Microbial control of growth, differentiation, metamorphosis and settlement of marine organisms.

微生物控制海洋生物的生长、分化、变态和定居。

基本信息

批准号：
63440015
负责人：
ISHIDA Yuzaburo
金额：
$ 17.28万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (A)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1991
项目状态：
已结题

项目摘要

In this study we attempted to make clear a mechanism of metamorphosis and settlement, and to search and isolate microalgae and bacteria participating in these phenomena, and to identify' their bioactive substances. The results obtained are as follows ;1. The endocine system ii of fundamental importance in controlling development and growth of fishes. Thyroid and pituitary glands differentiate during the final phase of yolk absorption in pelagic -egg species. Interrenal tissues appear later than both glands, around 2 weeks after hatching in Japanese flounder. Immumehistochemical techniques revealed production of GH and PRL prior to the time when the pituitary is histologically detectable. Tissue TH concentrations were at higher levels at fertilization, thereafter markedly reduced with embryonic development. They gradually increased with postlawal growth and development, and appreciably increased during metamorphosis in flatfishes. In some flatfishes, tissue concentration of cortisol als … More o exhibited a prominent surge, but the timing was significantly earlier than that of TH. These hormone level dynamics appeared to be intimately related to body structual, behavioral and ecological changes.2. Many marine microorganisms which stimulate settlement of flounder (Paralichthys obivaceus) larvae were surveyed. Marine Acinetobacter SS6-2 and Raphidophyta Chattonella antiqua a86 were effective on the settlement. The active substances were found in acetone or ethanol insoluble fraction.3. Dimethylsulfoniopropionate (DMSP) is the precursor of dimethylsulfide (DMS) which is the most abundant volatile sulfur compound in seawater. Various species of marine macroalgae (especially Rhodopohyta) and microalgae (especially Dinophyta and Haptophyta) contain DMSP. ' DMSP has promoting effect on growth, feeding and thrust power of several fishes. The biosynthetic pathway of DMSP from methionine in Crypthecodinium cohnii (Dinophyta). Methionine is first decarboxylated by methionine decarboxylase which requires pyridoxyal phsphate. We are now trying to purify this enzyme.4. Polyethyleneglycol method was applied to tranformation of the linearized plasmid pBI121 which contains the neomycin phosophotransferease II (NPTII) gene and beta-gluconidase (GUS) gene into the cell wall-less mutant of Chiamydomonas reinhardtii. This transformation procedure is very simple. Cells tranformed to kanamycin resistance were obtained. Southem blots of DNA from the transformant demonstrate the integration of the PNT II gene but GUS gene. We are now trying to make transgenic thalli of Ulva pertusa which can produce the growth hormone of tuna. Less

在这项研究中，我们试图清除这些现象，并识别其生物活性物质垂体在蛋黄的最后阶段都比在日本孵化后几周出现了肾脏间组织在某些扁平鱼类中，植物性的发育量增加了，更多的O表现出了明显的潮流，但一种时间与人体结构，行为和生态变化相关对幼虫的定居（paralichthys obivavaceus）在丙酮中有效。 dmsp对生长的影响促进了cohnii的生物合成途径（dinophyta）。 - chiamydomonas的突变体非常简单