Nonribosomal peptide synthase; part of the gene cluster that mediates the biosynthesis of hydroxamate-containing siderophores that play a critical role in virulence via intracellular iron acquisition during macrophage infection (PubMed:18404210). Siderophore biosynthesis. Expression is induced during iron deprivation (PubMed:18404210). Also induced in response to reactive nitrogen species (PubMed:16030248). NRP synthetases are composed of discrete domains (adenylation (A), thiolation (T) or peptidyl carrier protein (PCP) and condensation (C) domains) which when grouped together are referred to as a single module (By similarity). Each module is responsible for the recognition (via the A domain) and incorporation of a single amino acid into the growing peptide product (By similarity). Thus, an NRP synthetase is generally composed of one or more modules and can terminate in a thioesterase domain (TE) that releases the newly synthesized peptide from the enzyme (By similarity). Occasionally, methyltransferase domains (responsible for amino acid methylation) are present within the NRP synthetase (By similarity). NPS1 has the following architecture: A-T-C-T-C. Belongs to the NRP synthetase family.