An Unusual Aspartic Acid Cluster in the Reovirus Attachment Fiber σ1 Mediates Stability at Low pH and Preserves Trimeric Organization.

ABSTRACT: The reovirus attachment protein σ1 mediates cell attachment and receptor binding and is thought to undergo conformational changes during viral disassembly. σ1 is a trimeric filamentous protein with an α-helical coiled-coil tail, a triple-β-spiral body, and a globular head. At the trimer interface, the head domain features an unusual and conserved aspartic acid cluster, which forms the only significant intratrimer interactions in the head and must be protonated to allow trimer formation. To define the role of pH on σ1 stability and conformation, we tested its domains over a wide range of pH values. We show that all domains of σ1 are remarkably thermostable, even at the low pH of the stomach. We determined the optimal pH for stability to be between pHs 5 and 6, a value close to the pH of the

SUBMITTER: Glorani G 

PROVIDER: S-EPMC9044935 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature