Polyphosphate Biology:

Polyphosphate (PolyP) is a chain of up to thousands of phosphate residues. PolyP is found in all kingdoms of life, including bacteria, yeasts and human cells. In microorganisms, PolyP is thought to serve as an energy storage and a phosphate reserve, and may play a role in bacterial virulence, gene expression and stress response, among others. In mammalian cells, which contain much lower amounts of PolyP than microorganisms, PolyP is involved in many cell processes such as apoptosis, cell proliferation and energy metabolism.

PolyP synthesis is achieved by polyphosphate kinases while polyphosphatases degrade PolyP chains, but these enzymes are yet to be identified in mammalian cells. In 2015, PolyP was also discovered as a novel post translational modification (PTM) added to lysine residues in yeast (Azevedo et al., 2015). Polyphosphorylation occurs on PASK motifs (poly acidic serine and lysine rich motifs) present in some proteins. Polyphosphorylation is non-enzymatic. We are interested in the regulation of polyphosphorylation as a PTM. We have also become intrigued by polyphosphate biogenesis and storage. Finally, we are always interested in uncovering new and unexpected functions for polyphosphate.

Relevant Papers:

Bentley-DeSousa et al. 2018; Bentley-DeSousa et al. 2019; Downey, 2019; McCarthy et al. 2020; Bondy-Chorney et al. 2020. Denoncourt et. al 2021, Baijal et al. 2021a Baijal et al. 2021b, Bentley-DeSousa et al. 2021, McCarthy et al. 2022

Our work in the area of polyP uses bacterial, yeast, and cell culture models.

Watch a recent seminar of Mike talking about polyP