modulates the Size Distributions and Functional Properties of Gluconobacter albidus TMW 2.1191 Levan. Front Microbiol 2017; 8:807. [PMID: 28522999 PMCID: PMC5415625 DOI: 10.3389/fmicb.2017.00807] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/19/2017] [Indexed: 11/13/2022] Open
Abstract
Bacterial levan has gained an increasing interest over the last decades due to its unique characteristics and multiple possible applications. Levan and other exopolysaccharides (EPSs) production are usually optimized to obtain the highest concentration or yield while a possible change of the molecular size and mass during the production process is mostly neglected. In this study, the molar mass and radius of levan samples were monitored during fermentations with the food-grade, levan-producing acetic acid bacterium Gluconobacter (G.) albidus TMW 2.1191 in shake flasks (without pH control) and bioreactors (with pH control at 4.5, 5.5 and 6.5, respectively). In uncontrolled fermentations, the levan size/molar mass continuously decreased concomitantly with the continuous acidification of the nutrient medium. On the contrary, the amount, molar mass and size of levan could be directly influenced by controlling the pH during fermentation. Using equal initial substrate amounts, the largest weight average molar mass and geometric radius of levan were observed at constant pH 6.5, while the highest levan concentration was obtained at constant pH 4.5. Since there is a special demand to find suitable hydrocolloids from food-grade bacteria to develop novel gluten-free (GF) products, these differently produced levans were used for baking of GF breads, and the best quality improvement was obtained by addition of levan with the highest mass and radius. This work, therefore, demonstrates for the first time that one bacterial strain can produce specific high molecular weight fractions of one EPS type, which differ in properties and sizes among each other in dependence of the controllable production conditions.
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Affiliation(s)
- Tharalinee Ua-Arak
- Lehrstuhl für Technische Mikrobiologie, Technische Universität MünchenFreising, Germany
| | - Frank Jakob
- Lehrstuhl für Technische Mikrobiologie, Technische Universität MünchenFreising, Germany
| | - Rudi F Vogel
- Lehrstuhl für Technische Mikrobiologie, Technische Universität MünchenFreising, Germany
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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.
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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
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Liu Q, Yu S, Zhang T, Jiang B, Mu W. Efficient biosynthesis of levan from sucrose by a novel levansucrase from Brenneria goodwinii. Carbohydr Polym 2017; 157:1732-1740. [DOI: 10.1016/j.carbpol.2016.11.057] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 11/16/2016] [Accepted: 11/19/2016] [Indexed: 10/20/2022]
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Mardo K, Visnapuu T, Vija H, Aasamets A, Viigand K, Alamäe T. A Highly Active Endo-Levanase BT1760 of a Dominant Mammalian Gut Commensal Bacteroides thetaiotaomicron Cleaves Not Only Various Bacterial Levans, but Also Levan of Timothy Grass. PLoS One 2017; 12:e0169989. [PMID: 28103254 PMCID: PMC5245892 DOI: 10.1371/journal.pone.0169989] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/27/2016] [Indexed: 12/11/2022] Open
Abstract
Bacteroides thetaiotaomicron, an abundant commensal of the human gut, degrades numerous complex carbohydrates. Recently, it was reported to grow on a β-2,6-linked polyfructan levan produced by Zymomonas mobilis degrading the polymer into fructooligosaccharides (FOS) with a cell surface bound endo-levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3 of Pseudomonas syringae pv. tomato, its mutant Asp300Asn, levansucrases of Zymomonas mobilis, Erwinia herbicola, Halomonas smyrnensis as well as on levan isolated from timothy grass. For the first time a plant levan is shown as a perfect substrate for an endo-fructanase of a human gut bacterium. BT1760 degraded levans to FOS with degree of polymerization from 2 to 13. At optimal reaction conditions up to 1 g of FOS were produced per 1 mg of BT1760 protein. Low molecular weight (<60 kDa) levans, including timothy grass levan and levan synthesized from sucrose by the Lsc3Asp300Asn, were degraded most rapidly whilst levan produced by Lsc3 from raffinose least rapidly. BT1760 catalyzed finely at human body temperature (37°C) and in moderately acidic environment (pH 5–6) that is typical for the gut lumen. According to differential scanning fluorimetry, the Tm of the endo-levanase was 51.5°C. All tested levans were sufficiently stable in acidic conditions (pH 2.0) simulating the gastric environment. Therefore, levans of both bacterial and plant origin may serve as a prebiotic fiber for B. thetaiotaomicron and contribute to short-chain fatty acids synthesis by gut microbiota. In the genome of Bacteroides xylanisolvens of human origin a putative levan degradation locus was disclosed.
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Affiliation(s)
- Karin Mardo
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Triinu Visnapuu
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Heiki Vija
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - Anneli Aasamets
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Katrin Viigand
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Tiina Alamäe
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- * E-mail:
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Benigar E, Zupančič Valant A, Dogsa I, Sretenovic S, Stopar D, Jamnik A, Tomšič M. Structure and Dynamics of a Model Polymer Mixture Mimicking a Levan-Based Bacterial Biofilm of Bacillus subtilis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:8182-8194. [PMID: 27438223 DOI: 10.1021/acs.langmuir.6b02041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this paper, we report on the structure and dynamics of biologically important model polymer mixtures that mimic the extracellular polymeric matrix in native biofilm of Bacillus subtilis. This biofilm is rich in nonionic polysaccharide levan, but also contains other biopolymers such as DNA and proteins in small concentrations. Aiming to identify the contribution of each component to the formation of the biofilm, our investigations encompassed dynamic rheology, small-angle X-ray scattering, dynamic light scattering, microscopy, densitometry, and sound velocity measurements. As it turned out, this very powerful combination of techniques is able to provide solid results on the dynamical and structural aspects of the microbiologically and chemically complex biofilm formations. Macroscopic rheological measurements revealed that the addition of DNA to levan solution increased the viscosity, pseudoplasticity, and elasticity of the system. The addition of protein contributed similarly, but also increased the rigidity of the system. This confirms that the presence of minor biofilm components is essential for biofilm formation. DNA and proteins appear to confine levan molecules within their supramolecular structure and, in this way, restrict the role of levan to merely a filling agent. These findings were complemented by small-angle X-ray scattering data, which provided insight into the structure on a molecular scale. One of the essential goals of this work was to compare the structural properties of the native biofilm and synthetic biofilm mixture.
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Affiliation(s)
- Elizabeta Benigar
- Faculty of Chemistry and Chemical Technology and Biotechnical Faculty, University of Ljubljana , Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Andreja Zupančič Valant
- Faculty of Chemistry and Chemical Technology and Biotechnical Faculty, University of Ljubljana , Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Iztok Dogsa
- Biotechnical Faculty, University of Ljubljana , Večna pot 111, SI-1000, Ljubljana, Slovenia
| | - Simon Sretenovic
- Biotechnical Faculty, University of Ljubljana , Večna pot 111, SI-1000, Ljubljana, Slovenia
| | - David Stopar
- Biotechnical Faculty, University of Ljubljana , Večna pot 111, SI-1000, Ljubljana, Slovenia
| | - Andrej Jamnik
- Faculty of Chemistry and Chemical Technology and Biotechnical Faculty, University of Ljubljana , Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Matija Tomšič
- Faculty of Chemistry and Chemical Technology and Biotechnical Faculty, University of Ljubljana , Večna pot 113, SI-1000 Ljubljana, Slovenia
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Stojković B, Sretenovic S, Dogsa I, Poberaj I, Stopar D. Viscoelastic properties of levan-DNA mixtures important in microbial biofilm formation as determined by micro- and macrorheology. Biophys J 2015; 108:758-65. [PMID: 25650942 DOI: 10.1016/j.bpj.2014.10.072] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 10/14/2014] [Accepted: 10/30/2014] [Indexed: 12/12/2022] Open
Abstract
We studied the viscoelastic properties of homogeneous and inhomogeneous levan-DNA mixtures using optical tweezers and a rotational rheometer. Levan and DNA are important components of the extracellular matrix of bacterial biofilms. Their viscoelastic properties influence the mechanical as well as molecular-transport properties of biofilm. Both macro- and microrheology measurements in homogeneous levan-DNA mixtures revealed pseudoplastic behavior. When the concentration of DNA reached a critical value, levan started to aggregate, forming clusters of a few microns in size. Microrheology using optical tweezers enabled us to measure local viscoelastic properties within the clusters as well as in the DNA phase surrounding the levan aggregates. In phase-separated levan-DNA mixtures, the results of macro- and microrheology differed significantly. The local viscosity and elasticity of levan increased, whereas the local viscosity of DNA decreased. On the other hand, the results of bulk viscosity measurements suggest that levan clusters do not interact strongly with DNA. Upon treatment with DNase, levan aggregates dispersed. These results demonstrate the advantages of microrheological measurements compared to bulk viscoelastic measurements when the materials under investigation are complex and inhomogeneous, as is often the case in biological samples.
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Affiliation(s)
- Biljana Stojković
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia
| | - Simon Sretenovic
- Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Iztok Dogsa
- Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Igor Poberaj
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia
| | - David Stopar
- Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
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Recent novel applications of levansucrases. Appl Microbiol Biotechnol 2015; 99:6959-69. [DOI: 10.1007/s00253-015-6797-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 01/12/2023]
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Cairns LS, Hobley L, Stanley-Wall NR. Biofilm formation by Bacillus subtilis: new insights into regulatory strategies and assembly mechanisms. Mol Microbiol 2014; 93:587-98. [PMID: 24988880 PMCID: PMC4238804 DOI: 10.1111/mmi.12697] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2014] [Indexed: 12/16/2022]
Abstract
Biofilm formation is a social behaviour that generates favourable conditions for sustained survival in the natural environment. For the Gram-positive bacterium Bacillus subtilis the process involves the differentiation of cell fate within an isogenic population and the production of communal goods that form the biofilm matrix. Here we review recent progress in understanding the regulatory pathways that control biofilm formation and highlight developments in understanding the composition, function and structure of the biofilm matrix.
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Affiliation(s)
- Lynne S Cairns
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
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