Nonribosomal peptide synthetase; part of the gene cluster that mediates the biosynthesis of asterriquinone CT5, a natural product that displays potential biological activities including antitumor and insulin mimic activities (PubMed:23841722). The nonribosomal peptide synthetase atqA is responsible for the production of the benzoquinone derivative didemethylasterriquinone D (DDAQ D), via condensation of 2 indole pyruvic acid (IPA) molecules (PubMed:23841722). The symmetric connectivity of the 2 IPA molecules is thought to arise by head-to-tail dual Claisen condensations catalyzed by the TE domain of atqA (By similarity). DDAQ D represents the core structure of asterriquinones and is further modified by yet unidentified tailoring enzymes to lead to the production of asterriquinone CT5 (PubMed:23841722). Secondary metabolite biosynthesis. AtqA has an A-T-TE domain architecture (Probable). The adenylation (A) domain recognizes and activates the aryl acid substrates, and loads them onto the thiolation (T) domain (Probable). The thioesterase (TE) domain shares the missing condensation (C) domain function, and is responsible for condensation and final product release (Probable). Abbolishes the production of asterriquinone CT5. Belongs to the NRP synthetase family.