Month: July 2022

Stefanie Neun, Paul Brear, Eleanor Campbell, Theodora Tryfona, Kamel El Omari, Armin Wagner, Paul Dupree, Marko Hyvönen, Florian Hollfelder

Nature Chemical Biology. Online ahead of print. 07 July 2022 Jul.
DOI: 10.1038/s41589-022-01071-x
Pubmed: 35799064

PDB coordinates:
7QE1 (3D view), 7QE2 (3D view), 7QEF (3D view), 7QEA (3D view), 7QG4 (3D view), 7QEE (3D view)

Abstract

The abundance of recorded protein sequence data stands in contrast to the small number of experimentally verified functional annotation. Here we screened a million-membered metagenomic library at ultrahigh throughput in microfluidic droplets for β-glucuronidase activity. We identified SN243, a genuine β-glucuronidase with little homology to previously studied enzymes of this type, as a glycoside hydrolase 3 family member. This glycoside hydrolase family contains only one recently added β-glucuronidase, showing that a functional metagenomic approach can shed light on assignments that are currently ‘unpredictable’ by bioinformatics. Continue reading →

Yanislava Karusheva, Matt Ratcliff, Audrey Melvin, Alexander Moerseburg, Naveed Sattar, Peter Barker, Keith Burling, Anna Backmark, Robert Roth, Lutz Jermutus, Esther Guiu-Jurado, Matthias Blueher, Paul Welsh, Marko Hyvönen, Stephen O’Rahilly

The Journal of Applied Laboratory Medicine, Advance Article 07 July 2022.
DOI: 10.1093/jalm/jfac055
MedRxiv preprint DOI: 022.01.03.22268655

Abstract

Genetic variants in proteins can interfere with measurement of their circulating concentrations. Given the growing biomedical importance of GDF-15, we wished to establish whether a common histidine to aspartate variant present in position 6 of the mature GDF-15 protein (H202D variant) interfered with its measurement by two commonly used immunoassays. We first examined the detectability of recombinant monomers, homodimers and heterodimers of GDF-15 by assays and/or reagents used in two widely used immunoassays (Roche Elecsys GDF-15 and the R&D antibody combinations used in their Quantikine and DuoSet ELISAs). The Roche assay detected the H and D containing peptides similarly but the assays based on the R&D reagents consistently underreported concentrations of the D-containing variant peptide. Measurements of plasma concentrations of GDF-15 in genotyped human participants showed that the R&D reagents reported values in heterozygotes were ~25% lower, and in homozygotes, 50% lower than the Roche assay. Continue reading →