The catechol moiety of obafluorin is essential for antibacterial activity.

Obafluorin is a antibacterial natural product that inhibits threonyl-tRNA synthetase (ThrRS). It acts as a broad-spectrum antibiotic against a range of clinically relevant pathogens and comprises a strained β-lactone ring decorated with catechol and 4-nitro-benzyl moieties. The catechol moiety is widespread in nature and its role in the coordination of ferric iron has been well-characterised in siderophores and Trojan horse antibiotics.

Heterologous Expression of the Formicamycin Biosynthetic Gene Cluster Unveils Glycosylated Fasamycin Congeners.

Formicamycins and their biosynthetic intermediates the fasamycins are polyketide antibiotics produced by KY5 from a pathway encoded by the biosynthetic gene cluster. In this work the ability of M1146 and the ability of Δ to heterologously express the biosynthetic gene cluster were assessed. This led to the identification of eight new glycosylated fasamycins modified at different phenolic groups with either a monosaccharide (glucose, galactose, or glucuronic acid) or a disaccharide comprised of a proximal hexose (either glucose or galactose), with a terminal pentose (arabinose) moiety.

Assessing the Toxicity and Mitigating the Impact of Harmful Blooms in Eutrophic Waters of the Norfolk Broads.

is a toxin-producing microalga, which causes harmful algal blooms globally, frequently leading to massive fish kills that have adverse ecological and economic implications for natural waterways and aquaculture alike. The dramatic effects observed on fish are thought to be due to algal polyether toxins, known as the prymnesins, but their lack of environmental detection has resulted in an uncertainty about the true ichthyotoxic agents. Using qPCR, we found elevated levels of and its lytic virus, PpDNAV-BW1, in a fish-killing bloom on the Norfolk Broads, United Kingdom, in March 2015.

Discovery and characterisation of an amidine-containing ribosomally-synthesised peptide that is widely distributed in nature.

Ribosomally synthesised and post-translationally modified peptides (RiPPs) are a structurally diverse class of natural product with a wide range of bioactivities. Genome mining for RiPP biosynthetic gene clusters (BGCs) is often hampered by poor annotation of the short precursor peptides that are ultimately modified into the final molecule. Here, we utilise a previously described genome mining tool, RiPPER, to identify novel RiPP precursor peptides near YcaO-domain proteins, enzymes that catalyse various RiPP post-translational modifications including heterocyclisation and thioamidation.

Comparison of Fit Between Zirconia and Metal Copings Fabricated Conventionally or Using Different CAD/CAM Techniques.

This study was designed to assess the fit of cobalt chromium copings fabricated using direct metal laser sintering and to compare with copings fabricated from nickel chromium (traditional casting) and zirconia (milled from partially sintered blanks). For both cobalt chromium and zirconia groups, impressions were generated using direct or indirect digitization. There were 5 experimental groups of 12 copings fabricated for a prepared maxillary right molar.