Streamlining Global Germplasm Exchange: Integrating Scientific Rigor and Common Sense to Exclude Phantom Agents from Regulation.

This collaborative work by over 180 researchers from 40+ countries addresses the challenges posed by "phantom agents"-putative pathogenic agents named in literature without supporting data on their existence. Those agents remain on regulatory lists, creating barriers in trade and plant certification. Historically identified based solely on symptoms, these agents lack isolates or sequence data, making reliable detection or risk assessment impossible.

Next generation sequencing-based MSI scoring predict benefit in mismatch repair deficient tumors treated with nivolumab: follow-up on NCI-MATCH arm Z1D.

Purpose: Mismatch repair deficient (dMMR) tumors have demonstrated favorable responses to immune checkpoint inhibition targeting PD-1. However, more in-depth identification of predictors of response could further refine patient selection for immunotherapy treatment.

Experimental Design: We undertook integrated evaluation performed on samples collected from 28 of 42 patients enrolled on the NCI-MATCH arm Z1D trial that evaluated PD-1 inhibition treatment with nivolumab in patients with non-colorectal dMMR tumors.

Batrachopolyenes: Volatile Norsteroids from Femoral Scent Glands of Frogs.

Steroid hormones are C-C-sterane derivatives, featuring the typical 6-6-6-5 ring system. Here we report on a novel C-steroid ring system named batrachane with a contracted A-ring resulting in a 5-6-6-5 ring arrangement. The isolation, structural elucidation, and total synthesis of three members of the novel batrachopolyene family occurring in the tropical frog genus Odontobatrachus is reported.

A novel 4,4-dimethylcytidine in the archaeal ribosome enhances hyperthermophily.

Ribosome structure and activity are challenged at high temperatures, often demanding modifications to ribosomal RNAs (rRNAs) to retain translation fidelity. LC-MS/MS, bisulfite-sequencing, and high-resolution cryo-EM structures of the archaeal ribosome identified an RNA modification, 4,4-dimethylcytidine (mC), at the universally conserved C918 in the 16S rRNA helix 31 loop. Here, we characterize and structurally resolve a class of RNA methyltransferase that generates mC whose function is critical for hyperthermophilic growth.