Research articles

Three homologous cytochrome P450s from monoterpene indole alkaloid-producing plants enable the identification of sarpagan bridge enzyme, which catalyzes either cyclization or aromatization to yield sarpagan or β-carboline alkaloids, respectively.

The antibacterial microvionin contains two new lanthipeptide modifications, a triamino-dicarboxylic acid (avionin) and an N-terminal guanidino fatty acid, that lead to the establishment of the lipolanthine natural product class.

The structure of a monotopic polyprenol phosphate phosphoglycosyl transferase, PglC, reveals how it interacts with the bacterial membrane and coordinates a reaction between membrane-embedded and soluble substrates during glycoconjugate assembly.

The crystal structure of a methyltransferase domain embedded within an interrupted adenylation domain provides insight into how a nonribosomal peptide synthetase N-methylates amino acid precursors for their incorporation into the peptide product.

The discovery of cytochrome P450 monooxygenases that catalyze oxidative demethylation of 6-O-methyl-d-galactose reveals a new activity of cytochrome P450 enzymes and their role in polysaccharide biomass degradation in marine bacteria.

A de novo–designed protein, Syn-F4, hydrolyzes the siderophore ferric enterobactin both in vitro and in Escherichia coli cells, enabling a bacterial strain lacking the essential natural enterobactin esterase to grow in iron-limited medium.

Biosynthesis of the antibiotic sulfazecin involves N-sulfonation in trans of the tripeptide intermediate before synthesis of the β-lactam ring by a noncanonical thioesterase domain, demonstrating a new enzymatic route to the azetidinone moiety.

In Pseudoalteromonas rubra, an unclustered biosynthetic gene encodes a di-iron oxygenase-like enzyme that catalyzes regiospecific C–H activation and cyclization of prodigiosin, yet is unrelated to the Rieske oxygenases that produce other cyclized prodiginines.

A toxic conformation of disease-linked huntingtin protein with expanded polyQ is degraded more slowly than the other conformations, as it is less able to engage the autophagy machinery, explaining its higher toxicity compared to other conformations.

A nonribosomal peptide synthetase involved in colibactin biosynthesis utilizes S-adenosylmethionine as a nonproteinogenic amino acid building block, which is then converted into the cyclopropane moiety that is critical for colibactin's genotoxic activity.

Cpf1 is a CRISPR effector protein that exhibits greater genome editing specificity than Cas9 nuclease. Cpf1 from two distinct bacteria selectively processes RNA polymerase II transcripts into crRNA fragments competent for genome editing.

Characterization of the heme-dependent enzyme KtzT reveals it to be the elusive enzyme responsible for nitrogen–nitrogen bond formation during the biosynthesis of piperazate, a building block for some nonribosomal peptide natural products.

A genetically encoded unnatural amino acid analog and its acidic deprotection enable the site-specific incorporation of phosphotyrosine (pTyr) into proteins such as ubiquitin, where it can be used to study the function of this phosphorylated residue.

Characterization of the gene cluster for omphalotin biosynthesis reveals that they are ribosomally synthesized peptides whose internal α-N-methyl groups are installed by a methyltransferase fused to the precursor peptide substrate.

A synthetic biology system composed of light-wavelength-responsive genetic regulators, signal-processing circuits and pigment-production pathways have resulted in an Escherichia coli strain that can record color images in RGB format.

Most microbial biosynthetic gene clusters are inactive under laboratory culture conditions. A CRISPR–Cas9 genome-editing approach in Streptomyces species enables the targeted activation of silent gene clusters and production of encoded natural products.

Crystallographic analysis of human O-GlcNAc hydrolase (hOGA) fragments containing the catalytic domain, including structures in complex with known inhibitors, suggests that OGA is functional as a dimer and defines opportunities for structure-based drug design.

Crystal structures of human O-GlcNAc hydrolase (hOGA) fragments show that hOGA's dimeric structure is organized by swapping of an α-helical element and reveal features of inhibitor binding to the catalytic domain.

Characterization of a family of Stigonematales (Stig) cyclases that catalyze stereoselective intramolecular C–C bond formation reveals the enzymatic origins of the complex stereochemical patterns in hapalindole and fischerindole alkaloids.

An automated method for solid-phase polypeptide synthesis capitalizes on rapid amide bond formation to enable the production of multiple traditionally difficult-to-synthesize sequences with both high yield and high purity.