The adenylation domain of the enzyme catalyses the activation of L-cysteine to (L-cysteinyl)adenylate, followed by the transfer of the activated compound to the free thiol of a phosphopantetheine arm of a peptidyl-carrier protein domain. The peptidyl-carrier protein domain may be part of the same protein, or of a different protein. This activity is often found as part of a larger non-ribosomal peptide synthase.
The enzyme appears in viruses and cellular organisms
The adenylation domain of the enzyme catalyses the activation of L-cysteine to (L-cysteinyl)adenylate, followed by the transfer of the activated compound to the free thiol of a phosphopantetheine arm of a peptidyl-carrier protein domain. The peptidyl-carrier protein domain may be part of the same protein, or of a different protein. This activity is often found as part of a larger non-ribosomal peptide synthase.
Substrates: the formation of cysteinyl-S-cysteinyl-carrier protein in PchE and PchF is an acylation in-cis, in which the cysteine transferase activity of each synthetase's adenylation domain loads cysteine on the cysteinyl-carrier protein domain located within the same polypeptide. No substrate: D-cysteine Products: -
Substrates: the formation of cysteinyl-S-cysteinyl-carrier protein in PchE and PchF is an acylation in-cis, in which the cysteine transferase activity of each synthetase's adenylation domain loads cysteine on the cysteinyl-carrier protein domain located within the same polypeptide. No substrate: D-cysteine Products: -
Substrates: the formation of cysteinyl-S-cysteinyl-carrier protein in PchE and PchF is an acylation in-cis, in which the cysteine transferase activity of each synthetase's adenylation domain loads cysteine on the cysteinyl-carrier protein domain located within the same polypeptide. No substrate: D-cysteine Products: -
Substrates: the formation of cysteinyl-S-cysteinyl-carrier protein in PchE and PchF is an acylation in-cis, in which the cysteine transferase activity of each synthetase's adenylation domain loads cysteine on the cysteinyl-carrier protein domain located within the same polypeptide. No substrate: D-cysteine Products: -
protein PchD, PchE, and PchF are involved in biogenesis of the nonribosomal peptide siderophore pyochelin. PchE and PchF activate the cysteine as adenylate. PchD, PchE, and PchF produce the tricyclic acid hydroxyphenyl-thiazolyl-thiazolinyl-carboxylic acid. The three proteins contain three adenylation domains, one specific for salicylate activation and two specific for cysteine activation, and three carrier protein domains (two in PchE and one in PchF) that undergo posttranslational priming with phosphopantetheine to enable covalent tethering of salicyl and cysteinyl moieties as acyl-S-enzyme intermediates. Two cyclization domains (Cy1 in PchE and Cy2 in PchF) create the two amide linkages in the elongating chains and the cyclodehydrations of acylcysteine moieties into thiazolinyl rings. The ninth domain, the most downstream domain in PchF, is the chain-terminating, acyl-S-enzyme thioester hydrolase that releases the hydroxyphenyl-thiazolyl-thiazolinyl-carboxylic acid-S-enzyme intermediate to the tandem bis-heterocyclic acid product
siderophore pyochelin formation is obtained in the heterologous host Escherichia coli expressing genes pchDCBA and pchEFG together with the Escherichia coli entD gene, which provides a phosphopantetheinyl transferase necessary for PchE and PchF activation. The PchG protein in combination with PchD and phosphopantetheinylated PchE and PchF in vitro produces pyochelin from salicylate, L-cysteine, ATP, NADPH, and S-adenosylmethionine
posttranslational modification by covalent attachment of the 4'-phosphopantetheine moiety of coenzyme A is essential for the biosynthetic competence. In PchE, possible domains for phosphopantetheinylation are an N-terminal aryl carrier protein domain and a C-terminal peptidyl carrier protein domain
posttranslational modification by covalent attachment of the 4'-phosphopantetheine moiety of coenzyme A is essential for the biosynthetic competence. PchF has a single carrier protein domain (PCP2), and is phosphopantetheinylated with a stoichiometry of 67%
thioesterase domain active site double mutant, fails to turn over, but a monocyclic hydroxyphenyl-thiazolinyl-cysteine product continues to be released from subunit PchE
Assembly of the Pseudomonas aeruginosa nonribosomal peptide siderophore pyochelin In vitro reconstitution of aryl-4,2-bisthiazoline synthetase activity from PchD, PchE, and PchF
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