Growth of Microcystis aeruginosa could be inhibited significantly within 24 h by the extracellular substances prepared from Aeromonas sp. strain FM. During the treatment, the concentration of extracellular soluble carbohydrates increased significantly in algal culture. Morphological and ultrastructural changes in M. aeruginosa cells, including breakage of the cell surface, secretion of mucilage...

SUMMARY ASAP is a web tool designed to search for specific dipeptides, tripeptides and tetrapeptides in a protein sequence database. The server allows for: (a) identification of frequent and infrequent peptides and the creation of peptide probability tables for a given database of sequences (GenerNet program), (b) determination of the compatibility of an amino-acid sequence to the given peptide...

The human multidrug resistance protein 1 (MRP1) is a primary active transporter of reduced (GSH) and oxidized glutathione, as well as GSH-, glucuronate-, and sulfate-conjugated organic anions. In addition, the transport of certain MRP1 substrates is stimulated by the presence of GSH. To evaluate the structural features of GSH required for interaction with the protein, we investigated the abilit...

The blending together of synthetic chemistry with natural product biosynthesis represents a potentially powerful approach to synthesis; to enable this, further synthetic tools and methodologies are needed. To this end, we have explored the first Sonogashira cross-coupling to halotryptophans in water. Broad reaction scope is demonstrated and we have explored the limits of the scope of the reacti...

A double side-reaction, consisting in the formation of Fmoc-beta-Ala-OH and Fmoc-beta-Ala-AA-OH, during the preparation of Fmoc protected amino acids (Fmoc-AA-OH) with Fmoc-OSu is discussed. Furthermore, the new Fmoc-2-MBT reagent is proposed for avoiding these side-reactions as well as the formation of the Fmoc-dipeptides (Fmoc-AA-AA-OH) and even tripeptides, which is another important side-re...

A933 acylase, which is involved in exchange of the pantothenyl substituent of OA-6129 carbapenems with acetyl CoA, was characterized as an L-amino acid acylase with a molecular weight of 100,000 (+/- 8,000) and a pI value of 5.1. The highest L-amino acid acylase activity of A933 acylase was observed at 37 degrees C and pH 7 approximately 7.5 for N-chloroacetyl-L-phenylalanine. Unlike other amin...

Peptides that inhibit angiotensin-converting enzyme (ACE) were isolated from alpha-zein hydrolysate prepared with thermolysin. Their chemical structures were identified by Edman degradation and fast-atom bombardment mass spectrometry. Most of them were found to be tripeptides such as Leu-Arg-Pro, Leu-Ser-Pro, and Leu-Gln-Pro, having IC50 values of 0.27, 1.7, and 1.9 microM, respectively. These ...

A novel class of mannosylated adamantyltripeptides, general formula of which is α-ManOCH2CH(CH3)CO-AdGly-L-Ala-D-isoGln, were prepared, characterized, and their possible immunomodulatory properties investigated in some preliminary tests in vivo. All newly synthesized glycopeptides comprise in their structure the adamantylglycyl moiety linked to the dipeptide L-Ala-D-isoGln, as well as mannose. ...

Here we evaluated the use of internal reference compounds for the rapid assessment of reactions performed in solid-phase. An internal reference compound (commercially available) was bound to the resin, together with the substrate, and cleaved with the products after completion of the reaction. The peak area of the reference compound in the HPLC-UV chromatograms can be correlated directly with t...

Two orthogonal peptide combinatorial libraries were screened to discover inhibitors of Tc80 protease, a novel target from Trypanosoma cruzi involved in host cell invasion. These libraries were composed of 15,625 structurally diversified tripeptides, partitioned in 125 mixtures. The screening led to a low micromolar inhibitor which was actually an HF cleavage by-product H-Ipe-D-Tic-D-Glu(S-parat...