The influence of chemical modification on the morphology of crystalline ATPase aggregates was analyzed in sarcoplasmic reticulum (SR) vesicles. The Ca2+-ATPase forms monomer-type (P1) type crystals in the E1 and dimer-type (P2) crystals in the E2 conformation. The P1 type crystals are induced by Ca2+ or lanthanides; P2 type crystals are observed in Ca2+-free media in the presence of vanadate or...

Recent advances in the development of microfabricated lab-on-a-chip analysis systems have enhanced the feasibility and capabilities of in situ chemical and biochemical analyzers. While a wide variety of bio-organic molecules can be probed, we have focused our initial studies on the development of an amino acid analyzer with the hypothesis that extraterrestrial life would be based on homochiral ...

Surfactant dysfunction in acute lung injury has been postulated as a result of free radical damage to lipid and protein components. This study examines whether transition metals with different redox potentials and different binding affinities for lipids and proteins affect interfacial properties differently. Purified whole calf lung surfactant (CLS) was incubated with 0.125 mM Fe2+, Fe3+, Fe3+-...

A rapid and sensitive method for determining protein concentrations using fluorescamine has been characterized for use in the analysis of intact lipoproteins. It was shown that there is no interference with the assay due to the presence of lipid-associated turbidity or primary amine content. The assay was shown to be sensitive to as little as 0.3 p g of lipoprotein and to yield similar results ...

Graphene oxide (GO) is a promising 2D material with complex chemical structure which characterization remains as challenge. The widely-accepted of GO includes epoxides, hydroxyls and carboxylic acids. Recently, alkene groups have been used for selective functionalization. Despite the different efforts that exist to elucidate exact structure, composition main functionalities fairly limited. By k...

An ion-exchange chromatographic procedure has been developed for the separation and fluorometric detection of the urinary polyamines 1,3-diaminopropane, putrescine, spermidine, cadaverine, and spermine. The polyamines were separated on a 15 x0.45 cm cation-exchange column (70”) employing a combined pH-salt gradient. The separation conditions were designed to enable utilization of the sensitive ...

A method was adapted to determine proteolytic activity in dry-cured ham using fluorescamine-specific labelling of N-terminal α-amino groups of peptides and amino acids. Fluorescence of the complex was measured using a microplate procedure and optimum excitation and emission wavelengths of 375nm and 475nm, respectively. A new proteolysis index (PI) was defined as the percentage ratio of the N-te...