Structure of Merkel Cell Polyomavirus Capsid and Interaction with Its Glycosaminoglycan Attachment Receptor.

Merkel cell polyomavirus (MCPyV) is a human double-stranded DNA tumor virus. MCPyV cell entry is unique among members of the polyomavirus family as it requires the engagement of two types of glycans, sialylated oligosaccharides and sulfated glycosaminoglycans (GAGs). Here, we present crystallographic and cryo-electron microscopic structures of the icosahedral MCPyV capsid and analysis of its glycan interactions via nuclear magnetic resonance (NMR) spectroscopy.

Structural analysis and knock-out of a Burkholderia pseudomallei homolog of the eukaryotic transcription coactivator PC4.

Homologs of the eukaryotic transcription coactivator PC4, which also functions in DNA repair and oxidative stress, were recently identified in prokaryotes. Crystallographic analysis of BPSL1147, a putative homolog from the pathogen Burkholderia pseudomallei K96243, reveals a highly conserved core structure and suggests a nucleic acid binding mode similar to that of PC4. Knock-out and complementation experiments do not reveal distinguishing phenotypes under normal growth conditions or in the presence of H2O2, arguing against a critical role in repair or the oxidative stress response of Burkholderia.