Structural Deformations in Cucurbit[n]urils: Analysis, Host-Guest Dependence, and Automated Ellipticity Measurements Using ElliptiCB[n].

Cucurbit[n]urils (CB[n]s) are cyclic macrocycles with rich host-guest chemistry. In many cases, guest binding in CB[n]s results in host structural deformations. Unfortunately, measuring such deformations remains a major challenge, with only a handful of manual estimations reported in the literature.

Bacterial vampirism mediated through taxis to serum.

Bacteria of the family Enterobacteriaceae are associated with gastrointestinal (GI) bleeding and bacteremia and are a leading cause of death, from sepsis, for individuals with inflammatory bowel diseases. The bacterial behaviors and mechanisms underlying why these bacteria are prone to bloodstream entry remain poorly understood. Herein, we report that clinical isolates of non-typhoidal serovars, , and are rapidly attracted toward sources of human serum.

Navigating contradictions: Salmonella Typhimurium chemotactic responses to conflicting effector stimuli.

Chemotaxis controls swimming motility and colonization of many intestinal bacteria, but how enteric pathogens navigate the complex chemical landscape of the gut, which contains contradictory chemoattractant and chemorepellent stimuli, remains poorly understood. We find Typhimurium requires chemotactic sensing of two opposing signals present in the intestinal lumen-the microbiota metabolite and bacteriostatic chemorepellent indole, and the nutrient chemoattractant l-Ser-for efficient invasion of colonic tissue. Despite feces being the major biological source of indole, accumulating to millimolar levels, non-typhoidal are strongly attracted to fecal material because chemoattraction to l-Ser and other attractants override indole chemorepulsion.

Ancestral Reconstruction and the Evolution of Protein Energy Landscapes.

A protein's sequence determines its conformational energy landscape. This, in turn, determines the protein's function. Understanding the evolution of new protein functions therefore requires understanding how mutations alter the protein energy landscape.

Bacterial vampirism mediated through taxis to serum.

Bacteria of the family Enterobacteriaceae are associated with gastrointestinal (GI) bleeding and bacteremia and are a leading cause of death, from sepsis, for individuals with inflammatory bowel diseases. The bacterial behaviors and mechanisms underlying why these bacteria are prone to bloodstream entry remains poorly understood. Herein, we report that clinical isolates of non-typhoidal Salmonella enterica serovars, Escherichia coli, and Citrobacter koseri are rapidly attracted toward sources of human serum.