Open AccessSpecificity of Nonribosomal Peptide Synthetases in the Biosynthesis of the Pseudomonas virulence factor
Author(s) -
Gina L. Morgan,
Ashley M Kretsch,
Kevin C. Santa Maria,
Savannah J. Weeks,
Бо Ли
Publication year - 2019
Publication title -
biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.43
H-Index - 253
eISSN - 1520-4995
pISSN - 0006-2960
DOI - 10.1021/acs.biochem.9b00360
Subject(s) - nonribosomal peptide , adenylylation , virulence , amino acid , biochemistry , operon , biosynthesis , pseudomonas , biology , peptide , virulence factor , active site , residue (chemistry) , chemistry , enzyme , bacteria , gene , mutant , genetics
The Pseudomonas virulence factor ( pvf ) biosynthetic operon has been implicated in bacterial virulence and signaling. We identified 308 bacterial strains containing pvf homologues that likely produce signaling molecules with distinct structures and biological activities. Several homologues of the nonribosomal peptide synthetase (NRPS), PvfC, were biochemically characterized and shown to activate l-Val or l-Leu. The amino acid selectivity of PvfC and its homologues likely direct pvf signaling activity. We explored the natural diversity of the active site residues present in 92% of the adenylation domains of PvfC homologues and identified key residues for substrate selection and catalysis. Sequence similarity network (SSN) analysis revealed grouping of PvfC homologues that harbor the same active site residues and activate the same amino acids. Our work identified PvfC as a gatekeeper for the structure and bioactivity of the pvf -produced signaling molecules. The combination of active site residue identification and SSN analysis can improve the prediction of aliphatic amino acid substrates for NRPS adenylation domains.