Nonribosomal peptide synthetase; part of the gene cluster that mediates the biosynthesis of echinocandin B, a fungal lipidated cyclic hexapeptide that acts as an antifungal agent (PubMed:22998630). Linoleoyl-AMP, produced by the fatty-acyl-AMP ligase ecdI, is transferred to the initiation carrier domain (T0) of ecdA (PubMed:22998630). The linoleoyl-S-phosphopantetheinyl-T0 is sequentially extended with L-ornithine, L-threonine, L-proline, L-homotyrosine, L-threonine, and 4R-methyl-L-proline to form the linear hexapeptide (PubMed:22998630). Thereafter, the terminal condensation (C7) performs macrocyclization of the NRPS product and the cyclic scaffold is released from ecdA (PubMed:22998630). All six of the amino acid residues are hydroxylated, including 4R,5R-dihydroxy-L-ornithine, 4R-hydroxyl-L-proline, 3S,4S-dihydroxy-L-homotyrosine, and 3S-hydroxyl-4S-methyl-L-prolin (PubMed:22998630). In the pathway, all the hydroxylation reactions are proposed to occur following completion of the cyclic peptide, so the unhydroxylated precursor produced by ecdA will undergo six rounds of hydroxylation (PubMed:22998630). Five hydroxylase genes (ecdG, ecdH, ecdK, htyE and htyF) are embedded within the echinocandin B (ecd) and L-homotyrosine (hty) clusters (PubMed:22998630). Antifungal biosynthesis. The NRPS ecdA is a multimodular enzymatic assembly that contains 20 domains With the following architecture: T0-CAT1-CAT2-CAT3-CAT4-CAT5-CAT6-C7 (PubMed:22998630). The initiation carrier domain (T0) binds linoleoyl-AMP prodiced by ecd I (PubMed:22998630). The 6 CAT modules correspond respectively to each of the 6 amino acid monomers incorporated (L-ornithine, L-threonine, L-proline, L-homotyrosine, L-threonine, and 4R-methyl-L-proline) (PubMed:22998630). Finally the last condensation domain (C7) performs the macrocyclization of the linear hexapeptide (PubMed:22998630). Impairs the production of echinocandin B (PubMed:22998630). Due to their effectiveness as antifungal agents, echinocandin derivatives can be used for the treatment of human invasive candidiasis (PubMed:22998630). Belongs to the NRP synthetase family.