碩士 / 國立臺灣海洋大學 / 水產養殖學系 / 93 / Abstract
The present thesis investigated the effects of pathogenic Vibrio harveyi on blood coagulating mechanism and hemocyanin of white shrimp Litopenaeus vannamei.
The unclottable hemolymph of shrimps affected by the injection of bacterial cells or extracellular products ( ECP ) of V. harveyi could be re-clottable by the addition of 0.2 U/ml transglutaminase and 4mM CaCl2 ( clotting factors ). This phenomenon could be found by visualizing the occurrence of larger coagulogen arc on the Crossed Immunoelectropho- resis ( CIE ) gels. In addition, the degraded coagulogen -smaller molecular- weight ( MW ) component, could be recovered to 200 kDa as visualized on SDS-PAGE in general. However, the degraded coagulogen even could be recovered to 400 kDa in some hemolymph obtained from shrimp treated with bacterial cells.
The hemolymph of white shrimp was found unclottable after injecting bacterial cells or ECP into the respective shrimps. The 400 kDa ( high MW ) coagulogen was found degraded to smaller MW component as visualized on the CIE gels or determined by ELISA assay. In addition, the reduction of hemocyanin could also be visualized on the CIE gels or determined by ELISA assay.
The changes of genetic expression ( mRNA ) of the coagulogen, transglutaminase and hemocyanin in the hepato- pancreas of while shrimp affected by bacterial cells and ECP of V. harveyi were also investigated by using Absolute Real-Time Quantitation PCR. The results revealed that the mRNA expression of both coagulogen and transglutaminase was enhanced while the mRNA expression of hemocyanin was reduced post bacterial or ECP challenge .
The results of present study reveal that the hemolymph coagulogen of white shrimp is reduced in amount and degraded to smaller MW components, leading to the occurrence of unclottable hemolymph when infected by V. harveyi. The enhanced mRNA expression of coagulogen and transglutaminase in the shrimp hepatopancreas may be regulated by the animal to compensate the destruction of these two important clotting factors during the infection of V. harveyi. In addition, the destruction of hemocyanin of the shrimp infected by V. harveyi may be more serious since its quantitative reduction not only occurred in the hemolymph in terms of protein but also in the hepatopancreas in terms of mRNA expression. Therefore, except the destruction of coagulating mechanism, the destruction of respiratory reaction ( hemocyanin reduction ) may well be another effect caused by V. harveyi leading to the lethality during the disease process in the white shrimp.
| Identifer | oai:union.ndltd.org:TW/093NTOU5086033 |
| Date | January 2005 |
| Creators | Yu-Chen Wu, 吳育甄 |
| Contributors | Kuo-Kau Lee, 李國誥 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 107 |
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