A bioactivity guided study of a cf. Caldora penicillata species, collected during a 2013 expedition to the Pacific island of Saipan, Northern Mariana Islands (a commonwealth of the USA), led to the isolation of a new thiazoline-containing alkaloid, laucysteinamide A (1). Laucysteinamide A is a new monomeric analogue of the marine cyanobacterial metabolite, somocystinamide A (2), a disulfide-bon...

Laccase from Pleurotus florida was immobilized on agarose/agar/polyacrylamide gel, glass beads and alginate beads. The laccase entrapped agarose gel exhibited 88% of immobilization yield as compared to laccase immobilization on glass bead (72%) and Ba-alginate (50%). The enzyme embodied in agarose gel showed greater storage stability at 16°C as compared to enzyme immobilized on glass beads and ...

Although the microbial formation of a variety of polypeptides possessing antibiotic activities has been known for some time, the biosynthesis of these compounds has as yet received little attention. Not only is the mechatnism of formation of these biologically active compounds of interest in itself, but the biosyntheses of these polypeptides are potential systems for investigating the general p...

A pseudo-octahedral complex of high-spin Fe(II), bis(2,2'-bi-2-thiazoline)bis(isothiocyanato)iron(II), which has a cis-FeN'2N4 chromophore, has been investigated by high-frequency, high-field electron paramagnetic resonance (HFEPR). Complementary Mössbauer and DC magnetic susceptibility studies were also performed. HFEPR spectra of powder samples were recorded at frequencies up to 700 GHz and o...

Total synthesis of the (S)-stereoisomer of telomestatin (1) was accomplished. (S)-Telomestatin exhibited potency four times that of the natural product, (R)-telomestatin, which was the most potent telomerase inhibitor previously reported. In the circular dichroism spectral analysis of the complexes possessing randomly structured single-stranded d[TTAGGG](4) oligonucleotide, (S)-telomestatin, li...

Natural products comprise a diverse array of molecules, many of which are biologically active. Most natural products are derived from combinations of polyketides, peptides, sugars, and fatty-acid building blocks. Peptidic macrocycles have attracted attention as potential therapeutics possessing cell permeability, stability, and easy-to-control variability. Here, we show that enzymes from the pa...

Combining biosynthetic enzymes from multiple pathways is an attractive approach for producing molecules with desired structural features; however, progress has been hampered by the incompatibility of enzymes from unrelated pathways and intolerance toward alternative substrates. Ribosomally synthesized and posttranslationally modified peptides (RiPPs) are a diverse natural product class that emp...