1. A double-lumen perfusion technique was used to study the effect of a wide range of concentrations of the dipeptide glycyl-L-alanine and its constituent amino acids on water and electrolyte absorption from iso-osmotic solutions in the upper jejunum of normal human subjects. 2. There was no significant absorption of water and electrolytes from sodium chloride solution (150 mmol/l) but the pres...

The effect of synthetic muramyl dipeptide on glycosaminoglycan synthesis in cultured rat costal chondrocytes was examined. Muramyl dipeptide alone had no effect on the glycosaminoglycan synthesis of rat chondrocytes, whereas Escherichia coli lipopolysaccharide and interleukin 1 alpha inhibited glycosaminoglycan synthesis in a dose dependent manner. Muramyl dipeptide, when added to chondrocyte c...

Non-enzymic protein glycosylation (glycation) plays important roles in ageing and in diabetes and its secondary complications. Dietary constituents may play important roles in accelerating or suppressing glycation. It is suggested that carnivorous diets contain a potential anti-glycating agent, carnosine (beta-alanyl-histidine), whilst vegetarians may lack intake of the dipeptide. The possible ...

Molecular dynamics (MD) simulations were used to compare the structures of the chiral molecular micelles (MM) poly-(sodium undecyl-(L,L)-leucine-valine) (poly(SULV)) and poly-(sodium undecyl-(L,L)-valine-leucine) (poly (SUVL)). Both MM contained polymerized surfactant monomers tenninated by chiral dipeptide headgroups. The study was undertaken to investigate why poly(SULV) is generally a better...

We investigated native structures and mitogenic properties of pokeweed lectin-D isoforms (PL-D1 and -D2) on human peripheral blood lymphocytes along with other isolectins (PL-A to -C). Both native PL-D isoforms appeared to behave as monomers. PL-D2 proliferated the lymphocytes like PL-C, whereas PL-D1 had no mitogenicity. PL-D1 acquired mitogenic activity after trimming of the C-terminal dipept...

In this study, we report that the insertion of a pseudoproline dipeptide for the solid-phase peptide synthesis of wild-type Phospholamban protein (WT-PLB) has two important advantages. First, it disrupts the formation of different secondary structures, which is responsible for poor couplings during the preparation of highly aggregated sequences. Second, it enhances the purities and solubility o...

In this research, dipeptide (his-β-alanine) and porphyrin derivatives were choosen for comparing chelating ability of toxic metals such as Al3+, Cu2+, Hg2+ and Pb2+ in vitro. The reason for choosing these two compounds is that both of them are naturally present in biological systems and comparison of chelating ability of these two compounds has not yet been done. Synthesis and comparison of kin...

For better understanding of conformational stability of the dipeptide model HCO—Gly—L—Leu—NH2,ab initio and DFT computations at HF/6-31G(4 6-311++G(d,p) and B3LYP/6-31G(d) levels oftheory were carried out. Geometry optimization of the dipeptide within the leucine (Leu) side chainangles (x2 ,x2) resulted in three stable conformations as followings: anti-anti, the most stable one,(Xi = 180°, x2 =...

Priming of mice with complexes of antigen coupled to muramyl dipeptide and monoclonal anti-muramyl dipeptide antibodies enhanced the adjuvant activity of muramyl dipeptide on the humoral response to the antigen. The enhancement did not occur with free (uncoupled) muramyl dipeptide and required the presence of an adjuvant-active hapten within the complex as well as the Fc fragment of the monoclo...