Copper-treated soybean ( Glycine max ) seedling shows significant inhibition in soybean root growth, and enhancement in POD activity. Cu is an efficient catalyst in the formation of several reactive oxygen species and free radical. The increase in POD activity induced by Cu might remove excess hydrogen peroxide serving a detoxifying role during Cu-treatment. The increase of cationic ( pI 8.9, pI 8.3 and pI 7.7 ) PODs and anionic ( pI 6.5, pI 5.6 and pI 4.4 ) PODs activities is accompanied by a rise of lignin contents in Cu-treated tissues. We suggest that the increase in cationic ( pI 8.9, pI 8.3 and pI 7.7 ) and anionic ( pI 6.5, pI 5.6 and pI 4.4 ) PODs induced by Cu is responsible for lignin synthesis in soybean roots during Cu treatment.

Abstract The significant root growth inhibition in zinc-treated soybean (Glycine max) seedling correlated with the increase of PODs and laccases activity. The increase of the activities of PODs (pI 8.3, pI 7.7, pI 4.8, pI 4.4 and pI 3.7) and laccases (pI 9.4, pI 8.3, pI 7.4, and pI 3.7) are accompanied by a rise of lignin contents in Zn-treated tissues. Our results suggested that laccases work during the early stage of Zn treatment. Laccases and peroxidases work cooperatively in lignin synthesis when the time of Zn treatment was prolonged.

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Aluminum-treated rice seeding (Oryza sativa L. cv. Taichung Native 1 and O. sativa L. cv. Tainung 67) showed significant inhibition in rice root growth, and an enhancement of POX activity. In Tainung 67 cultivar rice synthesizes more lignin in Al-treated tissue. Meanwhile, the decrease of H2O2 levels is accompanied with the enhancement of POX activity in Al-treated tissue. The increase in POX activity induced by Al might remove excess hydrogen peroxide serving a detoxifying role and synthesizing more lignin for protection. In Taichung native 1 cultivar, high amounts of H2O2 accumulated in Al-treated tissues could be due to the less amounts of POX induced by Al. In response to Al treatment, the Taichung native 1 cultivar synthesizes less lignin in comparison with that of Tainung 67, and is more Al-less tolerant. Therefore, the Tainung 67 cultivar is more tolerant to Al than Taichung native 1.

The plant peroxidases (EC1.11.17) exit as a large family of isozymes. These isozymes have more than 50% amino acid sequence differences. The function of Wasaba japonica peroxides plays the role as IAA oxidases. The kinetics result shows Wasabia japonica peroxidases displayed affinity (Km = 17.1 £gM) for IAA. The kinetics results in Wasabia japonica peroxidases display affinity (Km = 80.6 £gM) for syringaldazine. LC/MS/MS technique described the data that has proven to be a method for identification and characterization of proteins. The soluble proteins extracted form Wasabia japonica was purified by gel filtration chromatography and two-dimensional gel electrophoresis (2-DE). LC-MS/MS analyses of 2-DE gel spots and identify proteins structure based on the protein fragmentation characteristics. The Mascot Search Results showed that Wasabia japonica peroxidase has a significant similarity (10%) with Arabidopsis thaliana peroxidase.

The auxins, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and naphthaleneacetic acid (NAA), promotes the formation of adventitious root in hypocotyls of soybean (Glycine max). IBA significantly promotes the formation of adventitious roots more than IAA and NAA . The activity of anionic pI 3.7 peroxidase (POX) and cationic pI 8.5 POX were inhibited by exogenous auxins during the induction of adventitious root on day 2. Besides, the activity of pI 5.3 POX was enhanced by IBA during the initiation stage on day 4. The increase of the activity of pI 5.3 POX was accompanied by the increase of H2O2 levels. In the previous researches, it shows that the promoter of pI 8.5 POX gene contains both ARF/AuxRE and CATATGGMSAUR motifs that are responded to auxins. In this studies, the pI 5.3 POX gene, which responses to auxins a day or two later, contains only ARF/AuxRE motif. The regulation of pI 5.3 POX gene is probably initiation phase-dependent. The results suggest that anionic pI 5.3 POX produces significant amount of H2O2 through the binding of auxin to POX and mediate the auxin signaling pathway leading to plant growth .

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 156-165). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Leaves vi, ix and 167 are blank. Typescript. Includes bibliographical references (leaves 173-174). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Leaves vi, ix and 167 are blank. Typescript. Includes bibliographical references (leaves 173-174). Also available on the Internet.

Thesis (M. Phil.)--University of Hong Kong, 1982.