TY  - GEN
A1  - Oliveira Jr, E. N.
A1  - Gueddari, Nour E. El
A1  - Moerschbacher, Bruno M.
A1  - Peter, Martin
A1  - Franco, Telma
T1  - Growth of phytopathogenic fungi in the presence of partially acetylated chitooligosaccharides
N2  - Four phytopathogenic fungi were cultivated up to six days in media containing chitooligosaccharide mixtures differing in average DP and FA. The three different mixtures were named Q3 (which contained oligosaccharides ofDP2–DP10, withDP2–DP7 asmain components), Q2 (which contained oligosaccharides of DP2–DP12, with DP2–DP10 as main components) and Q1 (which derived from Q2 and contained oligomers of DP5–DP8 with hexamer and a heptamer as the main components). The novel aspect of this work is the description of the effect of mixtures of oligosaccharides with different and known composition on fungal growth rates. The growth rate of Alternaria alternata and Rhizopus stolonifer was initially inhibited by Q3 and Q2 at higher concentrations. Q1 had a growth stimulating effect on these two fungi. Growth of Botrytis cinerea was inhibited by Q3 and Q2, while Q1 had no effect on the growth of this fungus. Growth of Penicillium expansum was only slightly inhibited by higher concentrations of sample Q3, while Q2 and Q1 had no effect. The inhibition of growth rates or their resistance toward chitooligosaccharides correlated with the absence or presence of chitinolytic enzymes in the culture media, respectively.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 105 
KW  - Chitosan
KW  - Chitinase
KW  - Fungi
KW  - Oligosaccharides
KW  - Phytopathogens
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-42646
ER  - 
TY  - THES
A1  - Bahrke, Sven
T1  - Mass spectrometric analysis of chitooligosaccharides and their interaction with proteins
T1  - Massenspektrometrische Analyse von Chitooligosacchariden und ihre Wechselwirkungen mit Proteinen
N2  - Chitooligosaccharides are composed of glycosamin and N-acetylglycisamin residues. Gel permeations chromatography is employed for the separation of oligomers, cation exchange chromatography is used for the separation of homologes and isomers. Trideuterioacetylation of the chitooligosaccharides followed by MALDI-TOF mass spectrometry allowes for the quantitation of mixtures of homologes. vMALDI LTQ multiple-stage MS is employed for quantitative sequencing of complex mixtures of heterochitooligosaccharides. Pure homologes and isomers are applied to biological assays. Chitooligosaccahrides form high-affinity non-covalent complexes with HC gp-39 (human cartilage glycoprotein of 39 kDa). The affinity of the chitooligosaccharides depends on DP, FA and the sequence of glycosamin and N-acetylglycosamin moieties. (+)nanoESI Q TOF MS/MS is used for identification of a high-affinity binding chitooligosaccharide of a non-covalent chitinase B - chitooligosaccharide complex. DADAA is identified as the heterochitoisomer binding with highest affinity and biostability to HC gp-39. Fluorescence based enzyme assays confirm the results.
N2  - Chitooligosaccharide sind aus Glycosamin und N-Acetylglycosamun aufgebaut. Gelpermeationschromatographie wird für die Trennung von Oligomeren verwendet, die Kationenaustauschchromatographie wird zur Trennung von homologen- und Isomerengemischen angewendet. Trideuterioacetylierung der Chitooligosaccharide gefolgt von einer Analyse mittels MALDI-TOF MS erlaubt die quantitative Analyse von Homologengemischen. vMALDI LTQ multiple-stage MS wird angewendet zur Sequenzanalyse und Quantifizierung komplexer Gemische von Heterochitooligosacchariden. Reine Homologe und Isomere werden für biologische Assays verwendet. Dabei zeigt sich, dass Chitooligosaccharide mit HC gp-39 hochaffine Komplexe bilden. Die Affinität der Chitooligosaccharide hängt vom DP, FA und der Sequenz der Chitooligosaccharide ab. (+)nanoESI Q TOF MS/MS wird erfolgreich angewendet zur Identifizierung eines Chitooligosaccharides, das mit hoher Affinität an Chitinase B (Serratia marcescens) bindet. DADAA wurde als die Sequenz des Isomers identifiziert, das mit höchster Affinität und Biostabilität an aktive Chitinase B bindet. Fluoreszenz basierte Enzymassays konnten dieses Ergebnis bestätigen.
KW  - Chitooligosaccharide
KW  - HPLC
KW  - Massenspektrometrie
KW  - Chitolektine
KW  - Chitinase
KW  - Chitooligosaccharides
KW  - HPLC
KW  - Mass Spectrometry
KW  - Chitolectins
KW  - Chitinase
Y1  - 2008
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-20179
ER  -