| 1. |
- Masarova, Jana, et al.
(författare)
-
Mannan-penicillin G acylase neoglycoproteins and their potential applications in biotechnology
- 2004
-
Ingår i: Biotechnology and Applied Biochemistry. - 1470-8744. ; 39:3, s. 285-291
-
Tidskriftsartikel (refereegranskat)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.
|
|
| 2. |
- Mecklenburg, M., et al.
(författare)
-
Differentiation of human serum samples by surface plasmon resonance monitoring of the integral glycoprotein interaction with a lectin panel
- 2002
-
Ingår i: Analytica Chimica Acta. - 0003-2670 .- 1873-4324. ; 459:1, s. 25-31
-
Tidskriftsartikel (refereegranskat)abstract
- Bacterial infection and inflammation result in massive changes in serum glycoproteins. These changes were investigated by the interaction of the saccharide glycoprotein moiety with lectins. A panel of eight lectins (Canavalia ensiformis, Bandeiraea simplicifolia BS-I, Arachis hypogaea, Phytolacca americana, Phaseolus vulgaris, Artocarpus integrifolia, Triticum vulgaris and Pisum sativum) was used to differentiate human serum glycoproteins obtained from patients with various bacterial infections. Lectin functionalised sensing layers were created on gold-coated wafers and lectin-glycoprotein interactions were monitored by surface plasmon resonance. The interaction of the lectin panel with serum glycoproteins produces unique patterns. Principal component analysis (PCA) was used to analyse the patterns. The actual panel of eight lectins enabled discrimination between sera obtained from patients sick with bacterial infection and healthy patients. Extended lectin panels have the potential to distinguish between types of bacterial infection and identify specific disease state. © 2002 Elsevier Science B.V. All rights reserved.
|
|
| 3. |
- Mislovicova, D, et al.
(författare)
-
Influence of mannan epitopes in glycoproteins - Concanavalin A interaction. Comparison of natural and synthetic glycosylated proteins
- 2002
-
Ingår i: International Journal of Biological Macromolecules. - 1879-0003. ; 30:5, s. 251-258
-
Tidskriftsartikel (refereegranskat)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.
|
|
| 4. |
- Mislovicova, D, et al.
(författare)
-
Neoglycoconjugates of mannan with bovine serum albumin and their interaction with lectin concanavalin A
- 2002
-
Ingår i: Bioconjugate Chemistry. - : American Chemical Society (ACS). - 1520-4812 .- 1043-1802. ; 13:1, s. 136-142
-
Tidskriftsartikel (refereegranskat)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.
|
|
| 5. |
|
|
| 6. |
- Nahálková, Jarmila, et al.
(författare)
-
Affinity analysis of lectin interaction with immobilized C- and O-gylcosides studied by surface plasmon resonance assay
- 2002
-
Ingår i: Journal of Biochemical and Biophysical Methods. - 0165-022X .- 1872-857X. ; 52:1, s. 11-18
-
Tidskriftsartikel (refereegranskat)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.
|
|
| 7. |
- Ramanathan, Kumaran, et al.
(författare)
-
Gold-coated capillary based 2,4-dichlorophenoxyacetic acid chemi-lumincscent assays: possibilities towards multianalysis
- 2002
-
Ingår i: Biosensors and Bioelectronics. - 0956-5663. ; 17:4, s. 283-288
-
Konferensbidrag (refereegranskat)abstract
- The application of gold-coated glass capillaries for the design of a sensitive chemiluminescent immunoassay for 2,4-dichlorophenoxyacetic acid (2,4-D) is reported. The gold coating on the glass capillaries has been partially characterized and its effect on enhancing the signal intensity has been measured. A simple photo-multiplier tube-based photon detector is used for this purpose. At least three times improvement in the signal intensity is observed compared to uncoated glass capillaries, with a consequent improvement in the sensitivity of detection. Using such gold-coated glass capillaries, 2,4-D in the range 10(-9) to 10(-13) mol/l is detectable at a precision of +/-15% (CV%) and a limit of detection of 10(-15) mol/l is achievable. The possibility of using such gold-coated capillaries with a portable multianalytical set-up for field studies is also demonstrated.
|
|
