Herbicide proteins

In thylakoid membranes (TM) diuron-type herbicides block electron flow between the primary and the secondary plastoquinone 1. Since, the binding site is located on the 32 Kd herbicide-binding protein (32 Kd H-B protein), which is embedded in both thylakoid monolayers 2, one can ask whether acyl lipids play a particular role in the herbicide-protein interaction, as suggested elsewhere 3. ... 

Those herbicides that block mitotic entry decrease or prevent the formation of mitotic figures in meristems. Amino acid, protein, RNA, DNA, and ATP synthesis and/or utilization can all attest cell growth (163,166). Although not registered as herbicides, cycloheximide [66-81-9] inhibits mitotic entry by inhibiting protein synthesis (167) hydroxyurea/727-(97-/7 inhibits DNA synthesis (168) and actinomycin D [50-76-0] nh2oix.s RNA synthesis (167). 

A method of detecting herbicides is proposed the photosynthetic herbicides act by binding to Photosystem II (PS II), a multiunit chlorophyll-protein complex which plays a vital role in photosynthesis. The inhibition of PS II causes a reduced photoinduced production of hydrogen peroxide, which can be measured by a chemiluminescence reaction with luminol and the enzyme horseradish peroxidase (HRP). The sensing device proposed combines the production and detection of hydrogen peroxide in a single flow assay by combining all the individual steps in a compact, portable device that utilises micro-fluidic components. 

The commercial exploitation of our increased understanding of protein stmcture will not, of course, be restricted to the pharmaceutical industry. The industrial use of enzymes in the chemical industry, the development of new and more specific pesticides and herbicides, the modification of enzymes in order to change the composition of plant oils and plant carbohydrates are all examples of other commercial developments that depend, in part, on understanding the structure of particular proteins at high resolution. 

One example of a naturally occurring diazirine, duazomycin A (137 Scheme 11.20), has been reported, isolated in 1985 from a Streptomyces species during a screen for herbicidal compounds [196], It was fotind to inhibit de novo starch synthesis and it was suggested that this is due to direct inhibition of protein synthesis. Duazomycin A is structurally related to 6-diazo-5-oxo-L-norleucine (138), also reported as a natural product from Streptomyces [197], which acts as a glutamine antagonist and inhibits purine biosynthesis [198],... 

The action of chlorine gas produces, for example, chloramine derivatives from herbicides, amino acids, peptides and proteins the active chlorine of these derivatives then... 

ESI performs well for the more polar compounds such as imidazolinone herbicides, sulfonylurea herbicides, triazine herbicides, phenoxy acid herbicides, and carbamate pesticides (to name a few). ESI also performs well with proteins and peptides. 

El-Sheekh, M.M., H.M. Kotkat, and O.H.E. Hammouda. 1994. Effect of atrazine herbicide on growth, photosynthesis, protein synthesis, and fatty acid composition in the unicellular green alga Chlorella kessleri. Ecotoxicol. Environ. Safety 29 349-358. 

All-a-proteins, 20 826-827 All-fi-proteins, 20 827-828 Alleles, floxed, 72 461 Allelochemicals, as herbicide leads, 73 355-357... 

The herbicide alachlor (4.146, Fig. 4.7) also displayed species-dependent toxicity, since it induced nasal tumors in rats but not in mice. Its metabolic scheme in rats and mice (Fig. 4.7) shows that alachlor can be transformed into 2,6-diethylaniline (4.149) by two different pathways, one of which proceeds via formation of 4.147. The other pathway implies glutathione (GSH) conjugation, followed by /3-lyase-mediated liberation of the thiol, followed by S-methylation to produce the methylsulfide 4.148. The two secondary amides 4.147 and 4.148 were hydrolyzed by microsomal arylamidases, but alachlor itself was not a substrate for this enzyme. The hydrolytic product 2,6-diethylaniline (4.149) was oxidized in nasal tissues to the electrophilic quinonimine metabolite 4.150, which can bind covalently to proteins. Aryl-... 

Krause, A.A. and Niemczyk, H.D. Gas-liquid chromatographic analysis of chlorthal-dimethyl herbicide and its degradates in turfgrass thatch and soil using a solid-phase extraction technique, J. Environ. Sci Health, B25(5) 587-606, 1990. Kresheck, G.C., Schneider, H., and Scheraga, H.A. The effect of DzO on the thermal stability of proteins. Thermod3mamic parameters for the transfer of model compounds from HzO to DzO, J. Phys. Chem., 69(9) 3132-3144, 1965. 

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