2 research outputs found
Pronucleotide Probes Reveal a Diverging Specificity for AMPylation vs UMPylation of Human and Bacterial Nucleotide Transferases
AMPylation is a post-translational modification utilized
by human
and bacterial cells to modulate the activity and function of specific
proteins. Major AMPylators such as human FICD and bacterial VopS have
been studied extensively for their substrate and target scope in vitro. Recently, an AMP pronucleotide probe also facilitated
the in situ analysis of AMPylation in living cells.
Based on this technology, we here introduce a novel UMP pronucleotide
probe and utilize it to profile uninfected and Vibrio parahaemolyticus infected human cells. Mass spectrometric analysis of labeled protein
targets reveals an unexpected promiscuity of human nucleotide transferases
with an almost identical target set of AMP- and UMPylated proteins.
Vice versa, studies in cells infected by V. parahaemolyticus and its effector VopS revealed solely AMPylation of host enzymes,
highlighting a so far unknown specificity of this transferase for
ATP. Taken together, pronucleotide probes provide an unprecedented
insight into the in situ activity profile of crucial
nucleotide transferases, which can largely differ from their in vitro activity
Pronucleotide Probes Reveal a Diverging Specificity for AMPylation vs UMPylation of Human and Bacterial Nucleotide Transferases
AMPylation is a post-translational modification utilized
by human
and bacterial cells to modulate the activity and function of specific
proteins. Major AMPylators such as human FICD and bacterial VopS have
been studied extensively for their substrate and target scope in vitro. Recently, an AMP pronucleotide probe also facilitated
the in situ analysis of AMPylation in living cells.
Based on this technology, we here introduce a novel UMP pronucleotide
probe and utilize it to profile uninfected and Vibrio parahaemolyticus infected human cells. Mass spectrometric analysis of labeled protein
targets reveals an unexpected promiscuity of human nucleotide transferases
with an almost identical target set of AMP- and UMPylated proteins.
Vice versa, studies in cells infected by V. parahaemolyticus and its effector VopS revealed solely AMPylation of host enzymes,
highlighting a so far unknown specificity of this transferase for
ATP. Taken together, pronucleotide probes provide an unprecedented
insight into the in situ activity profile of crucial
nucleotide transferases, which can largely differ from their in vitro activity