Publications by authors named "Elsa Silva-Lopez"

Selective modification of proteins at cysteine residues by reactive oxygen, nitrogen or sulfur species formed under physiological and pathological states is emerging as a critical regulator of protein activity impacting cellular function. This review focuses primarily on protein sulfenylation (-SOH), a metastable reversible modification connecting reduced cysteine thiols to many products of cysteine oxidation. An overview is first provided on the chemistry principles underlining synthesis, stability and reactivity of sulfenic acids in model compounds and proteins, followed by a brief description of analytical methods currently employed to characterize these oxidative species.

View Article and Find Full Text PDF

Planar solid supported lipid membranes that include an intervening bovine serum albumen (BSA) cushion can greatly reduce undesirable interactions between reconstituted membrane proteins and the underlying substrate. These hetero-self-assemblies reduce frictional coupling by shielding reconstituted membrane proteins from the strong surface charge of the underlying substrate, thereby preventing them from strongly sticking to the substrate themselves. The motivation for this work is to describe the conditions necessary for liposome adsorption and bilayer formation on these hetero-self-assemblies.

View Article and Find Full Text PDF
Article Synopsis
  • Click reactions are a fast way to join two molecules together, especially useful in creating radiopharmaceuticals by linking radioactive metals to biological targeting molecules.
  • The study focused on using a specific click reaction (thiol-ene) involving a radioactive complex [M(I)(CO)3](+) with a targeting molecule containing a thiol, exploring two methods: click then chelate and chelate then click.
  • Initial experiments used benzyl mercaptan to evaluate both methods, showing that both approaches produced the same product, and various DPA ligand designs were tested to see how the structure influenced the reaction's effectiveness, leading to promising results in incorporating radioactive metals into biomolecules.
View Article and Find Full Text PDF

Described is the synthesis of 5-hydroxytryptamine-tetramethylrhodamine (5HT*); an indole nitrogen linked fluorescent conjugate of serotonin. Through a series fluorescence quenching experiments and experiments in the presence of a known competitive antagonist (Granisetron), it was shown that 5HT* specifically binds to purified homo-pentameric type-3 human serotonin receptors (5HT(3A)). The measured dissociation constant and Hill coefficient are K(d) = 83 ± 3 nM and n = 3.

View Article and Find Full Text PDF

Androgen receptors are overexpressed in most primary and metastatic prostate cancers. A series of single photon emission computed tomography imaging agents (SPECT) utilizing the organometallic radioactive imaging species, fac-99mTc(OH(2))(3)(CO)(3)+, were prepared on the basis of the structure of Flutamide, a potent nonsteroidal antiandrogen prostate cancer drug. Novel bifunctional chelate-linked Flutamide analogues were prepared using a newly developed universal alkylating reagent, 2-bromo-N-[4-nitro-3-(trifluoromethyl)phenyl]-acetamide, 1.

View Article and Find Full Text PDF

Reaction of [NEt4]2[ReBr3(CO)3] with 2,4-pentanedione (acac) yields a complex of the type fac-Re(acac)(OH2)(CO)3 (1) under aqueous conditions. 1 was further reacted with a monodentate ligand (pyridine) to yield a fac-Re(acac)(pyridine)(CO)3 complex (2). Complex 1 was found to react with primary amines to generate a Schiff base (imine) in aqueous solutions.

View Article and Find Full Text PDF