Protein and Peptide Letters - Volume 8, Issue 6, 2001

Some amyloid-derived peptides show their toxic effects only after a long “aging” period performed several days at pH 7.4 and 37 C for cluster formation. Our experiments show that long aging of beta-amyloid[25-35] under physiological conditions results in peptide bond cleavage between Asn27 and Lys28. Relatively short incubation time (24 hours) and absence of Ca2+ ions prevent peptide cleavage and results in good ag Read More

Although thermodynamic formalisms for protein denaturation have been established for some time, available software programs for deconvolution of DSC data exhibit various limitations. These include enforcing a constant deltaCp(T), linear heat capacity functions, and so on. We have developed a Windows based program that allows greater flexibility, speed and accuracy than previously available programs for the analysis of DSC Read More

A new modification of Monte-Carlo algorithm was suggested for the simulation of hierarchical protein folding. When applied to 2D lattice model of 12-member peptide this method allows observing complex kinetic folding behavior with the formation of clustered intermediates.

Temporin A is one of a group of 31 structurally similar antibiotic peptides isolated from the skins of anurans, 10 of which were isolated from the European red frog, Rana temporaria. The synthesis and bacteriological study of temporin A and 8 analogs were reported previously, and this article describes the synthesis and analyses of 11 new temporin A analogs, and a cecropin A-temporin A hybrid peptide

alpha-Haemolysin is an extracellular protein toxin (107KDa) produced by certain pathogenic strains of Escherichia coli. It can bind to lipid bilayers and produce membrane disruption in cell and model membranes. Protein secondary structure predictions suggest an amphipathic helix conformation for the membrane-interacting domain of HlyA, and no potential transmembrane segments. In this paper, we investigated Read More

Five analogues of neurotensin(NT:Pyr-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) were prepared by the solid-phase method and their comparative anorectic effects on food intake in rats were examined. Among them, [Phe(NO2)3,11]-NT and [Phe(4F)3,11]-NT showed stronger anorectic activity than that of the parent peptide but [Tyr(Me)3,11]-NT was less active than the parent peptide. On the contrary, the oth Read More

One cDNA of a thrombin-like enzyme named acutinII was amplified by RT-PCR from the venom gland of the Agkistrodon acutus snake. AcutinII shows high similarity to acutin, the other thrombin-like enzyme from Agkistrodon acutus snake in nucleotide and amino acid sequences except it is shorter by 16 amino acid at the C-terminus. The catalytic residues and disulfide bridges of acutinII were deduced. AcutinII was expresse Read More

The lectin from the seeds of Canavalia brasiliensis (Con Br) was tested for its renal effects using the isolated perfusion rat kidney method. Three different doses were examined (3,10 and 30 microgram / ml), which were compared with a control group. The control group was perfused with only Krebs-Henseleit solution containing 6 percent BSA. Con Br caused diuresis and natriuresis, with a mild alteration on the perfusion pressu Read More

Nine species of Leguminosae seeds from Amazon forest have been screened for trypsin and chymotrypsin inhibitory activity. The species involved were Cassia basselari, Cassia grandis, Cassia occidentalis, Dialium guianense, Inga fagifolia, Inga rubiginosa, Inga umbratica, Inga velutina and Mimosa guillandinae. Extracts from all the species, except I. umbratica, contained significant activity against trypsin, chymotrypsin and b Read More

A thermostable DNA photolyase from an extremely thermophilic bacterium, Thermus thermophilus HB8 has been crystallized by the hanging drop vapor diffusion method using NH4H2PO4 as a precipitant. The hexagonal crystals were grown to a size of 0.4 mm in length. X-ray diffraction experiments show the crystals to belong to the hexagonal space group P6 5 22 or P6 1 22 with the unit cell dimensions of a=b=113.6 A, Read More

Staphylokinse (Sak) is a plasminogen activator for the treatment of patients with thrombolitic disorders. However, the highly purified Sak can form dimer in solution, which is believed to be the cause for the increased antigenicity. Here we report a new crystal form with two molecules in an asymmetric unit, suggesting there maybe a dimer packing in crystal. The crystal belongs to the orthorhombic space group P2 1 2 1 2 1 Read More