Linear dicentric chromosomes in bacterial natural isolates reveal common constraints for replicon fusion.

Unlabelled: Multipartite bacterial genome organization can confer advantages including coordinated gene regulation and faster genome replication but is challenging to maintain. lineages often contain a circular chromosome (Ch1), a linear chromosome (Ch2), and multiple plasmids. We previously observed that in some stocks of the lab model strain C58, Ch1 and Ch2 were fused into a linear dicentric chromosome.

Singlets-Driven Photoredox Catalysts: Transforming Noncatalytic Red Fluorophores to Efficient Catalysts.

Red-light absorbing photoredox catalysts offer potential advantages for large-scale reactions, expanding the range of usable substrates and facilitating bio-orthogonal applications. While many red-light absorbing/emitting fluorophores have been developed recently, functional red-light absorbing photoredox catalysts are scarce. Many photoredox catalysts rely on long-lived triplet excited states (triplets), which can efficiently engage in single electron transfer (SET) reactions with substrates.

Syntheses of optically active monapterin, 7,8-dihydromonapterin, and 5,6,7,8-tetrahydromonapterin from l-xylose.

We describe the syntheses of monapterin, dihydromonapterin and tetrahydromonapterin in optically active forms. The syntheses involved the condensation of l-xylose with phenylhydrazine, providing a hydrazone derivative. The reaction of the resulting hydrazone with triamino-pyrimidinone followed by oxidation of the resulting pteridinone with molecular oxygen furnished pterin containing a hydroxylated side chain.