Welcoming Claude Into the Classroom Risks the Soul of Education

Faculty have a responsibility to protect classrooms as a training ground for thinking, and proliferating LLMs endanger this core mission of the University.

chicagomaroon.com

Using X-ray Crystallography and 1,n-ADEQUATE NMR to Revise the Structures of Highly Substituted Aromatic Natural Products: The Absolute Configuration of Formicamycin Congeners

Formicamycins and their biosynthetic precursors, the fasamycins, form part of the phenylnaphthacenoid family of polyketide natural products. A recent atroposelective total synthesis of formicamycin H brought into question our original stereochemical assignment of the axially chiral linkage between C-6 and C-7. To address this, we obtained an X-ray crystal structure for formicamycin H that unambiguously confirmed our original assignment as the Sa atropisomer. X-ray structures for multiple additional fasamycins and formicamycins confirmed that this is common to all congeners. However, these studies identified a compounded error made by us whereby several structures previously reported as para-methoxy were found to have ortho-methoxy groups on the hanging E-ring. To address this for congeners that did not crystallize or gave nondiffracting crystals, we turned to the surprisingly underutilized 1,n-ADEQUATE NMR experiment. In total, we generated X-ray structures for 15 phenylnaphthacenoid metabolites and by combining these results report the corrected structures for three formicamycins, six fasamycins, and three biosynthetic lactone intermediates, noting that several revised fasamycin structures now match previously reported naphthacemycins. Our results highlight the utility of 1,n-ADEQUATE experiments for regiochemical determination in polysubstituted aromatic molecules. Moreover, our investigations uncovered a potential deracemization step during biosynthesis of the formicamycin framework.

pubs.acs.org

Innovative proximity labeling platform illuminates how cholesterol interacts inside cells – UCLA

Cholesterol plays a central role in cell health, influencing membrane fluidity, curvature, and signaling. To maintain proper cholesterol levels, cells rely on tightly regulated transport systems that move cholesterol between membranes and organelles. However, many of the proteins involved in sensing, binding, and trafficking cholesterol—and how they dynamically interact—remain poorly understood.

chemistry.ucla.edu

Mapping the Earth’s Hidden Fungal Kingdom | Joint Genome Institute

Leveraging massive comparative genomics to decode millions of mystery genes and lay a future-ready foundation

jgi.doe.gov

Recent discoveries on the acquisition of the highest levels of human performance

Scientists have long debated the origins of exceptional human achievements. This literature review summarizes recent evidence from multiple domains on the acquisition of world-class performance. We re...

science.org

These archaea built a distinct genetic code to put pyrrolysine in proteins

That feat has synthetic biologists excited

cen.acs.org

Recurrent acquisition of nuclease-protease pairs in antiviral immunity

Antiviral immune systems diversify by integrating new genes into existing pathways, creating new mechanisms of viral resistance. We identified genes encoding a predicted nuclease paired with a trypsin-like protease repeatedly acquired by multiple, ...

ow.ly

Synthesis of Collinoketones via Biomimetic [6 + 4] Cycloaddition

Cycloadditions are among the most powerful reactions for constructing molecular complexity. The archetypal example is the [4 + 2] (Diels–Alder) cycloaddition, which efficiently furnishes cyclohexene d...

pubs.acs.org

Metabolic controls on the carbon isotope fractionations of bacterial fermentation | PNAS

Microbial fermentation facilitates the initial breakdown of organic matter into small molecules and is thought to be the rate-limiting step of anox...

pnas.org

Prizes must recognize machine contributions to discovery

The future of science will be written by humans and machines together. Awards should reflect that reality.

nature.com

The 2025 chemistry Nobel goes to MOFs

Susumu Kitagawa, Richard Robson and Omar M. Yaghi win the prize for developing metal–organic frameworks

cen.acs.org

New electron diffraction strategy could make it easier to study solvated organic microcrystals

The approach combines carbon liquid cells and rapid data acquisition to study solvated molecules at room temperature

chemistryworld.com

The Radical S-Adenosyl-l-methionine Enzyme HydE Forms an Fe(I)Fe(I) Dimer En Route to the [FeFe] Hydrogenase H-Cluster

[FeFe] hydrogenases are highly efficient metalloenzymes that catalyze hydrogen conversion via a sophisticated active site cofactor known as the H-cluster. Biosynthesis of its [2Fe]H subcluster, which ...

pubs.acs.org

Scientists’ role in defending democracy

The United States’ democratic leadership, commitment to freedom of expression, and investment in the pursuit of knowledge have long enabled its preeminence in science and technology. Yet today we are ...

science.org