| 1. |
- Nahalka, J, et al.
(author)
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Elicitation of plumbagin by chitin and its release into the medium in Drosophyllum lusitanicum Link. suspension cultures
- 1998
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In: Biotechnology letters. - 0141-5492 .- 1573-6776. ; 20:9, s. 841-845
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Journal article (peer-reviewed)abstract
- Polysaccharides (chitin/pectin) that are involved in the interactions between plants and microorganisms were applied to the cultured cells of Drosophyllum lusitanicum. In the case of chitin addition, elicitation and crystallization of plumbagin in the medium were observed. N-Acetylchitooligosaccharides smaller than heptamers [(GlcNAc)(n) (n<7)] elicited the biosynthesis of plumbagin but did not increase the hypersensitive response (HR). On the other hand, carboxymethylchitin (DP similar to 200) led to the accumulation of plumbagin in cells and to HR death as well as to the lysis of the cells and release of plumbagin into the medium. The response of cultured cells to the N-Acetylchitosaccharides varied depending on the chemo/physiological conditions of the cells. Addition of pectin (1 g/l) resulted in enhanced HR and decreased biosynthesis of plumbagin.
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| 2. |
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| 3. |
- Hajduch, M, et al.
(author)
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An electrophoretic analysis of the seed protein body proteins from Pinus nigra
- 2001
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In: Biologia plantarum. - 0006-3134 .- 1573-8264. ; 44:1, s. 137-140
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Journal article (peer-reviewed)abstract
- Protein bodies (PBs) of European black pine (Pirus nigra Am.) were isolated from mature seeds. Extracted soluble matrix proteins and crystalloid proteins PBs proteins were investigated by SDS-PAGE electrophoresis in presence and absence of 2-mercaptoethanol. The proteins of molecular masses 16, 17, 18, 61 and 65 kDa were presented only in crystalloid protein samples. Only 15 kDa protein was present in soluble matrix proteins and not in crystalloid proteins. Another protein bands were present in both soluble matrix and crystalloid proteins. 20, 37, 38, 39 and 48 kDa proteins were strongly visible among crystalloid proteins. Bands of 23 and 32 kDa were more visible in soluble matrix protein samples. Different composition in crystalloid proteins was found in absence of 2-mercaptoethanol: no proteins with molecular mass 71 kDa and more proteins in soluble matrix. In case of crystalloid proteins we detected 7 protein bands in interval from 71 to 212 kDa.
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| 4. |
- Hrib, J, et al.
(author)
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Protein bodies in the pine megagametophyte in vitro culture : ultrastructural, histochemical and electrophoretic observations
- 2000
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In: Biologia plantarum. - 0006-3134 .- 1573-8264. ; 43:3, s. 329-336
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Journal article (peer-reviewed)abstract
- The megagametophytes of the European black pine (Pinus nigra Am.) were cultured on modified MS medium. After 10 d, protein bodies showed well-marked degradation on freeze-etched replicas and in preparations observed by scanning electron microscopy. After 20 d of cultivation, the megagametophyte cells were completely empty. Proteins secreted into the agar medium were determined by electrophoresis and 15 different proteins, in the range of 6.5 to 71 kDa, were identified.
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| 5. |
- Masarova, Jana, et al.
(author)
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Mannan-penicillin G acylase neoglycoproteins and their potential applications in biotechnology
- 2004
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In: Biotechnology and Applied Biochemistry. - 1470-8744. ; 39:3, s. 285-291
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Journal article (peer-reviewed)abstract
- Mannan-penicillin G acylase neoglycoproteins were prepared by the conjugation of Saccharomyces cerevisiae mannan with enzyme penicillin G acylase using the reductive amination method. Eight neoglycoproteins preparations were obtained after gel chromatography. The preparations contained from 42 to 67% (w/w) saccharides and their molar masses varied from 283 to over 1000 kDa. Significant biospecific interaction of separated fractions with the lectin concanavalin A was evaluated by the precipitation and sorption method (equilibrium constants) and further characterized using surface plasmon resonance to determine kinetic association and dissociation constants. K-D was determined over the range 10(-7) M. High-molar-mass preparations appeared to be more suitable for preparation of stable and active complexes with concanavalin A for prospective use as a penicillin G acylase biocatalyst in enzyme reactors. The enzyme stability of such complexes was significantly increased compared with the original neoglycoprotein. Lower-molar-mass preparations were more suitable for applications such as biocatalysts in bioanalytical devices.
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| 6. |
- Mislovicova, D, et al.
(author)
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Biospecific immobilization of mannan-penicillin G acylase neoglycoenzyme on Concanavalin A-bead cellulose
- 2004
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In: Journal of Biotechnology. - : Elsevier BV. - 1873-4863 .- 0168-1656. ; 110:1, s. 11-19
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Journal article (peer-reviewed)abstract
- The matter of this work was to evaluate possibilities of biospecific immobilization of synthetic mannan-penicillin G acylase neoglycoconjugate on Concanavalin A support. The conjugate containing 37% (w/w) of yeast mannan was prepared. Significant biospecific interaction of this neoglycoenzyme with Con A was confirmed by precipitation method. The biospecific sorption of conjugate was investigated using Concanavalin A-triazine bead celluloses MT-100 with different content of Con A (from 1.4 to 9.8 mg Con A/g wet support). The results obtained under optimal conditions were compared with those from covalent immobilization of PGA. The sorbent capacity was observed higher for covalent binding of enzyme. On the other hand, the biospecifically immobilized neoglycoenzyme retained a greater amount of initial activity. The maximum amount of 6.6 mg immobilized neoglycoenzyme/g wet Con A-sorbent (18.1 U/g) was achieved. The amount as well as activity of immobilized mannan-penicillin G acylase was increased by its two multiple layering on surface of sorbent (10.1 mg, respectively, 23.5 U/g wet sorbent). Determined storage and operational (using flow calorimetric method) stabilities of biospecifically immobilized enzyme, were similar, possibly somewhat higher that those of covalent bound penicillin G acylase. (C) 2004 Elsevier B.V. All rights reserved.
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| 7. |
- Mislovicova, D, et al.
(author)
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Influence of mannan epitopes in glycoproteins - Concanavalin A interaction. Comparison of natural and synthetic glycosylated proteins
- 2002
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In: International Journal of Biological Macromolecules. - 1879-0003. ; 30:5, s. 251-258
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Journal article (peer-reviewed)abstract
- Two natural glycoproteins/glycoenzymes, invertase and glucoamylase, and two neoglycoconjugates, synthetized from Saccharomyces cerevisiae mannan, bovine serum albumin and penicillin G acylase were tested for interaction with lectin Concanavalin A (Con A). The interaction of natural and synthetic glycoproteins with Con A was studied using three different experimental methods: (i) quantitative precipitation in solution (ii) sorption to Con A immobilized on bead cellulose; and (iii) kinetic measurement of the interaction by surface plasmon resonance. Prepared neoglycoproteins were further characterized: saccharide content, molecular weight, polydispersion, kinetic and equilibrium association constants with Con A were determined. It can be concluded that the used conjugation method proved to be able to produce neoglycoproteins with similar properties like natural glycoproteins, i.e. enzymatic activity (protein part) and lectin binding activity (mannan part) were preserved and the neoglycoconjugates interact with Con A similarly as natural mannan-type glycoproteins.
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| 8. |
- Mislovicova, D, et al.
(author)
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Neoglycoconjugates of mannan with bovine serum albumin and their interaction with lectin concanavalin A
- 2002
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In: Bioconjugate Chemistry. - : American Chemical Society (ACS). - 1520-4812 .- 1043-1802. ; 13:1, s. 136-142
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Journal article (peer-reviewed)abstract
- Neoglycoconjugates were prepared from mannan isolated from yeast Saccharomyces cerevisiae and activated by periodate oxidation to create aldehyde groups. Various degrees of oxidation introduced 11-28 aldehyde groups per mannan molecule and simultaneously resulted in a molar mass decrease from 46 to 44.5-31 kDa. The activated mannans were subsequently conjugated with bovine serum albumin forming neoglycoconjugates. Some parameters of these mannan-bovine serum albumin conjugates were characterized: saccharide content 25-30% w/w, molar mass within the range 169-246 kDa, and polydispersion (M-w/M-n) from 2.8 to 3.6. The interaction of these conjugates with lectin concanavalin A was studied using three different methods: W quantitative precipitation in solution; (ii) sorption to concanavalin A immobilized on bead cellulose; and (iii) kinetic measurement of the interaction by surface plasmon resonance. Quantitative precipitation assay showed only negligible differences in the precipitation course of original mannan and the corresponding mannan-bovine serum albumin conjugates. Both the sorption method (equilibrium method) and the surface plasmon resonance measurement (kinetic method) demonstrates that the values of dissociation constant K-D of all synthetic neoglycoconjugates were within the range 10(-7)-10(-8) mol.L-1 (close to K-D = 10(-1) mol-L-1 determined by the sorption method for the original mannan). In conclusion, characterization of synthetic neoglycoconjugates confirmed that the method used for their preparation retained the ability of mannan moiety to interact with concanavalin A.
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| 9. |
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| 10. |
- Nahálková, Jarmila, et al.
(author)
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Affinity analysis of lectin interaction with immobilized C- and O-gylcosides studied by surface plasmon resonance assay
- 2002
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In: Journal of Biochemical and Biophysical Methods. - 0165-022X .- 1872-857X. ; 52:1, s. 11-18
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Journal article (peer-reviewed)abstract
- A biosensor based on the surface plasmon resonance (SPR) principle was used for kinetic analysis of lectin interactions with different immobilized saccharide structures. A novel affinity ligands beta-D-glycopyranosylmethylamines derived from common D-aldohexoses linked to the carboxymethyl dextran layer of the SPR sensor surface served for interactions with a wide range of lectins. The method of preparation and use of the beta-D-mannopyranosyl glycosylated sensor surface was described. The results of affinity analysis of lectin-ligand interactions were evaluated and compared with data obtained from measurements using commercially available p-aminophenyl alpha-D-glycopyranosides. Possible applications and advantages of C- and O-glycosylated SPR biosensors are discussed.
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