Insecticidal activity fragments

Putative a4 and /or aS helices may be involved in determining the insecticidal activity. Putative a6 helix may be involved in the association of the 20-kDa and 45-kDa fragments. 

Figure 6. Insecticidal activity of the fusion proteins of the CryllA fragments. The Cry4A fusion proteins were adsorbed to the latex beads, and given to the larvae of C. pipiens to give a final concentration of 0.5 mg/mL...

Figure 10. The insecticidal activity of the fusion proteins of the Cryl 1A processed fragments. GSTIIA K, GSTI IA-36k ...

The replacement of the 3-phenoxybenzyl alcohol fragment by 2-methyl[1,1 -biphenyl]-3-yl leads to an increase in initial and residual foliar activity in the alkyl aryl oxime ethers. An unanticipated result was the activity of these oxime ethers as soil insecticides. The corresponding 3-phenoxybenzyl alcohol oxime ethers were inactive as soil insecticides. The results of a structure activity relationship study revealed biological activity is enhanced by electron withdrawing substituents. 

On the basis of insecticidal spectrum and size of the toxic polypeptide fragment, we presently defined 3 types of lepidopteran-active B.t. toxins. 

Structural modifications of 4 regarding the substitution pattern of the TFM moiety, modification of nitrogen substituents or variation of the pharmacophore have indicate that this results in drastic changes in insecticidal potency [65] and that the incorporation of structural fragments known from previous neonicoti-noid insecticides does not necessarily lead to compounds retaining higher activity. 

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