Delivery methods for peptide and protein toxins in insect control.

Since the introduction of DDT in the 1940s, arthropod pest control has relied heavily upon chemical insecticides. However, the development of insect resistance, an increased awareness of the real and perceived environmental and health impacts of these chemicals, and the need for systems with a smaller environmental footprint has stimulated the search for new insecticidal compounds, novel molecular targets, and alternative control methods. In recent decades a variety of biocontrol methods employing peptidic or proteinaceous insect-specific toxins derived from microbes, plants and animals have been examined in the laboratory and field with varying results.

Structural studies of a potent insect maturation inhibitor bound to the juvenile hormone esterase of Manduca sexta.

Juvenile hormone (JH) is an insect hormone containing an alpha,beta-unsaturated ester consisting of a small alcohol and long, hydrophobic acid. JH degradation is required for proper insect development. One pathway of this degradation is through juvenile hormone esterase (JHE), which cleaves the JH ester bond to produce methanol and JH acid.

Method to site-specifically identify and quantitate carbonyl end products of protein oxidation using oxidation-dependent element coded affinity tags (O-ECAT) and nanoliquid chromatography Fourier transform mass spectrometry.

Protein oxidation is linked to cellular stress, aging, and disease. Protein oxidations that result in reactive species are of particular interest, since these reactive oxidation products may react with other proteins or biomolecules in an unmediated and irreversible fashion, providing a potential marker for a variety of disease mechanisms. We have developed a novel system to identify and quantitate, relative to other states, the sites of oxidation on a given protein.

Irreversibly binding anti-metal chelate antibodies: Artificial receptors for pretargeting.

Antibodies against metal chelates may potentially be used in biomedical applications such as targeted imaging and therapy of cancer. Highly specific monoclonal antibodies can be developed, but their binding strength needs to be maximized for them to be of practical use. In general, the half-life for dissociation of an antibody-ligand complex is more than an order of magnitude lower than the half-lifetimes for decay of medically useful radiometal ions.

Irreversible engineering of the multielement-binding antibody 2D12.5 and its complementary ligands.

Engineering the permanent formation of a receptor-ligand complex has a number of potential applications in chemistry and biology, including targeted medical imaging and therapy. Starting from the crystal structure of the rare-earth-DOTA binding antibody 2D12.5 (Corneillie, T.

Converting weak binders into infinite binders.

Monoclonal antibody 2D12.5 binds DOTA chelates of all the rare earths with K(d) approximately 10(-)(8) M, making it useful for the capture of probe molecules with a variety of properties. To make 2D12.

Evaluation of cleavable (Tyr3)-octreotate derivatives for longer intracellular probe residence.

Radioligand targeting of somatostatin receptor subtype 2 (sstr2)-positive tumors with synthetic somatostatin analogues such as octreotide is subject to improvement in tumor to nontumor biodistribution, in part because internalization of such somatostatin analogues is limited by sstr2 recycling to the cell surface. We reasoned that it might be possible to prepare probe-carrying somatostatin analogues that would escape recycling, efficiently depositing probe molecules inside cells and ultimately increasing their intracellular concentration. We have incorporated cathepsin-B-cleavable linkers into (Tyr3)-octreotate chelate conjugates and examined these constructs as to cellular uptake, externalization, subcellular localization, and cleavage in the rat pancreatic tumor cell line AR42J in culture.

Element-coded affinity tags for peptides and proteins.

Isotope-coded affinity tags (ICAT) represent an important new tool for the analysis of complex mixtures of proteins in living systems [Aebersold, R., and Mann, M. (2003) Nature, 422, 198-207].

Molecular tools for targeted imaging and therapy of cancer.

Here we review an approach to the design and production of antibody/ligand pairs for use in cell targeting procedures, to achieve functional affinity far greater than avidin/biotin. Using fundamental chemical principles, we have developed antibody/ligand pairs that retain the binding specificity of the antibody, but do not dissociate. By eliminating the dissociation of the ligand from the antibody, we have made the affinity functionally infinite.

A rare earth-DOTA-binding antibody: probe properties and binding affinity across the lanthanide series.

An antibody that binds rare earth complexes selectively could be used as a docking station for a set of probe molecules, of particular interest for medical imaging and therapy. The rare earths are rich in probe properties, such as the paramagnetism of Gd, the luminescence of Tb and Eu, and the nuclear properties of Lu and Y. We find that antibody 2D12.