Volume 13 Issue 7, July 2017

Enzymology and structural and functional characterization of some FAD-dependent monooxygenases provide insights into degradation of tetracycline antibiotics, but also show unexpected features of substrate recognition, reaction mechanism, and competitive inhibition.

Lipid II embodies the bricks used to build the essential bacterial cell wall component peptidoglycan. A facile new procedure for preparation of species-specific Lipid II in high yields can now be used to unlock the door to antibiotic discovery.

A variety of chemical and enzymatic techniques, each with their own considerations for use, have been developed for the site-selective bioconjugation of desirable moieties to proteins via the unique handle of the N terminus.

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.

The bicyclic disulfide–containing compound thiolutin has broad antimicrobial activity and targets the essential proteasomal deubiquitinase Rpn11 and other metalloproteases, leading to inhibition of enzymatic activity through a mechanism involving zinc chelation.

An integrated homology modeling and docking strategy, IPHoLD, is used to predict protein–ligand binding sites and poses, allowing blind prediction of GPCR–ligand conformations and design of dopamine receptors with novel ligand-binding selectivity.

Membrane curvature induces sorting of GPCRs within live-cell-membrane protrusions, and the curvature-dependent sorting is affected by agonist binding. Thermodynamic modeling suggests that this is due to an energetic drive to match receptor shape and elasticity to membrane curvature.

Structural and functional characterization of tetracycline-inactivating enzymes reveals that inhibitors act by locking the enzyme in an unproductive state by restricting substrate-driven conformational dynamics that are important for catalysis.

In vitro reconstitution of five enzymes elucidates the biosynthetic pathway of obafluorin (Obi) and reveals that ObiF uses an unusual thioesterase domain to cyclize the product to a strained β-lactone during release from the NRPS assembly line.

A conserved threonine in medium-chain dehydrogenases/reductases is essential to suppress the formation of an inhibitory side product, which suggests that it functions to destabilize competing transition states rather than to promote positive catalysis.

The use of protein microarrays containing human methyllysine effector molecules enabled discovery of a potent and selective inhibitor of the interaction of the Tudor-domain-containing protein Spindlin1 with H3K4me3.

X-ray crystallographic analysis of the mouse protein-O-fucosyltransferase POFUT1 combined with average structural map analysis demonstrate that POFUT1 specifically recognizes only one of the four EGF-like domain types found in nature.

The design and mutagenesis of an α-helix-containing monomeric miniprotein, PPα-Tyr, provide insights into weak noncovalent CH–π interactions that help define and stabilize folded proteins and protein–ligand interactions.

The use of a refined chemical library called the CeMM library of unique drugs (CLOUD) identified a synergistic interaction between flutamide and phenprocoumon in decreasing the growth of prostate cancer cells by regulating androgen receptor stability.

The structure of the hydrogenase-maturation protein HydF in the holo form with its [4Fe-4S] cluster reveals a labile glutamate ligand that allows binding of artificial 2Fe subcluster mimics, thus endowing HydF with its own hydrogenase activity.

PF-9366 inhibits Mat2A by binding to an allosteric site that overlaps with the binding site of Mat2B, altering the active site and supporting a model in which Mat2B can be either an inhibitor or an activator of Mat2A, depending on methionine and SAM levels.

The isolation of Lipid II, accumulated as a result of chemical probe treatment, enables the reconstitution of crosslinked peptidoglycan biosynthesis and a direct transpeptidase assay for PBP2 inhibition by β-lactams.

Intracellular G_s-cAMP signaling from β₁-adrenergic receptors residing in the Golgi represents ‘location bias’, a new form of GPCR functional selectivity. Inactive Golgi-localized receptors can be activated by some β₁-targeting drugs.

A crystal structure of the RNA aptamer Mango bound to a thiazole orange–derived fluorophore reveals a three-tiered G-quadruplex structure, which, together with three flap-like nucleotides, constrains the fluorophore into its active conformation.