Engineering the acyltransferase substrate specificity of assembly line polyketide synthases

Dunn, Briana J.; Khosla, Chaitan

doi:10.1098/rsif.2013.0297

Cited by 107 publications

(119 citation statements)

References 128 publications

(257 reference statements)

Supporting

Mentioning

114

Contrasting

Order By: Relevance

“…In modular type I PKSs, functional domains are organized into several modules, with each module being responsible Insights into biosynthetic mechanisms of polyketides only achieved considerable progress from 1953 when Birch and Donovan hypothesized a potential biosynthetic pathway similar to that of fatty acids [9]. Further advancements in the polyketide field led to the consensus that polyketides are typically biosynthesized through successive decarboxylative condensations of coenzyme A (CoA)-derived units, into a complex polycyclic multi-carbon compound containing keto or hydroxyl groups [10]. Downstream modifying enzymes are then used to obtain flavonoids and other bioactive substances.…”

Section: Introductionmentioning

confidence: 99%

Exploiting the Biosynthetic Potential of Type III Polyketide Synthases

Lim

Yew

2016

Molecules

View full text Add to dashboard Cite

Abstract:Polyketides are structurally and functionally diverse secondary metabolites that are biosynthesized by polyketide synthases (PKSs) using acyl-CoA precursors. Recent studies in the engineering and structural characterization of PKSs have facilitated the use of target enzymes as biocatalysts to produce novel functionally optimized polyketides. These compounds may serve as potential drug leads. This review summarizes the insights gained from research on type III PKSs, from the discovery of chalcone synthase in plants to novel PKSs in bacteria and fungi. To date, at least 15 families of type III PKSs have been characterized, highlighting the utility of PKSs in the development of natural product libraries for therapeutic development.

show abstract

Section: Introductionmentioning

confidence: 99%

Exploiting the Biosynthetic Potential of Type III Polyketide Synthases

Lim

Yew

2016

Molecules

View full text Add to dashboard Cite

show abstract

“…Some ATs were reported to recognize ACP-bound substrates such as methoxymalonyl-, hydroxymalonyl-, and aminomalonyl-ACP (3,4). Thus, ATs are key determinants of building block specificity in polyketide biosynthesis and attractive targets to change the substrate specificity to obtain biologically active unnatural polyketide products (5). However, the substitution of an AT domain by a homologous AT domain possessing different substrate specificity resulted in reduced or abolished production of polyketide analogs in many cases, probably because of disruption of proper protein-protein interactions or the inability of downstream modules to process polyketide analogs (5,6).…”

mentioning

confidence: 99%

Structure-based analysis of the molecular interactions between acyltransferase and acyl carrier protein in vicenistatin biosynthesis

Miyanaga

Iwasawa

Shinohara

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Acyltransferases (ATs) are key determinants of building block specificity in polyketide biosynthesis. Despite the importance of protein-protein interactions between AT and acyl carrier protein (ACP) during the acyltransfer reaction, the mechanism of ACP recognition by AT is not understood in detail. Herein, we report the crystal structure of AT VinK, which transfers a dipeptide group between two ACPs, VinL and VinP1LdACP, in vicenistatin biosynthesis. The isolated VinK structure showed a unique substrate-binding pocket for the dipeptide group linked to ACP. To gain greater insight into the mechanism of ACP recognition, we attempted to crystallize the VinK-ACP complexes. Because transient enzyme-ACP complexes are difficult to crystallize, we developed a covalent cross-linking strategy using a bifunctional maleimide reagent to trap the VinK-ACP complexes, allowing the determination of the crystal structure of the VinK-VinL complex. In the complex structure, Arg-153, Met-206, and Arg-299 of VinK interact with the negatively charged helix II region of VinL. The VinK-VinL complex structure allows, to our knowledge, the first visualization of the interaction between AT and ACP and provides detailed mechanistic insights into ACP recognition by AT.polyketide | acyltransferase | acyl carrier protein | protein-protein interaction | cross-linking P olyketide synthases (PKSs) are multifunctional enzymes responsible for the biosynthesis of various polyketide natural products (1). Bacterial modular PKSs comprise several catalytic modules that are each responsible for a single round of the polyketide chain elongation reaction. Each module minimally consists of a ketosynthase (KS) domain, an acyltransferase (AT) domain, and an acyl carrier protein (ACP) domain. The AT domain recognizes a specific acyl building block and catalyzes its transfer reaction onto the 4′-phosphopantetheine arm of the ACP. KS extends the polyketide chain by condensing the resulting ACP-bound building blocks with the elongated acylACPs. Although standard modular PKSs contain AT domains in their modules, some modular PKSs lack AT domains in each module and instead receive their acyl building blocks by standalone trans-acting ATs (2).The selection of the starter unit is generally governed by the substrate specificity of the AT domain in the loading module (1). In some modular PKS systems, a didomain-type loading module comprising a loading AT domain and an ACP domain selects an acyl starter building block such as an acetate unit to generate an acyl-ACP intermediate, which is transferred to the downstream extension module for polyketide chain elongation. Alternatively, in a KS Q -type loading module consisting of three domains, the AT domain selects an α-carboxyacyl substrate such as a malonyl group, and the KS Q domain subsequently catalyzes its decarboxylation to construct an acyl-ACP thioester. For polyketide chain elongation, the AT domain of the extension module generally recognizes a specific α-carboxyacyl-CoA as an extender building block (3). Malony...

show abstract

“…Based on such knowledge, various strategies such as domain swap, domain hybrid, site-directed mutagenesis and trans-AT complementation that were reviewed by Dunn and Khosla [27] can be used to modify the AT domains to select an "unnatural" starter or extender unit. This review summarizes some new cases about AT domain modification in recent years.…”

Section: At Domainmentioning

confidence: 99%

The Combinatorial Biosynthesis of “Unnatural” Products with Polyketides

Zhang

Duan

et al. 2018

Trans. Tianjin Univ.

View full text Add to dashboard Cite

Polyketides have been widely used clinically due to their significant biological activities, but the needed structural and functional diversity cannot be achieved by common chemical synthetic methods. The tool of combinatorial biosynthesis provides the possibility to produce "unnatural" natural drugs, which has achieved initial success. This paper provides an overview for the strategies of combinatorial biosynthesis in producing the structural and functional diversity of polyketides, including the redesign of metabolic flow, polyketide synthase (PKS) engineering, and PKS post-translational modification. Although encouraging progress has been made in the last decade, challenges still exist regarding the rational combinatorial biosynthesis of polyketides. In this review, the perspectives of polyketide combinatorial biosynthesis are also discussed.

show abstract

Engineering the acyltransferase substrate specificity of assembly line polyketide synthases

Cited by 107 publications

References 128 publications

Exploiting the Biosynthetic Potential of Type III Polyketide Synthases

Exploiting the Biosynthetic Potential of Type III Polyketide Synthases

Structure-based analysis of the molecular interactions between acyltransferase and acyl carrier protein in vicenistatin biosynthesis

The Combinatorial Biosynthesis of “Unnatural” Products with Polyketides

Contact Info

Product

Resources

About