scholarly journals Structural and bioinformatic characterization of anAcinetobacter baumanniitype II carrier protein

2014 ◽  
Vol 70 (6) ◽  
pp. 1718-1725 ◽  
Author(s):  
C. Leigh Allen ◽  
Andrew M. Gulick
Keyword(s):  
Protein Domain ◽  
Carrier Protein ◽  
Free Standing ◽  
Peptide Synthetases ◽  
Catalytic Domains ◽  
Single Protein ◽  
Domain Interactions ◽  
Partner Proteins ◽  
Precise Role

Microorganisms produce a variety of natural productsviasecondary metabolic biosynthetic pathways. Two of these types of synthetic systems, the nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), use large modular enzymes containing multiple catalytic domains in a single protein. These multidomain enzymes use an integrated carrier protein domain to transport the growing, covalently bound natural product to the neighboring catalytic domains for each step in the synthesis. Interestingly, some PKS and NRPS clusters contain free-standing domains that interact intermolecularly with other proteins. Being expressed outside the architecture of a multi-domain protein, these so-called type II proteins present challenges to understand the precise role they play. Additional structures of individual and multi-domain components of the NRPS enzymes will therefore provide a better understanding of the features that govern the domain interactions in these interesting enzyme systems. The high-resolution crystal structure of a free-standing carrier protein fromAcinetobacter baumanniithat belongs to a larger NRPS-containing operon, encoded by the ABBFA_003406–ABBFA_003399 genes ofA. baumanniistrain AB307-0294, that has been implicated inA. baumanniimotility, quorum sensing and biofilm formation, is presented here. Comparison with the closest structural homologs of other carrier proteins identifies the requirements for a conserved glycine residue and additional important sequence and structural requirements within the regions that interact with partner proteins.

Characterization of Sfp, aBacillus subtilisPhosphopantetheinyl Transferase for Peptidyl Carrier Protein Domains in Peptide Synthetases†

Biochemistry ◽  
1998 ◽  
Vol 37 (6) ◽  
pp. 1585-1595 ◽  
Author(s):  
Luis E. N. Quadri ◽  
Paul H. Weinreb ◽  
Ming Lei ◽  
Michiko M. Nakano ◽  
Peter Zuber ◽  
...  
Keyword(s):  
Protein Domains ◽  
Carrier Protein ◽  
Peptide Synthetases

scholarly journals Characterization of transglutaminase homologues found in andrimid biosynthesis

2014 ◽  
Vol 70 (a1) ◽  
pp. C476-C476
Author(s):  
Janice Reimer ◽  
T Schmeing
Keyword(s):  
Amino Acids ◽  
Polyketide Synthase ◽  
Genome Mining ◽  
Protein Domain ◽  
Amide Bond ◽  
Free Standing ◽  
Remarkable Feature ◽  
Nonribosomal Peptide ◽  
Peptide Carrier

Nonribosomal peptide synthetases (NRPSs) are multimodular enzymes that synthesize products with diverse structures and activities ranging from antibiotics to industrial solvents. They are arranged into an assembly line of modules where each module is responsible for incorporating a specific monomer into the final nonribosomal peptide (NRP). Diversity in NRPs stems from the fact that NRPSs utilize not only the 20 proteinogenic amino acids, but also include nonproteinogenic amino acids, fatty acids, and alpha-hydroxy acids as building block substrates. Andrimid is a NRP antibiotic that inhibits membrane biosynthesis by blocking bacterial acetyl coenzyme A carboxylases. It is synthesized in a hybrid NRPS-polyketide synthase (NRPS-PKS) using a fatty acid, phenylalanine, valine, and glycine. A remarkable feature of this synthetic system is that instead of a normal condensation domain, it uses two atypical free-standing proteins with homology to transglutaminases to catalyze the formation of the first and second amide bonds. We are characterizing the action of transglutaminase homologues (TGH) in andrimid synthesis using biochemical assays and X-ray crystallography. Initial investigations of the andrimid biosynthetic cluster found in Panteao agglomerans focused on the TGH, AdmF, which catalyzes the formation of the first amide bond. Crystallization trials have been initiated on AdmF in its apo form and in complex with its interacting binding partner, the peptide carrier protein domain AdmI. To date, only a few andrimid producing bacteria have been discovered. Using genome mining, a biosynthetic cluster homologous to the andrimid biosynthetic cluster found in Panteao agglomerans was identified in Vibrio coralliilyticus. The two TGHs, CoraF and CoraS, were cloned, expressed and purified, and crystallization trials are underway. Our progress in biochemical and biophysical characterization of AdmF, CoraF, and CoraS will be presented.

scholarly journals Role of the phosphopantetheinyltransferase enzyme, PswP, in the biosynthesis of antimicrobial secondary metabolites by Serratia marcescens Db10

Microbiology ◽  
2014 ◽  
Vol 160 (8) ◽  
pp. 1609-1617 ◽  
Author(s):  
Amy J. Gerc ◽  
Nicola R. Stanley-Wall ◽  
Sarah J. Coulthurst
Keyword(s):  
Secondary Metabolites ◽  
Serratia Marcescens ◽  
Protein Domain ◽  
Carrier Protein ◽  
Negative Bacterium ◽  
Peptide Synthetases ◽  
Primary And Secondary Metabolism ◽  
Fatty Acid Synthases ◽  
Bacteria And Fungi

Phosphopantetheinyltransferase (PPTase) enzymes fulfil essential roles in primary and secondary metabolism in prokaryotes, archaea and eukaryotes. PPTase enzymes catalyse the essential modification of the carrier protein domain of fatty acid synthases, polyketide synthases (PKSs) and non-ribosomal peptide synthetases (NRPSs). In bacteria and fungi, NRPS and PKS enzymes are often responsible for the biosynthesis of secondary metabolites with clinically relevant properties; these secondary metabolites include a variety of antimicrobial peptides. We have previously shown that in the Gram-negative bacterium Serratia marcescens Db10, the PPTase enzyme PswP is essential for the biosynthesis of an NRPS-PKS dependent antibiotic called althiomycin. In this work we utilize bioinformatic analyses to classify PswP as belonging to the F/KES subfamily of Sfp type PPTases and to putatively identify additional NRPS substrates of PswP, in addition to the althiomycin NRPS-PKS, in Ser . marcescens Db10. We show that PswP is required for the production of three diffusible metabolites by this organism, each possessing antimicrobial activity against Staphylococcus aureus. Genetic analyses identify the three metabolites as althiomycin, serrawettin W2 and an as-yet-uncharacterized siderophore, which may be related to enterobactin. Our results highlight the use of an individual PPTase enzyme in multiple biosynthetic pathways, each contributing to the ability of Ser. marcescens to inhibit competitor bacteria by the production of antimicrobial secondary metabolites.

scholarly journals The inherent flexibility of type I non-ribosomal peptide synthetase multienzymes drives their catalytic activities

Open Biology ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 200386
Author(s):  
Sarah Bonhomme ◽  
Andréa Dessen ◽  
Pauline Macheboeuf
Keyword(s):  
Protein Domains ◽  
Bioactive Metabolites ◽  
Carrier Protein ◽  
Type I ◽  
Peptide Synthetases ◽  
Catalytic Domains ◽  
Large Size ◽  
Peptide Synthetase ◽  
Modify Amino Acid ◽  
Conformational Rearrangements

Non-ribosomal peptide synthetases (NRPSs) are multienzymes that produce complex natural metabolites with many applications in medicine and agriculture. They are composed of numerous catalytic domains that elongate and chemically modify amino acid substrates or derivatives and of non-catalytic carrier protein domains that can tether and shuttle the growing products to the different catalytic domains. The intrinsic flexibility of NRPSs permits conformational rearrangements that are required to allow interactions between catalytic and carrier protein domains. Their large size coupled to this flexibility renders these multi-domain proteins very challenging for structural characterization. Here, we summarize recent studies that offer structural views of multi-domain NRPSs in various catalytically relevant conformations, thus providing an increased comprehension of their catalytic cycle. A better structural understanding of these multienzymes provides novel perspectives for their re-engineering to synthesize new bioactive metabolites.

Sign in / Sign up

Export Citation Format

Share Document