The prenyltransferase FtmPT1 from Aspergillus fumigatus is involved in the biosynthesis of fumitremorgin-type alkaloids and catalysed the regular C2-prenylation of brevianamide F (cyclo-L-Trp-L-Pro). It has been shown that FtmPT1 also accepted a number of other tryptophan-containing cyclic dipeptides and prenylated them, in the presence of dimethylallyl diphosphate, at C-2 of the indole nucleus...

A new S9 family aminopeptidase derived from the actinobacterial thermophile Acidothermus cellulolyticus was cloned and engineered into a transaminopeptidase by site-directed mutagenesis of catalytic Ser(491) into Cys. The engineered biocatalyst, designated aminolysin-A, can catalyze the formation of peptide bonds to give linear homo-oligopeptides, hetero-dipeptides, and cyclic dipeptides using ...

Soft X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy have been used to probe the electronic and adsorption properties of two cyclic dipeptides, i.e. cyclo(glycyl-histidyl) and cyclo(phenylalanyl-prolyl), on Au(111) and Cu(110) surfaces. The core level spectra show chemical shifts which indicate weak chemisorption on Au(111), and stronge...

The effect of a selected tripeptide, Z-d-Phe-Phe-Arg(NO(2)) (SV-4814) on the kinetics of lysis of green monkey erythrocytes by measles virus hemolysin suggested conditions of competitive inhibition. SV-4814 prevented not only hemoglobin release, but also the preceding leakage of K(+) through the cell membrane. The capacity of 12 different dipeptides, 6 tripeptides, including SV-4814, and 4 tetr...

Most of polypeptides containing α,β-dehydroamino acids have important biological activity, so exploration of synthetic method has practical significance. In this paper, dipeptides were prepared from l-threonine by protecting of c-terminal allyl acetate, and condensing reaction with a series of N-Boc amino acid. Then, treatment of dipeptides obtained with DMAP, (Boc)2O and tetramethylguanidine i...

In the experiments reported in the present communication, these studies have been extended with special reference to the specificity of the enzyme toward the dipeptide used as replacement agent. It had been suggested (1) that the value of pKz’ of a dipeptide is a determining factor in the efficiency with which it can participate in a transamidation reaction at ‘a given pH. This suggestion has b...

First-principles quantum calculations for anharmonic vibrational spectroscopy of three protected dipeptides are carried out and compared with experimental data. Using hybrid HF/MP2 potentials, the Vibrational Self-Consistent Field with Second-Order Perturbation Correction (VSCF-PT2) algorithm is used to compute the spectra without any ad hoc scaling or fitting. All of the vibrational modes (135...

Equilibrium constants for the adsorption of the first water molecule on six protonated dipeptides (Gly-Gly+H(+), Gly-Ala+H(+), Ala-Gly+H(+), Ala-Ala+H(+), Pro-Gly+H(+), and Gly-Trp+H(+)) have been measured as a function of temperature, and DeltaH(o) and DeltaS(o) determined. Density functional theory calculations were performed for both the unsolvated peptides and the peptide water complexes at...

Redox-active tyrosine residues play important roles in long-distance electron reactions in enzymes, including prostaglandin H synthase, galactose oxidase, ribonucleotide reductase, and photosystem II. Magnetic resonance and vibrational spectroscopy provide methods with which to study the structures of redox-active amino acids in proteins. In this report, ultraviolet photolysis was used to gener...