Amino acids phospholamban

Phospholamban is a homopentamer, each subunit consisting of 52 amino acids. The subunits consist of a 30-residue N-terminal hydrophilic region containing the phosphorylation sites, and a C-terminal hydro-phobic domain responsible for oligomerization and for anchoring phospholamban in the membrane. The N-terminal domain is a basic amphiphilic a-helix, which resembles the calmodulin-binding domain of many proteins (Chiesi efa/., 1991). Phospholamban is phosphorylated at serine-16 by cAK and cGK and at threonine-17 by Ca +/calmodulin-dependent protein... 

However, phospholamban protein was undetectable in pig aorta (Raeymaekers and Jones, 1986 Eggermont etfl/., 1990b). To our knowledge, published data on myometrium are lacking. The amino acid sequence of phospholamban of pig stomach smooth muscle determined from cDNA sequencing is identi-... 

The high stability of the biarsenical-tetracysteine complex and the sensitivity of its fluorescence polarization to localized protein dynamics complex has recently been used to probe the structure of the pentameric oligomer of phospholamban [17], a key regulator of contractility in the heart. Tetracysteine sites were formed at three internal sites within the n-helical region involved in oligomerization by mutation of existing amino acids at positions 5, 6,... 

Structural changes in the lipid bilayer upon insertion of the transmembrane domain of the membrane-bound protein phospholamban (PLB) were studied using P and solid state NMR. Phospholamban is a 52-amino acid integral membrane protein that regulates the flow of Ca " ions in cardiac muscle cells. Solid state NMR experiments were carried out to study the behavior of lipid bilayers in the presence of the hydrophobic PLB at different temperatures. P NMR was used to study the different phases formed by phospholipid membranes. Simulations of the P NMR spectra were carried out to reveal the formation of different vesicle sizes upon PLB insertion. Molecular order parameters were calculated by performing solid state NMR studies on deuterated phospholipid bilayers. 

Phospholamban (PEN) is a single-pass 52-amino acid membrane protein that interacts with the Ca-ATPase (SERCA) in cardiac muscle. Wild-type PEN, existing as a pentamer, takes the pinwheel topology as the predominant conformation with the cytoplasmic domain interacting with the membrane surface [262—264]. The PEN monomer (AFA-PEN), in which three TM cysteines are replaced by A36, F41 and A46, is functionally active and in equilibrium between ordered (T) and disordered (R) states [265,266] N backbone and Ile-methyl dispersion data indicate that residues within domain la (residues 1-16), the loop (17-22), and domain lb (23-30) of PEN undergo is-ms dynamics (feex=6100 800 s at 17 °C) [267]. 

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