Dissertation > Excellent graduate degree dissertation topics show

Comparison of Ca～(2+) Location in the Plant Mature Cell Walls and Flammulina Velutipes Stipe

Author: ZhuZuo
Tutor: YuanSheng
School: Nanjing Normal University
Course: Microorganism
Keywords: Cucumber etiolated seedlings Flammulina Cell wall Ca2 positioning
CLC: S646.15
Type: Master's thesis
Year: 2007
Downloads: 115
Quote: 0
Read: Download Dissertation

Abstract

Extracted in the laboratory from Aspergillus pectinase successful recovery of higher plants mature cell wall expansion, and speculated that pectin may result in higher plants cell wall hardening component. Dr. Zhao Qingxin niger pectinase purified and recombinant expression of the endo-pectinase three able to recover the higher plants mature walls expansionary PG A pelA, Pel1 further proof pectinase capable of acting on cucumbers and other dicotyledons mature cell wall, to restore the sensitivity of the cell wall expansion protein, thereby restoring the mature cell wall expansion. Proteases, only of xylose and arabinoxylan hydrolysis Xyn III protein and the xyloglucan, mixed key glucan substrates Cel12A protein was confirmed to have not the recovery expansion of the cucumber and other dicotyledonous plants mature walls . These phenomena implied cellulose, hemicellulose, xyloglucan mixed key glucan and structural proteins may not be the key factor in the plant cell wall hardening, let us turn our gaze to the interaction between the pectin molecules research. The pectin possible only with cucumber dicotyledonous plant cell wall hardening directly related to cell wall components in the plant cell wall maturation process, the pectin is how to affect the plant cell wall hardening and expansionary worth our study. Acidic pectin bridge bond is formed, resulting in the formation of the calcium pectinate improve the hardness of the pectin and calcium ions was found in previous studies. A lot of calcium bridge formation can significantly increase the hardness of the cell wall, while in the mature cell wall has a more acidic pectin, so we need to know whether the calcium ions in the cell wall also has a distribution of more mature walls, it is possible and acidic Pectin formed a lot of calcium bridge, resulting in the hardening of the cell wall. This article by Ca ^{2 potassium pyroantimonate Histochemical Localization of law, cucumber etiolated seedlings hypocotyl the partition segment serial sections calcium positioning. Found that the density of calcium ions in the cell wall of progressively increasing from the top to the base, in the presence of a large number of calcium ions in the mature cell wall, the bridge there are a lot of mature cell wall calcium. Further the Ca ^{2 obligate the chelator EGTA preprocessing instead pectinase restore the mature cell wall expansion, calcium bridge is a key factor in cell wall hardening. That Aspergillus pectinase through interrupted calcium Bridge Recovery mature cell wall expansion. Aspergillus pectinase restore the mature cell wall expansion mechanism provides a solid theoretical foundation. In order to further study the mature cell wall expansion of the mechanism of Aspergillus pectinase recovery, after the gene sequence alignment by RT-PCR from tomato fruit with the highest degree of similarity of Aspergillus pectinase PGA cDNA sequence and prokaryotic expression and PG auxotrophic yeast eukaryotic expression were obtained by the high level of expression of the inclusion body protein and low expression amount of the supernatant protein, protein finally obtained is only a very weak activity can not be the further recovery elongation dynamic determination, but this entry experiment is still further research Aspergillus pectinase recovery the mature walls expansionary mechanism provides a wealth of experimental data. Flammulina both medicinal value and food value of higher fungi, its rapid growth similar plant elongation growth will also occur in the fruiting body growth stage. Although so far, the Flammulina cell wall extension mechanism is still not known. Professor Yuan Sheng found cell wall Ca2 participate in the fungal cell wall physical modification of direct evidence, provided the experimental basis for our research of Agarics cell wall. May be related to the role of acidic calcium polysaccharide widely found in the fact that in the cell walls of higher fungi provide arguments for our research. In order to better use of Agaricales resources, to study the mechanism of Agaricales cell wall extension paper Ca ^{2 potassium pyroantimonate Histochemical Localization applied to the analysis of large fungal cell wall calcium found the Flammulina stipe calcium ion density increased down from the growth center, longer stipe down the middle of calcium ions is significantly reduced. Observed that there are a lot of calcium in in across the Macrofungi hole. Confirmed that the calcium ion to participate in large-scale the Agaricales cell wall modification, provided the experimental basis for further study of the mechanism of the expansion.}}}

Related Dissertations

CLC: > Agricultural Sciences > Gardening > Vegetable gardening > Fungi ( mushroom ) > Fold Agarics > Flammulina (gross handle money bacteria)
© 2012 www.DissertationTopic.Net Mobile