The application of methods developed mostly in this laboratory permitted the synthesis of the fully S,Nprotected heptapeptides N-carbobenzoxy-S-trityl-L-cysteinylS-diphenylmethylL cysteinyl-LalanylglycylLvalyl-S-trityl-L-cysteinyl-L-serine methyl ester (VIII, Figure 21, N-t-butyloxycarbonyl-S-trityl-L-cysteiny1-Sdiphenylmethyl-LcysteinylL-alanylglycyl-LvalylStrityl-L-cysteinyl-L-serine methyl e...

Bacillus coagulans has been found to produce several surfactins that are powerful lipopeptide surfactants. Four main components with molecular weights 1007, 1021 and 1035 Da were separated. Their structures have been confirmed by spectrometric and spectroscopic studies and by acid hydrolysis. The compounds were found to represent two pairs of surfactin isoforms in which beta-hydroxy-iso-C14 or ...

The octapeptide 61-68 and the heptapeptide 61-67 do not possess the protected conformation of C-fragment. In contrast with the protracted exposure to membrane enzymes required to form [methioninelenkephalin from C-fragment, the short peptides rapidly undergo this conversion. The corresponding tripeptide Thr-Ser-Glu and dipeptide Thr-Ser were isolated. The results suggest that C-fragment is degr...

this paper presents the results of a series of monotonic and post-cyclic triaxial tests carried out on a clay specimen and three types of clay-sand mixed specimens. the focus of the paper is on the post-cyclic mechanical behavior of the mixed specimens, as compared to their monotonic behavior. analyses of the tests results show that cyclic loading degrade undrained shear strength and deformatio...

The heptapeptide angiotensin-(1-7) is considered to be a biologically active endproduct of the renin-angiotensin system. This angiotensin, which is devoid of the most known actions of angiotensin II such as induction of drinking behavior and vasoconstriction, has several selective effects in the brain and periphery. In the present article we briefly review recent evidence for a physiological ro...

mixed clayey soils occur as mixtures of sand (or gravel) and clay in widely varying proportions. their engineering behavior has not been comprehensively studied yet. an experimental program, comprising monotonic, cyclic, and post-cyclic triaxial tests was undertaken on compacted clay-granular material mixtures, having different proportions of clay and sand or gravel. this paper presents the res...

The thermodynamics of folding and unfolding of a beta-heptapeptide in methanol solution has been studied at four different temperatures, 298 K, 340 K, 350 K, and 360 K, by molecular dynamics simulation. At each of these temperatures, the 50-ns simulations were sufficient to generate an equilibrium distribution between a relatively small number of conformations (approximately 10(2)), showing tha...