古狗BT的結果: Bt protein; also Bt toxin

Bt protein; also Bt toxin

 A protein that is toxic to chewing insects and is produced by the soil bacterium Bacillus thuringiensis and has long been used as a biological pesticide.

By means of genetic engineering, the genes for Bt toxin can be isolated from Bacillus thuringiensis and transferred to plants. The plant is thus conferred the ability to produce the insect toxin on its own.

There are different forms of Bt toxin that are specifically active against certain groups of insects. About 170 naturally occuring Bt toxins with varying specificities are known. 

For genetically engineered insect resistance, different variants of Bt genes are transferred, e.g. Cry 1Ab, Cry 1Ac and Cry 9c for maize. They differ both in terms of their length and in terms of the promoters used. The transgenic maize varieties differ depending on the Bt gene variant used, both in terms of the amount of Bt protein they produce and its distribution within the plant. Some Bt maize varieties produce the Bt protein primarily in the stem, while other produce it in all plant parts. 

 

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What are Bt proteins?

Bt stands for the naturally occurring bacterium Bacillus thuringiensis. Bt lives in the soil and is found all over the world. Some types of Bt produce a protein crystal that is toxic to insects. These protein crystals have been used in organic farming for over 50 years to control insects. The genes producing these proteins are now engineered so that plants can make the protein in their cells.

 

 

所有跟帖： 

• 是的。這裏有個量的問題。事實上出現過不少使用bt不當而導致中毒的事件。但是至少外用的時候 -woth- ♀ (27 bytes) () 08/05/2011 postreply 14:01:13

• 打個比方說，我們把bt殺蟲劑作為外用農藥的時候，肯定有打藥時間，打藥濃度等不同規範 -woth- ♀ (133 bytes) () 08/05/2011 postreply 14:13:14

• 好問題！那就比較一下外用和內用 -TBz- ♂ (1653 bytes) () 08/05/2011 postreply 17:06:46

• 那就來分析一下： -woth- ♀ (2244 bytes) () 08/05/2011 postreply 18:05:55

• 結論：此BT非彼BT -TBz- ♂ (151 bytes) () 08/05/2011 postreply 21:44:03

• 有bt作為生物農藥使用不當而導致中毒的事件嗎？ -viewfinder- ♀ (98 bytes) () 08/05/2011 postreply 22:37:35

• 一個可參考的例子： -viewfinder- ♀ (74 bytes) () 08/05/2011 postreply 22:40:58

• 剛查了一下，不好意思，俺記錯了。不是bt殺蟲劑的中毒事件，是其他的。 -woth- ♀ (0 bytes) () 08/06/2011 postreply 19:02:37

• 這個王月丹連蘇雲金杆菌與致病菌蠟樣芽孢杆菌都不會區分，你還能指望他什麽？ -加州老李- ♀ (1662 bytes) () 08/05/2011 postreply 14:04:04

• 受不了你了，這就是你的支持轉基因食品的方式麽？ -woth- ♀ (0 bytes) () 08/05/2011 postreply 14:07:43