Cooperation between a T Domain and a Minimal C-Terminal Docking Domain to Enable Specific Assembly in a Multiprotein NRPS.

ABSTRACT: Non-ribosomal peptide synthetases (NRPS) produce natural products from amino acid building blocks. They often consist of multiple polypeptide chains which assemble in a specific linear order via specialized N- and C-terminal docking domains (^N/C DDs). Typically, docking domains function independently from other domains in NRPS assembly. Thus, docking domain replacements enable the assembly of "designer" NRPS from proteins that normally do not interact. The multiprotein "peptide-antimicrobial-Xenorhabdus" (PAX) peptide-producing PaxS NRPS is assembled from the three proteins PaxA, PaxB and PaxC. Herein, we show that the small ^C DD of PaxA cooperates with its preceding thiolation (T₁ ) domain to bind the ^N DD of PaxB with very high affinity, establishing a structural and thermodynamical basis for this unprecedented docking interaction, and we test its functional importance in vivo in a truncated PaxS assembly line. Similar docking interactions are apparently present in other NRPS systems.

SUBMITTER: Watzel J 

PROVIDER: S-EPMC8251938 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature