Herbicidal antibiotic

Tab. 16.1 N ovel marker genes that avoid the use of potentially toxic antibiotics, herbicides and drugs for the selection of transgenic plants. ESR1, enhancer of shoot regeneration 1 CKI1, cyto-...

It has been established that DXS catalyzes the first step in a novel biosynthetic pathway leading to isoprenoids in bacteria, algae, plant chloroplasts, and in the malaria parasite, Plasmodium falciparum. DXS is therefore a novel target for antibiotics, herbicides, or anti-malarials. Our work has contributed to an understanding of the novel biosynthetic pathway and could further open new perspectives on how to inhibit the pathway in pathogenic bacteria, protists, or weeds. 

Cyclohexylamines Corrosion inhibitors, catalysts, antibiotics, herbicides, cycla-mate sweeteners in Asia... 

Combinatorial chemistry has become a powerful methodology for the construction of new compounds. Natural products, however, also have enormous potential as a source of new compounds. In particular, numerous useful microbial products have been isolated as antibiotics, herbicides, fungicides and enzyme-inhibitors. Moreover, microorganisms have provided various compounds with diverse bioactivities, such as immunomodulatory, antitumor and antihelmintical activities [1]. 

Methyl acetoacetate (MAA) and ethyl acetoacetate (EAA) are the most widely used esters they are found ia the pharmaceutical, agricultural, and allied industries. Both esters are used extensively as amine protecting agents ia the manufacture of antibiotics and synthetic sweeteners (Dane Salts) (147). Principal outiets for MAA are the manufacture of the organophosphoms insecticide dia2inon [33341-5] (148,149) and the uracil herbicides bromacil [31440-9] and terbacil [5902-51-2] (150,151) (see Insect conztiol technology Herbicides). 

Before the discovery of streptomycin, pyrazinamide (126) was one of the front runners in the treatment of tuberculosis. A broad spectrum of biological activity has been associated with pyrazine derivatives, ranging from the herbicidal activity of (127) to antibiotic activity... 

This is a large subject that can only be dealt with in the barest outline in the present text. Many antibacterial and antifungal compounds have been discovered in microorganisms, and some of them have been successfully developed as antibiotics for use in human and veterinary medicine. They lie outside the scope of this book. A considerable number of other microbial compounds act as insecticides, acaricides, or herbicides, although few of them have been developed commercially (Copping and Menu 2000, Copping and Duke 2007). 

DNA construct will often contain an effect gene and a selectable marker gene (such as antibiotic or herbicide resistance), both of which are bracketed by promoter and terminator sequences. A plasmid vector carries this cassette of genetic information into the plant genome by one of the above methods. 

Rationale. Microorganisms were isolated from soil and screened for toxin production according to the scheme in Figure 1. Some of the organisms causing strong inhibition on solid medium were tested for toxin production in liquid medium. Liquid culture will be required to obtain large amounts of material for commercial production of herbicides, however, the ability to produce toxins on solid medium does not necessarily imply toxin production in broth (34). Cyclo-heximide, a phytotoxic but relatively nonspecific antibiotic with little value as a herbicide, is produced by many actinomycetes. Liquid cultures were tested for cycloheximide to determine whether it caused the observed toxicity. 

The Shikimate pathway is responsible for biosynthesis of aromatic amino acids in bacteria, fungi and plants [28], and the absence of this pathway in mammals makes it an interesting target for designing novel antibiotics, fungicides and herbicides. After the production of chorismate the pathway branches and, via specific internal pathways, the chorismate intermediate is converted to the three aromatic amino acids, in addition to a number of other aromatic compounds [29], The enzyme chorismate mutase (CM) is a key enzyme responsible for the Claisen rearrangement of chorismate to prephenate (Scheme 1-1), the first step in the branch that ultimately leads to production of tyrosine and phenylalanine. 

Chemists have found numerous industrial applications for 1,2,3-thiadiazole derivatives. In particular, 1,2,3-thiadiazole derivatives have been used as insecticide synergists, herbicides, and polymer compounds. They have also been shown to have sedative, antibacterial, and antibiotic activity. Examples of these compounds were discussed in CHEC(1984) and CHEC-II(1996). 

Thiadiazoles have found applications as pharmaceuticals, fungicides, herbicides, bacteriocides, dyes, lubricant additives, and vulcanization accelerators. Cephalosporins incorporating a 1,2,4-thiadiazole ring into the side chain have good antibiotic and antimicrobial properties. 

Triazacyclononane derivatives, 24 56 Triazine-based antibiotics, 26 799 Triazine herbicides, 13 284, 321-322 Triazines, 18 769, 9 290-291 Triazines. See also, Environmental fate of triazines... 

Major chemical contaminants implicated in food safety include pesticides, herbicides, myeotoxins and antibiotics. These analytes have been targeted by numerous groups developing SPR biosensors. As these analytes are rather small (typical molecular weight < 1,000), inhibition assay has been a preferred detection format. Examples of chemical contaminants detected by SPR biosensors include pesticides atrazine and simazine (detection limits 0.05 ng/ml and 0.1 ng/ml respectively), mycotoxin Fumonisin B1 (detection limit 50 ng/ml ), and antibiotics Sulphamethazine, Sulphadiazine (detection limits 1 ng/ml and 20 ng/ml respectively). 

The beneficial effect of surfactants on enantioselective hydrogenations in water was exploited in the synthesis of a-aminophosphinic and a-aminophosphonic acids. These compounds are stmctural analogues of a-aminocarboxylic acids and their peptides find use as herbicides, bactericides and antibiotics [150,151]. With [Rh(BPPM)(COD)]Bp4 and similar catalysts fast ractions and e.e.-s up to 98% could be obtained in water in the presence of SDS (Scheme 3.12). 

The increased use of agricultural chemicals such as herbicides and animal antibiotics has been mirrored by an increased public concern regarding the impact of xenobiotic... 

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