TY - JOUR
T1 - Reactivity-Based Screening for Citrulline-Containing Natural Products Reveals a Family of Bacterial Peptidyl Arginine Deiminases
AU - Harris, Lonnie A.
AU - Saint-Vincent, Patricia M.B.
AU - Guo, Xiaorui
AU - Hudson, Graham A.
AU - Dicaprio, Adam J.
AU - Zhu, Lingyang
AU - Mitchell, Douglas A.
N1 - This work was supported by a grant from the National Institutes of Health (GM123998 to D.A.M.) and the Seemon Pines Fellowship from the Department of Chemistry at the University of Illinois at Urbana—Champaign (to G.A.H.). Funds to purchase the Bruker UltrafleXtreme MALDI TOF/TOF mass spectrometer were from the National Institutes of Health (S10 RR027109 A). Funds to purchase the IGB Core 600 MHz NMR were from the National Institutes of Health (S10-RR028833).
This work was supported by a grant from the National Institutes of Health (GM123998 to D.A.M.) and the Seemon Pines Fellowship from the Department of Chemistry at the University of Illinois at Urbana-Champaign (to G.A.H.). Funds to purchase the Bruker UltrafleXtreme MALDI TOF/TOF mass spectrometer were from the National Institutes of Health (S10 RR027109 A). Funds to purchase the IGB Core 600 MHz NMR were from the National Institutes of Health (S10-RR028833).
PY - 2020/12/18
Y1 - 2020/12/18
N2 - Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a family of natural products defined by a genetically encoded precursor peptide that is processed by associated biosynthetic enzymes to form the mature product. Lasso peptides are a class of RiPP defined by an isopeptide linkage between the N-terminal amine and an internal Asp/Glu residue with the C-terminal sequence threaded through the macrocycle. This unique lariat topology, which typically provides considerable stability toward heat and proteases, has stimulated interest in lasso peptides as potential therapeutics. Post-translational modifications beyond the class-defining, threaded macrolactam have been reported, including one example of Arg deimination to yield citrulline (Cit). Although a Cit-containing lasso peptide (i.e., citrulassin) was serendipitously discovered during a genome-guided campaign, the gene(s) responsible for Arg deimination has remained unknown. Herein, we describe the use of reactivity-based screening to discriminate bacterial strains that produce Arg- versus Cit-bearing citrulassins, yielding 13 new lasso peptide variants. Partial phylogenetic profiling identified a distally encoded peptidyl arginine deiminase (PAD) gene ubiquitous to the Cit-containing variants. Absence of this gene correlated strongly with lasso peptide variants only containing Arg (i.e., des-citrulassin). Heterologous expression of the PAD gene in a des-citrulassin producer resulted in the production of the deiminated analog, confirming PAD involvement in Arg deimination. The PADs were then bioinformatically surveyed to provide a deeper understanding of their taxonomic distribution and genomic contexts and to facilitate future studies that will evaluate any additional biochemical roles for the superfamily.
AB - Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a family of natural products defined by a genetically encoded precursor peptide that is processed by associated biosynthetic enzymes to form the mature product. Lasso peptides are a class of RiPP defined by an isopeptide linkage between the N-terminal amine and an internal Asp/Glu residue with the C-terminal sequence threaded through the macrocycle. This unique lariat topology, which typically provides considerable stability toward heat and proteases, has stimulated interest in lasso peptides as potential therapeutics. Post-translational modifications beyond the class-defining, threaded macrolactam have been reported, including one example of Arg deimination to yield citrulline (Cit). Although a Cit-containing lasso peptide (i.e., citrulassin) was serendipitously discovered during a genome-guided campaign, the gene(s) responsible for Arg deimination has remained unknown. Herein, we describe the use of reactivity-based screening to discriminate bacterial strains that produce Arg- versus Cit-bearing citrulassins, yielding 13 new lasso peptide variants. Partial phylogenetic profiling identified a distally encoded peptidyl arginine deiminase (PAD) gene ubiquitous to the Cit-containing variants. Absence of this gene correlated strongly with lasso peptide variants only containing Arg (i.e., des-citrulassin). Heterologous expression of the PAD gene in a des-citrulassin producer resulted in the production of the deiminated analog, confirming PAD involvement in Arg deimination. The PADs were then bioinformatically surveyed to provide a deeper understanding of their taxonomic distribution and genomic contexts and to facilitate future studies that will evaluate any additional biochemical roles for the superfamily.
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U2 - 10.1021/acschembio.0c00685
DO - 10.1021/acschembio.0c00685
M3 - Article
C2 - 33249828
AN - SCOPUS:85097737656
SN - 1554-8929
VL - 15
SP - 3167
EP - 3175
JO - ACS chemical biology
JF - ACS chemical biology
IS - 12
ER -