DCL-type Condensation domain of nonribosomal peptide synthetases (NRPSs), which catalyzes the condensation between a D-aminoacyl/peptidyl-PCP donor and a L-aminoacyl-PCP acceptor. The DCL-type Condensation (C) domain catalyzes the condensation between a D-aminoacyl/peptidyl-PCP donor and a L-aminoacyl-PCP acceptor. This domain is D-specific for the peptidyl donor and L-specific for the aminoacyl acceptor ((D)C(L)); this is in contrast with the standard LCL domains which catalyze peptide bond formation between two L-amino acids, and the restriction of ribosomes to use only L-amino acids. C domains of nonribosomal peptide synthetases (NRPSs) catalyze peptide bond formation within (usually) large multi-modular enzymatic complexes. NRPS can use a large variety of acyl monomers (approximately 500 different possible monomer substrates as opposed to the 20 standard amino acids in ribosomal protein synthesis) to construct bioactive secondary metabolites of 2 to 18 units long (with various activities such as antibiotic, antifungal, antitumor and immunosuppression). There are various subtypes of C-domains in addition to the LCL- and DCL-types such as starter C-domains which acylate the first amino acid with a beta-hydroxy carboxylic acid, and heterocyclization (Cyc) domains which catalyze both peptide bond formation and cyclization of Cys, Ser, or Thr residues. Typically, an NRPS module consists of an adenylation domain, a peptidyl carrier protein (PCP) domain (also known as thiolation (T) domain) and a C-domain. NRPS modules may also include specialized domains such as the terminal-module thioesterase (Te) domain that releases the product via hydrolysis or macrocyclization and any of various C-domain family members such as the epimerization (E) domain, the ester-bond forming C-domain, dual E/C (epimerization and condensation) domains, and the X-domain. C-domains typically have a conserved HHxxxD motif at the active site; mutations in this motif can abolish or diminish condensation activity.

similar to adenylation domain of plipastatin synthase (PpsD). This family of the adenylation (A) domain of nonribosomal peptide synthases (NRPS) includes bacitracin synthetase 1 (BacA) in Bacillus licheniformis, tyrocidine synthetase in Brevibacillus brevis, plipastatin synthase (PpsD, an important antifungal protein) in Bacillus subtilis and mannopeptimycin peptide synthetase (MppB) in Streptomyces hygroscopicus. Plipastatin has strong fungitoxic activity and is involved in inhibition of phospholipase A2 and biofilm formation. Bacitracin, a mixture of related cyclic peptides, is used as a polypeptide antibiotic while function of tyrocidine is thought to be regulation of sporulation. MppB is involved in biosynthetic pathway of mannopeptimycin, a novel class of mannosylated lipoglycopeptides. The adenylation (A) domain of NRPS recognizes a specific amino acid or hydroxy acid and activates it as an (amino) acyl adenylate by hydrolysis of ATP. The activated acyl moiety then forms a thioester bond to the enzyme-bound cofactor phosphopantetheine of a peptidyl carrier protein domain. NRPSs are large multifunctional enzymes which synthesize many therapeutically useful peptides in bacteria and fungi via a template-directed, nucleic acid independent nonribosomal mechanism. These natural products include antibiotics, immunosuppressants, plant and animal toxins, and enzyme inhibitors. NRPS has a distinct modular structure in which each module is responsible for the recognition, activation, and in some cases, modification of a single amino acid residue of the final peptide product. The modules can be subdivided into domains that catalyze specific biochemical reactions.

The adenylation domain of nonribosomal peptide synthetases (NRPS), including Bacillus subtilis termination module Surfactin (SrfA-C). The adenylation (A) domain of NRPS recognizes a specific amino acid or hydroxy acid and activates it as an (amino) acyl adenylate by hydrolysis of ATP. The activated acyl moiety then forms a thioester to the enzyme-bound cofactor phosphopantetheine of a peptidyl carrier protein domain. NRPSs are large multifunctional enzymes which synthesize many therapeutically useful peptides in bacteria and fungi via a template-directed, nucleic acid independent nonribosomal mechanism. These natural products include antibiotics, immunosuppressants, plant and animal toxins, and enzyme inhibitors. NRPS has a distinct modular structure in which each module is responsible for the recognition, activation, and, in some cases, modification of a single amino acid residue of the final peptide product. The modules can be subdivided into domains that catalyze specific biochemical reactions. This family includes the adenylation domain of the Bacillus subtilis termination module (Surfactin domain, SrfA-C) which recognizes a specific amino acid building block, which is then activated and transferred to the terminal thiol of the 4'-phosphopantetheine (Ppan) arm of the downstream peptidyl carrier protein (PCP) domain.

peptide synthase; Provisional

peptide synthase; Provisional

Crystalstructure of a 5-domain construct of LgrA in the substrate donation state [Brevibacillus parabrevis],6MG0_A Crystal structure of a 5-domain construct of LgrA in the thiolation state [Brevibacillus parabrevis],6MG0_B Crystal structure of a 5-domain construct of LgrA in the thiolation state [Brevibacillus parabrevis]

Structureof surfactin A synthetase C (SrfA-C), a nonribosomal peptide synthetase termination module [Bacillus subtilis]

Crystalstructure of dimodular LgrA in a condensation state [Brevibacillus parabrevis],6MFZ_B Crystal structure of dimodular LgrA in a condensation state [Brevibacillus parabrevis]

Structureof the apo PCP-E didomain of the gramicidin S synthetase A [Brevibacillus brevis],5ISX_A Structure of the holo PCP-E didomain of the gramicidin S synthetase A [Brevibacillus brevis],5ISX_B Structure of the holo PCP-E didomain of the gramicidin S synthetase A [Brevibacillus brevis]

Crystalstructure of a 4-domain construct of a mutant of LgrA in the substrate donation state [Brevibacillus parabrevis]

Plipastatin synthase subunit C OS=Bacillus subtilis (strain 168) OX=224308 GN=ppsC PE=1 SV=2

Linear gramicidin synthase subunit D OS=Brevibacillus parabrevis OX=54914 GN=lgrD PE=1 SV=1

Chondramide synthase cmdD OS=Chondromyces crocatus OX=52 GN=cmdD PE=1 SV=1

Linear gramicidin synthase subunit C OS=Brevibacillus parabrevis OX=54914 GN=lgrC PE=3 SV=1

Plipastatin synthase subunit A OS=Bacillus subtilis (strain 168) OX=224308 GN=ppsA PE=1 SV=2