51
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Functional characterisation of potato starch modified by specific in planta alteration of the amylopectin branching and phosphate substitution. Food Hydrocoll 2005. [DOI: 10.1016/j.foodhyd.2005.01.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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52
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Blennow A, Wischmann B, Houborg K, Ahmt T, Jørgensen K, Engelsen SB, Bandsholm O, Poulsen P. Structure function relationships of transgenic starches with engineered phosphate substitution and starch branching. Int J Biol Macromol 2005; 36:159-68. [PMID: 16024070 DOI: 10.1016/j.ijbiomac.2005.05.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Revised: 05/20/2005] [Accepted: 05/21/2005] [Indexed: 11/29/2022]
Abstract
Potato tuber starch was genetically engineered in the plant by the simultaneous antisense suppression of the starch branching enzyme (SBE) I and II isoforms. Starch prepared from 12 independent lines and three control lines were characterised with respect to structural and physical properties. The lengths of the amylopectin unit chains, the concentrations of amylose and monoesterified phosphate were significantly increased in the transgenically engineered starches. Size exclusion chromatography with refractive index detection (SEC-RI) indicated a minor decrease in apparent molecular size of the amylose and the less branched amylopectin fractions. Differential scanning calorimetry (DSC) revealed significantly higher peak temperatures for gelatinisation and retrogradation of the genetically engineered starches whereas the enthalpies of gelatinisation were lower. Aqueous gels prepared from the transgenic starches showed increased gel elasticity and viscosity. Principle component analysis (PCA) of the data set discriminated the control lines from the transgenic lines and revealed a high correlation between phosphate concentration and amylopectin unit chain length. The PCA also indicated that the rheological characteristics were primarily influenced by the amylose concentration. The phosphate and the amylopectin unit chain lengths had influenced primarily the pasting and rheological properties of the starch gels.
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Affiliation(s)
- Andreas Blennow
- Plant Biochemistry Laboratory, Department Plant Biology, Center for Plant Molecular Physiology (PlaCe), Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
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53
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Blennow A, Sjöland AK, Andersson R, Kristiansson P. The distribution of elements in the native starch granule as studied by particle-induced X-ray emission and complementary methods. Anal Biochem 2005; 347:327-9. [PMID: 16289081 DOI: 10.1016/j.ab.2005.06.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 06/06/2005] [Accepted: 06/07/2005] [Indexed: 11/23/2022]
Affiliation(s)
- Andreas Blennow
- Center for Molecular Plant Physiology, Plant Biochemistry Laboratory, Department of Plant Biology, The Royal Veterinary and Agricultural University, 40 Thorvaldsensvej, DK-1871 Fredriksberg C, Copenhagen, Denmark.
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54
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Bertolini AC, Creamer LK, Eppink M, Boland M. Some rheological properties of sodium caseinate-starch gels. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:2248-2254. [PMID: 15769164 DOI: 10.1021/jf048656p] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The influence of sodium caseinate on the thermal and rheological properties of starch gels at different concentrations and from different botanical sources was evaluated. In sodium caseinate-starch gels, for all starches with the exception of potato starch, the sodium caseinate promoted an increase in the storage modulus and in the viscosity of the composite gel when compared with starch gels. The addition of sodium caseinate resulted in an increase in the onset temperature, the gelatinization temperature, and the end temperature, and there was a significant interaction between starch and sodium caseinate for the onset temperature, the peak temperature, and the end temperature. Microscopy results suggested that sodium caseinate promoted an increase in the homogeneity in the matrix of cereal starch gels.
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Affiliation(s)
- Andrea C Bertolini
- Fonterra Research Centre, Private Bag 11 029, Dairy Farm Road, Palmerston North, New Zealand.
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55
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van Hijum SAFT, Szalowska E, van der Maarel MJEC, Dijkhuizen L. Biochemical and molecular characterization of a levansucrase from Lactobacillus reuteri. Microbiology (Reading) 2004; 150:621-630. [PMID: 14993311 DOI: 10.1099/mic.0.26671-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lactobacillus reuteri strain 121 employs a fructosyltransferase (FTF) to synthesize a fructose polymer [a fructan of the levan type, with beta(2-->6) linkages] from sucrose or raffinose. Purification of this FTF (a levansucrase), and identification of peptide amino acid sequences, allowed isolation of the first Lactobacillus levansucrase gene (lev), encoding a protein (Lev) consisting of 804 amino acids. Lev showed highest similarity with an inulosucrase of L. reuteri 121 [Inu; producing an inulin polymer with beta(2-->1)-linked fructosyl units] and with FTFs from streptococci. Expression of lev in Escherichia coli resulted in an active FTF (Lev Delta 773His) that produced the same levan polymer [with only 2-3 % beta(2-->1-->6) branching points] as L. reuteri 121 cells grown on raffinose. The low degree of branching of the L. reuteri levan is very different from bacterial levans known up to now, such as that of Streptococcus salivarius, having up to 30 % branches. Although Lev is unusual in showing a higher hydrolysis than transferase activity, significant amounts of levan polymer are produced both in vivo and in vitro. Lev is strongly dependent on Ca(2+) ions for activity. Unique properties of L. reuteri Lev together with Inu are: (i) the presence of a C-terminal cell-wall-anchoring motif causing similar expression problems in Escherichia coli, (ii) a relatively high optimum temperature for activity for FTF enzymes, and (iii) at 50 degrees C, kinetics that are best described by the Hill equation.
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Affiliation(s)
- S A F T van Hijum
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
- Centre for Carbohydrate Bioengineering, TNO-RUG, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - E Szalowska
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
- Centre for Carbohydrate Bioengineering, TNO-RUG, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - M J E C van der Maarel
- Innovative Ingredients and Products Department, TNO Nutrition and Food Research, Rouaanstraat 27, 9723 CC Groningen, The Netherlands
- Centre for Carbohydrate Bioengineering, TNO-RUG, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - L Dijkhuizen
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
- Centre for Carbohydrate Bioengineering, TNO-RUG, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
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56
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Yanagisawa T, Kiribuchi-Otobe C, Fujita M. Increase in Apparent Amylose Content and Change in Starch Pasting Properties at Cool Growth Temperatures in Mutant Wheat. Cereal Chem 2004. [DOI: 10.1094/cchem.2004.81.1.26] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- T. Yanagisawa
- National Institute of Crop Science (NICS), 2-1-18 Kannondai, Tsukuba, Ibaraki 305-8518, Japan
- Present address of corresponding author: National Agricultural Research Center for Western Region (WeNarc); 1-3-1 Senyu, Zentsuji, Kagawa 765-8508, Japan. Fax: +81-877-63-1683. E-mail:
| | - C. Kiribuchi-Otobe
- National Institute of Crop Science (NICS), 2-1-18 Kannondai, Tsukuba, Ibaraki 305-8518, Japan
| | - M. Fujita
- National Institute of Crop Science (NICS), 2-1-18 Kannondai, Tsukuba, Ibaraki 305-8518, Japan
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57
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Grcev S, Schoenmakers P, Iedema P. Determination of molecular weight and size distribution and branching characteristics of PVAc by means of size exclusion chromatography/multi-angle laser light scattering (SEC/MALLS). POLYMER 2004. [DOI: 10.1016/j.polymer.2003.10.077] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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58
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Blennow A, Hansen M, Schulz A, Jørgensen K, Donald AM, Sanderson J. The molecular deposition of transgenically modified starch in the starch granule as imaged by functional microscopy. J Struct Biol 2003; 143:229-41. [PMID: 14572478 DOI: 10.1016/j.jsb.2003.08.009] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The molecular deposition of starch extracted from normal plants and transgenically modified potato lines was investigated using a combination of light microscopy, environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CLSM). ESEM permitted the detailed (10 nm) topographical analysis of starch granules in their hydrated state. CLSM could reveal internal molar deposition patterns of starch molecules. This was achieved by equimolar labelling of each starch molecule using the aminofluorophore 8-amino-1,3,6-pyrenetrisulfonic acid (APTS). Starch extracted from tubers with low amylose contents (suppressed granule bound starch synthase, GBSS) showed very little APTS fluorescence and starch granules with low molecular weight amylopectin and/or high amylose contents showed high fluorescence. Growth ring structures were sharper in granules with normal or high amylose contents. High amylose granules showed a relatively even distribution in fluorescence while normal and low amylose granules had an intense fluorescence in the hilum indicating a high concentration of amylose in the centre of the granule. Antisense of the starch phosphorylating enzyme (GWD) resulted in low molecular weight amylopectin and small fissures in the granules. Starch granules with suppressed starch branching enzyme (SBE) had severe cracks and rough surfaces. Relationships between starch molecular structure, nano-scale crystalline arrangements and topographical-morphological features were estimated and discussed.
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Affiliation(s)
- Andreas Blennow
- Center for Molecular Plant Physiology, Plant Biochemistry Laboratory, Department of Plant Biology, The Royal Veterinary and Agricultural University, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark.
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59
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Andersson M, Wittgren B, Wahlund KG. Accuracy in Multiangle Light Scattering Measurements for Molar Mass and Radius Estimations. Model Calculations and Experiments. Anal Chem 2003; 75:4279-91. [PMID: 14632147 DOI: 10.1021/ac030128+] [Citation(s) in RCA: 212] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Multiangle light scattering (MALS) is a well-established technique used to determine the size of macromolecules and particles. In this study, different extrapolation procedures used in MALS were investigated with regard to accuracy and robustness in the obtained molar mass and rms radius. Three different mathematical transformations of the light scattering function referred to as the Debye, Zimm, and Berry methods for constructing the Debye plot were investigated for two idealized polymer shapes, homogeneous spheres and random coils, with radii from 25 to 250 nm. The effect of the angular interval used for the extrapolation was investigated, as was the robustness of the different transformations toward errors in the measured light scattering intensity at low angles. For an rms radius less than 50 nm, the relative error in molar mass due to extrapolation was less than 1% independent of the method used. For larger radii, the error increased and the extrapolation procedure became more critical. For random coil polymers, the Berry method was superior in terms of accuracy and robustness. For spheres, the Debye method was superior. The Zimm method was inferior to the others. The different extrapolation methods were evaluated and compared on experimental data from a size exclusion chromatography-MALS analysis of an ultrahigh molar mass poly(ethylene oxide) (PEO). The PEO data qualitatively verified the calculations and stressed the importance of optimizing the extrapolation procedure after careful evaluation of the experimental data. A discussion of how to detect erroneous data in an experimental Debye plot is given.
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Affiliation(s)
- Mats Andersson
- Department of Technical Analytical Chemistry, Center for Chemistry and Chemical Engineering, Lund University, Box 124, SE-221 00 Lund, Sweden
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60
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Viksø-Nielsen A, Blennow A, Jørgensen K, Kristensen KH, Jensen A, Møller BL. Structural, physicochemical, and pasting properties of starches from potato plants with repressed r1-gene. Biomacromolecules 2002; 2:836-43. [PMID: 11710039 DOI: 10.1021/bm0155165] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of this work was to investigate the effect on starch molecular and physicochemical properties of down regulation of the R1 protein in potato (Solanum tuberosum L. cv. "Dianella") tubers. Most prominent is a 90% suppression of the phosphate content in the isolated potato tuber starch. The amylopectin chain length distribution profile as determined by HPAEC/PAD was not affected, but the amylose content was increased in the most down-regulated plants. The pasting properties of the transgenic starch revealed a pronounced decrease in peak viscosity and increased setback viscosity as measured using a rapid Visco analyzer. The starch gels displayed an increased hardness and stickiness with a maximum at 1.7 nmol of Glc-6P mg-1 of starch compared to the control lines. At very low phosphate levels (1.4 nmol of Glc-6P mg-1 of starch), the gel hardness was decreased as a result of increased gel brittleness. The increase in gel brittleness is believed to be an effect of an increased proportion of free amylopectin blocklets in the starch as determined by SEC/RI. The possible links between the structural and physicochemical parameters are discussed.
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Affiliation(s)
- A Viksø-Nielsen
- Plant Biochemistry Laboratory, Department of Plant Biology, Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
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61
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Girod S, Baldet-Dupy P, Maillols H, Devoisselle JM. On-line direct determination of the second virial coefficient of a natural polysaccharide using size-exclusion chromatography and multi-angle laser light scattering. J Chromatogr A 2002; 943:147-52. [PMID: 11820275 DOI: 10.1016/s0021-9673(01)01415-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
By combining a size-exclusion chromatographic (SEC) separation and an on-line multi-angle light scattering (MALLS) analysis, we have elaborated an original methodology permitting on-line direct determination of the second virial coefficient of molar mass fractions of polydisperse polysaccharides. By assimilating the SEC-MALLS data to a batch mode acquisition, we have obtained on-line the complete Zimm plot of the eluted fractions, leading to knowledge of their weight-average molar mass Mw, radius of gyration r(g) and second virial coefficient A2. Our methodology was successfully applied to a iota carrageenan sample in LiCl 100 mM, EDTA 1 g/l.
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Affiliation(s)
- S Girod
- Laboratoire Laphal, R&D, Allauch, France.
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