Disruption of Macrodomain Protein SCO6735 Increases Antibiotic Production in Streptomyces coelicolor

Abstract

ADP-ribosylation is a post-translational modification that can alter the physical and chemical properties of target proteins and that controls many important cellular processes. Macrodomains are evolutionarily conserved structural domains that bind ADP-ribose derivatives and are found in proteins with diverse cellular functions. Some proteins from the macrodomain family can hydrolyze ADP-ribosylated substrates and therefore reverse this post-translational modification. Bacteria and Streptomyces, in particular, are known to utilize protein ADP-ribosylation, yet very little is known about their enzymes that synthesize and remove this modification. We have determined the crystal structure and characterized, both biochemically and functionally, the macrodomain protein SCO6735 from Streptomyces coelicolor. This protein is a member of an uncharacterized subfamily of macrodomain proteins. Its crystal structure revealed a highly conserved macrodomain fold. We showed that SCO6735 possesses the ability to hydrolyze PARP-dependent protein ADP-ribosylation. Furthermore, we showed that expression of this protein is induced upon DNA damage and that deletion of this protein in S. coelicolor increases antibiotic production. Our results provide the first insights into the molecular basis of its action and impact on Streptomyces metabolism.

ADP‐ribosylation: new facets of an ancient modification

“…SCO6735 is a macrodomain protein closest to human proteins ALC1 and TARG1 . In vitro SCO06735 can remove MARylation from glutamate residues, yet structural and biochemical characterization indicate a mechanism distinct from any other known macrodomain hydrolases .…”

“…SCO6735 is a macrodomain protein closest to human proteins ALC1 and TARG1 . In vitro SCO06735 can remove MARylation from glutamate residues, yet structural and biochemical characterization indicate a mechanism distinct from any other known macrodomain hydrolases . Although SCO6735 physiological substrate is still unknown, its expression is under the control of a RecA‐independent DNA damage inducible promoter and upregulated upon UV‐induced DNA damage , thus indicating a role in DNA damage response.…”

“…In vitro SCO06735 can remove MARylation from glutamate residues, yet structural and biochemical characterization indicate a mechanism distinct from any other known macrodomain hydrolases . Although SCO6735 physiological substrate is still unknown, its expression is under the control of a RecA‐independent DNA damage inducible promoter and upregulated upon UV‐induced DNA damage , thus indicating a role in DNA damage response. Moreover, SCO6735 is possibly involved in the regulation of antibiotic production and disruption of the Sco6735 gene was shown to increase actinorhodin production .…”

Poly(ADP-Ribose) Polymerases in Host-Pathogen Interactions, Inflammation, and Immunity

“…Indeed, these proteins mediate resistance to interferon signaling (170), promote virulence, and suppress the innate immune response during coronavirus infection (171)(172)(173). Specific protein substrates have been identified for a few macrodomains (169,(174)(175)(176)(177), but many remain unidentified to date. Some macrodomains have divergent biochemical activities, such as nucleic acid binding or protein/protein interaction, suggesting that these readers and erasers, like PARPs, are multifunctional (168,(178)(179)(180).…”

“…In nitrogen-fixing bacteria, the MARylation modification regulates nitrogenase (reviewed in reference 187). In Bacillus subtilis and Streptomyces griseus ADP-ribosylation contributes to sporulation (188,189), and in Streptomyces coelicolor it regulates antibiotic production (174). The S. coelicolor SCO5461 protein was experimentally demonstrated to carry out MARylation.…”