The Cyanobacterial Ribosomal-Associated Protein LrtA from sp. PCC 6803 Is an Oligomeric Protein in Solution with Chameleonic Sequence Properties.

The LrtA protein of sp. PCC 6803 intervenes in cyanobacterial post-stress survival and in stabilizing 70S ribosomal particles. It belongs to the hibernating promoting factor (HPF) family of proteins, involved in protein synthesis.

The chromatin nuclear protein NUPR1L is intrinsically disordered and binds to the same proteins as its paralogue.

NUPR1 is a protumoral multifunctional intrinsically disordered protein (IDP), which is activated during the acute phases of pancreatitis. It interacts with other IDPs such as prothymosin α, as well as with folded proteins such as the C-terminal region of RING1-B (C-RING1B) of the Polycomb complex; in all those interactions, residues around Ala33 and Thr68 (the 'hot-spot' region) of NUPR1 intervene. Its paralogue, NUPR1L, is also expressed in response to DNA damage, it is p53-regulated, and its expression down-regulates that of the gene.

Concentration-controlled formation of myoglobin/gold nanosphere aggregates.

Gold nanoparticles are being increasingly proposed as biotechnological tools for medical diagnosis and therapy purposes. Their safety for human beings and the environment is therefore becoming an emerging issue, which calls for basic research on the interactions between nanostructured gold particles and biological materials, including physicochemical studies of model systems. In this Article, we focus on the "reaction products" of a widely known nanoparticle type, citrate-capped 30 nm gold nanospheres, with a model protein, horse myoglobin.

The C-terminal sterile alpha motif (SAM) domain of human p73 is a highly dynamic protein, which acquires high thermal stability through a decrease in backbone flexibility.

The α-splice variant of p73 (p73α), a homologue of the tumour suppressor p53, has close to its C terminus a sterile alpha motif (SAM), SAMp73, that is involved in protein-biomolecule interactions. The conformational stability of SAMp73 is low (∼5 kcal mol(-1)), although its thermal stability is high. To explain this high thermostability, we studied the dynamics of SAMp73 over a wide range of GdmCl (guanidine hydrochloride) concentrations and temperatures by NMR relaxation, NMR hydrogen-exchange (HX) and fluorescence lifetime approaches.

Nucleotide-induced conformational transitions in the CBS domain protein MJ0729 of Methanocaldococcus jannaschii.

Nucleotide-binding cystathionine β-synthase (CBS) domains function as regulatory motifs in several proteins distributed through all kingdoms of life. This function has been proposed based on their affinity for adenosyl-derivatives, although the exact binding mechanisms remain largely unknown. The question of how CBS domains exactly work is relevant because in humans, several genetic diseases have been associated with mutations in those motifs.

Aggregation of antitumoral drug emodin on Ag nanoparticles: SEF, SERS and fluorescence lifetime experiments.

We have studied the fluorescence and Raman emission of the anthraquinone drug emodin immobilized molecules on nanostructured silver surfaces, prepared through two different methods. Two different pHs (pH = 10 and pH = 6) have been used. The dye aggregation favors SEF at pH = 6, whereas quenching of fluorescence is observed at pH = 10, due to the short distance between emodin and Ag particles.

Identification of the antitumoral drug emodin binding sites in bovine serum albumin by spectroscopic methods.

Using SERS, fluorescence, circular dichroism and stopped-flow, we have unequivocally characterized the binding sites of emodin in bovine serum albumin. Emodin interacts with protein through two different binding sites corresponding to Sudlow's sites 1 and 2. Site 2, where the binding drug presents, in the cavity, a form between neutral and mono-anionic species slightly displaced to the neutral one, is the primary interaction site, with higher association binding constant, and hence, higher affinity than the other binding site.