-Acetyl Migration within the Sialic Acid Side Chain: A Mechanistic Study Using the Nanoreactor.

Many disease-causing viruses target sialic acids on the surface of host cells. Some viruses bind preferentially to sialic acids with -acetyl modification at the hydroxyl group of C7, C8, or C9 on the glycerol-like side chain. Studies of proteins binding to sialosides containing -acetylated sialic acids are crucial in understanding the related diseases but experimentally difficult due to the lability of the ester group.

SARS-CoV-2 and MERS-CoV Spike Protein Binding Studies Support Stable Mimic of Bound 9--Acetylated Sialic Acids.

Many disease-causing viruses target sialic acids (Sias), a class of nine-carbon sugars known to coat the surface of many cells, including those in the lungs. Human beta coronaviridae, known for causing respiratory tract diseases, often bind Sias, and some preferentially bind to those with 9--Ac-modification. Currently, co-binding of SARS-CoV-2, a beta coronavirus responsible for the COVID-19 pandemic, to human Sias has been reported and its preference towards α2-3-linked Neu5Ac has been shown.

An Audio Personal Health Library of Clinic Visit Recordings for Patients and Their Caregivers (HealthPAL): User-Centered Design Approach.

Background: Providing digital recordings of clinic visits to patients has emerged as a strategy to promote patient and family engagement in care. With advances in natural language processing, an opportunity exists to maximize the value of visit recordings for patients by automatically tagging key visit information (eg, medications, tests, and imaging) and linkages to trustworthy web-based resources curated in an audio-based personal health library.

Objective: This study aims to report on the user-centered development of HealthPAL, an audio personal health library.

Reversible -Acetyl Migration within the Sialic Acid Side Chain and Its Influence on Protein Recognition.

-Acetylation is a common naturally occurring modification of carbohydrates and is especially widespread in sialic acids, a family of nine-carbon acidic monosaccharides. -Acetyl migration within the exocyclic glycerol-like side chain of mono--acetylated sialic acid reported previously was from the C7- to C9-hydroxyl group with or without an 8--acetyl intermediate, which resulted in an equilibrium that favors the formation of the 9--acetyl sialic acid. Herein, we provide direct experimental evidence demonstrating that -acetyl migration is bidirectional, and the rate of equilibration is influenced predominantly by the pH of the sample.

A combined NMR, MD and DFT conformational analysis of 9-O-acetyl sialic acid-containing GM3 ganglioside glycan and its 9-N-acetyl mimic.

O-Acetylation of carbohydrates such as sialic acids is common in nature, but its role is not clearly understood due to the lability of O-acetyl groups. We demonstrated previously that 9-acetamido-9-deoxy-N-acetylneuraminic acid (Neu5Ac9NAc) is a chemically and biologically stable mimic of the 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2) of the corresponding sialoglycans. Here, a systematic nuclear magnetic resonance (NMR) spectroscopic and molecular dynamics (MD) simulation study was undertaken for Neu5,9Ac2-containing GM3 ganglioside glycan (GM3-glycan) and its Neu5Ac9NAc analog.