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The major vault protein (MVP) mediates diverse cellular responses, including cancer cell resistance to chemotherapy and protection against inflammatory responses to Pseudomonas aeruginosa Here, we report the use of photoactive probes to identify MVP as a target of the N-(3-oxo-dodecanoyl) homoserine lactone (C12), a quorum sensing signal of certain proteobacteria including P. aeruginosa. A treatment of normal and cancer cells with C12 or other N-acyl homoserine lactones (AHLs) results in rapid translocation of MVP into lipid raft (LR) membrane fractions. Like AHLs, inflammatory stimuli also induce LR-localization of MVP, but the C12 stimulation reprograms (functionalizes) bioactivity of the plasma membrane by recruiting death receptors, their apoptotic adaptors, and caspase-8 into LR. These functionalized membranes control AHL-induced signaling processes, in that MVP adjusts the protein kinase p38 pathway to attenuate programmed cell death. Since MVP is the structural core of large particles termed vaults, our findings suggest a mechanism in which MVP vaults act as sentinels that fine-tune inflammation-activated processes such as apoptotic signaling mediated by immunosurveillance cytokines including tumor necrosis factor-related apoptosis inducing ligand (TRAIL).

The synthesis of a series of cocaine-fluorophore conjugates and the functional evaluation of the compounds against single-chain Fv antibodies are described. It was determined that the GNC-F2 fluorophore reproduced affinity constants obtained using [(super 3)H]-labeled cocaine.

Cocaine addiction continues to be a major health and social problem in the United States and other countries. Currently used pharmacological agents for treating cocaine abuse have proved inadequate, leaving few treatment options. An alternative is to use protein-based therapeutics that can eliminate the load of cocaine, thereby attenuating its effects. This approach is especially attractive because the therapeutic agents exert no pharmacodynamic action of their own and therefore have little potential for side effects. The effectiveness of these agents, however, is limited by their inability to act directly within the CNS. Bacteriophage have the capacity to penetrate the CNS when administered intranasally. Here, a method is presented for engineering filamentous bacteriophage to display cocaine-binding proteins on its surface that sequester cocaine in the brain. These antibody-displaying constructs were examined by using a locomotor activity rodent model to assess the ability of the phage-displayed proteins to block the psychoactive effects of cocaine. Results presented demonstrate a strategy in the continuing efforts to find effective treatments for cocaine addiction and suggest the application of this protein-based treatment for other drug abuse syndromes.

The chemo enzymatic synthesis of two G (sub M3)-derived reagents and their use in the panning of a phage-displayed human single-chain Fv (scFv) antibody library derived from the blood of cancer patients is described. The result is a significant step toward effective immunotherapies for the treatment of cancer.

A revised synthesis of the fimbrolide as well as a direct comparison between the fimbrolide and alkyl-DPD analogues is presented. The studies have shown that alkyl-DPD analogues are more potent inhibitors of quorum sensing (QS) in Vibrio harveyi and Salmonella typhimurium, the two organisms with defined Al-2 QS systems.

A comprehensive study of the expanded spectrum of [C.sub.12]-TA antibacterial activity against microbial competitors encountered by Pseudomonas aeruginosa in nature as well as significant human pathogens is presented. The obtained results provide insight into the evolved QS machinery of P. aeruginosa for a dual-function which involve both to signal others of the same species and also to defend against host immunity and competing bacteria.

The discovery of a class of synergistic compounds toward the quorum sensing (QS) of Vibrio harveyi, as well as a remarkable switch in the biological transmission of AI-2-based QS in Salmonella typhimurium stemming from the addition of methylene groups to the C1 position of (S)-4,5-dihydroxy-2,3-pentanedione (DPD) is described. This class of compounds has represented a starting point for the development of broad range modulators of QS and identification of unknown AI-2 receptor proteins.

A set of cyclic peptide libraries expressed on the pIX coat protein of M13 filamentous phage, which were screened against melanoma cells is prepared and utilized, using whole-cell phage panning method to discover peptides that specifically bind to and are internalized into cancer cells. This showed that cyclic peptide Pep42 is a very important tool in construction of drug conjugates, designed to selectively kill malignant cancer cells.

The stability of several N-acyl L-homoserine lactones (AHLs) is investigated under physiological conditions to guide the hapten design and a number of AHL analogues and their corresponding ring-opened hydrolysis products are synthesized. It was found that RS2IG9 possessed the ability to inhibit 3-oxo-C12-AHL-based quorum sensing (QS) signaling and it might be used as a tool for investigating 3-oxo-C12-AHL-based QS.

The preparation and kinetics of the first catalytic phage-displayed therapeutic with suitable rates to treat cocaine addiction are described. Cocaine is a powerful stimulant, the most reinforcing of all drugs, and acts as an indirect dopamine agonist by blocking the dopamine transporter in the reward center of the brain.