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High throughput synthesis and screening: the partner of genomics for discovery of new chemicals for agriculture

Published online by Cambridge University Press:  20 January 2017

F. Dan Hess
Affiliation:
AffyAgro Unit of Affymax Research Institute, 3410 Central Expressway, Santa Clara, CA 95051; [email protected]
Richard J. Anderson
Affiliation:
AffyAgro Unit of Affymax Research Institute, 3410 Central Expressway, Santa Clara, CA 95051; [email protected]
Jeff D. Reagan
Affiliation:
AffyAgro Unit of Affymax Research Institute, 3410 Central Expressway, Santa Clara, CA 95051; [email protected]

Abstract

As new targets for herbicide action are identified from genomics research, large and diverse chemical collections and high-throughput assays will be required to maximize the probability of identifying compounds with activity at these targets. The new technology of combinatorial synthesis and high-throughput, miniaturized, in vitro screening, which has become an integral part of pharmaceutical discovery, is now being applied to discover new herbicides, insecticides, and fungicides. Depending on the synthesis design, the products of a combinatorial synthesis, referred to as a library, may be either unbiased or biased toward an intended target. Unbiased libraries are generally prepared to maximize chemical diversity around a central core structure or scaffold. Often containing 10,000 to 30,000 compounds each, these libraries are encoded and prepared by a combinatorial methodology known as mix-and-split, which produces compounds as mixtures. The preparation of these large libraries requires robust synthetic methodology that will accommodate reactants (building blocks) with diverse structures. Biased libraries tend to be smaller in size, ranging from 100 to 2,500 compounds. They are prepared using synthetic methodology that produces collections of discrete compounds (parallel synthesis) or pools of five to 10 compounds per pool (mix-and-split synthesis). Compounds in biased libraries are rationally designed to contain structural motifs or pharmacophores that are presumed to be beneficial for activity on the intended target. Screening is conducted in microtiter assay plates containing from 96 to 864 wells per plate. For in vitro assays, high-density formats (864 wells per plate) are preferred. The higher density format allows for testing higher concentrations and fewer compounds per well, which leads to a more rapid identification of the active molecules. For in vivo assays, 96-well formats are preferred. Regardless of the microtiter plate format, multiple beads are distributed into plates by robotic pipetting, and single beads are distributed via robot-controlled suction pipets. Test compounds are cleaved from the beads and transferred in solvent to assay plates. Required reagents are added to the plate to initiate the assay. A wide range of in vitro and in vivo herbicide, insecticide, and fungicide assays can be conducted in microtiter plates.

Type
Symposium
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Balkenhohl, F., von dem Bussche-Huennefeld, C., Lansky, A., and Zechel, C. 1996. Combinatorial synthesis of small organic molecules. Angew. Chem. Int. Ed. Engl. 35:22882337.CrossRefGoogle Scholar
Bronstein, I., Olesen, C.E.M., Martin, C. S., Schneider, G., Edwards, B., Sparks, A., and Voyta, J. C. 1994. Chemiluminescent detection of DNA and protein with CDP and CDP-Star 1,2-dioxetane enzyme substrates. Pages 269272 In Campbell, A. K., Kricka, L. J., and Stanley, P. E., eds. Bioluminescence and Chemiluminescence: Fundamentals and Applied Aspects. Chichester, England: Wiley.Google Scholar
Cook, N. D. 1996. Scintillation proximity assay: a versatile high-throughput screening technology. Drug Disc. Today 1:287294.Google Scholar
Ellman, J. A. 1996. Design, synthesis, and evaluation of small-molecule libraries. Acc. Chem. Res. 29:132143.Google Scholar
Fitch, W. L., Baer, T. A., Chen, W., et al. 1999. Improved methods for encoding and decoding dialkylamine-encoded combinatorial libraries. J. Comb. Chem. 1:188194.Google Scholar
Fitch, W. L., Szardenings, A. K., and Fujinari, E. M. 1997. Chemiluminescent nitrogen detection for HPLC: an important new tool in organic analytical chemistry. Tetrahedron Lett. 38:16891692.Google Scholar
Gordon, E. M., Barrett, R. W., Dower, W. J., Fodor, S.P.A., and Gallop, M. A. 1994. Applications of combinatorial technologies to drug discovery. 2. Combinatorial organic synthesis, library screening strategies, and future directions. J. Med. Chem. 37:13851401.Google ScholarPubMed
Gordon, E. M., Gallop, M. A., and Patel, D. V. 1996. Strategy and tactics in combinatorial organic synthesis. Applications to drug discovery. Acc. Chem. Res. 29:144154.Google Scholar
Hemmila, I. and Webb, S. 1997. Time-resolved fluorometry: an overview of the labels and core technologies for drug screening applications. Drug Disc. Today 2:373381.CrossRefGoogle Scholar
Johnson, P. C., Ware, A., Cliveden, P. B., Smith, M., Dvorak, A. M., and Salzman, E. W. 1985. Measurement of ionized calcium in blood platelets with the photoprotein aequorin. J. Biol. Chem. 260:20692076.Google Scholar
McGregor, M. J. and Muskal, S. M. 1999. Pharmacophore fingerprinting. 1. Application to QSAR and focused libraries. J. Chem. Inf. Comput. Sci. 39:569574.CrossRefGoogle ScholarPubMed
McGregor, M. J., and Muskal, S. M. 2000. Pharmacophore fingerprinting. 2. Application to primary library design. J. Chem. Inf. Comput. Sci. 40:117125.CrossRefGoogle ScholarPubMed
Murashige, T. and Skoog, F. 1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Plant Physiol. 15:473497.Google Scholar
Pauch, M. H., Price, L. A., Kajkowski, E. M., Strnad, J., Dela Cruz, F., Heinrich, J., Ozenberger, B. A., and Hadcock, J. R. 1998. Heterologous G-protein coupled receptors in Saccharomyces cerevisiae: methods for genetic analysis and ligand identification. Pages 196212 In Lynch, K. R., ed. Identification and Expression of G-Protein Coupled Receptors. New York: Wiley-Liss.Google Scholar
Silen, J. L., Lu, A. T., Solas, D. W., et al. 1998. Screening for novel antimicrobials from encoded combinatorial libraries by using a two-dimensional agar format. Antimicrob. Agents Chemother. 42:14471453.Google Scholar
Stables, J., Scott, S., Brown, S., Roelant, C., Burns, D., Lee, M. G., and Rees, S. 1999. Development of a dual glow-signal firefly and Renilla luciferase assay reagent for the analysis of G-protein coupled receptor signalling. J. Recept. Signal Transduct. 19:395410.Google Scholar