β-N-Methylamino-l-alanine (BMAA) is a potential neurotoxin associated with the aquatic environment. Validated analytical methods for the quantification of both free and total concentrations of BMAA were used in an investigation of seafood purchased from different grocery stores in Uppsala, Sweden. The analysis was performed using ultra high performance liquid chromatography-electrospray ionizat...

The NAD-dependent isocitrate dehydrogenase [threo-D(S)-isocitrate:NAD(+) oxidoreductase (decarboxylating); EC 1.1.1.41] from pig heart is a multisubunit enzyme with a molecular weight of approximately 340,000. Electrophoresis of the enzyme in 10% polyacrylamide gels containing sodium dodecyl sulfate reveals two discrete bands with molecular weights of 41,000 and 39,000. The two bands exhibit ap...

Cone snails, genus Conus, are predatory marine snails that use venom to capture their prey. This venom contains a diverse array of peptide toxins, known as conotoxins, which undergo a diverse set of posttranslational modifications. Amidating enzymes modify peptides and proteins containing a C-terminal glycine residue, resulting in loss of the glycine residue and amidation of the preceding resid...

It is widely appreciated that the isotype of the H chain of the Ab molecule influences its functional properties. We have now investigated the contribution of the isotype of the L chain to the structural and functional properties of the Ab molecule. In these studies, the L chain variable region of a murine anti-dansyl Ab was joined to either human kappa or lambda constant region domains and exp...

We demonstrate Förster resonance energy transfer from dehydroergosterol to dansylated lecithin in lecithin-cholesterol vesicles and characterize the vesicles in the presence of the pro-nucleating enzyme, phospholipase C (PLC). Exposure to phospholipase C causes a temporary decrease in the dehydroergosterol to dansyl fluorescence ratio followed by an increase to and above the initial value. The ...

Dansyl phosphatidylethanolamine (DPE) (dansyl, 5dimethylaminonaphthalene-1-sulfonyl) was incorporated into human plasma very low density lipoproteins (VLDL). Concomitant with its lipolysis, DPE-VLDL undergoes a greater than %fold fluorescence enhancement, a large increase in fluorescence polarization, and a 20 nm blue shifl in the wavelength of its emission maxima. Based on fluorescence quenc...

N-Dansyl-2-oxopyrrolidine, a competitive inhibitor with respect to ATP, was used as a probe of the nucleotide binding site of pyridoxal kinase. It binds to an hydrophobic region of the catalytic site with a KD = 6 microM. Time emission anisotropy measurements yielded a rotational correlation time of 38 ns for the bound inhibitor. N-Dansyl-2-oxopyrrolidine is immobilized by strong interactions w...

Three different bichromophoric compounds (1-3) containing an aminomethyl anthracene moiety linked to a second chromophore (pyrene, 4-nitrobenzo-2-oxa-1,3-diazole (NBD) and dansyl) through a valine-derived pseudopeptidic spacer have been prepared and their fluorescent properties studied. The results obtained show that upon irradiation the photophysical behavior of these probes involves electroni...

Fluorescence studies on the interaction, with porcine pepsin, of oligopeptides bearing a mansyl (Mns, 6-(N-methylanilino)-2-naphthalenesulfonyl) or dansyl (Dns, 5-dimethylaminonaphthalene-1-sulfonyl) group at the NH2 or COOH terminus have provided further evidence showing that the probe group is drawn into the extended active site largely as a consequence of the specific binding of the peptide ...