What is PKS pathway?
Polyketide synthases (PKSs) are a family of multi-domain enzymes or enzyme complexes that produce polyketides, a large class of secondary metabolites, in bacteria, fungi, plants, and a few animal lineages. The PKS genes for a certain polyketide are usually organized in one operon or in gene clusters.
What is polyketide pathway?
Polyketide synthases are multi-domain enzymes that catalyse the construction of many bioactive natural products. All polyketides are assembled via the repeated decarboxylative thio-Claisen condensation between malonyl-coenzyme A (malonyl-CoA) derivatives catalysed by enzyme machinery called polyketide synthases (PKSs).
How do polyketide synthases work?
Polyketide synthases (PKSs) assemble activated carboxylic acids to elaborate chemical compounds (1). Since this reaction sequence can be repeated, with each elongation varying in accessory catalytic functions, polyketides can be rich in chemistry (Fig.
What are polyketide antibiotics?
Examples of polyketides include: Macrolides; Pikromycin, the first isolated macrolide; the antibiotics erythromycin A; clarithromycin, and azithromycin; the immunosuppressant tacrolimus; Radicicol and Pochonin family (HSP90 inhibitor); Polyene antibiotics; Amphotericin; Tetracyclines and the tetracycline family of …
What is polyketides function?
Many polyketides are clinically important, with antimicrobial, anticancer and immunosuppressive properties. Moreover, they are important in the producing organisms, facilitating competition for substrates and communication between organisms (Khosla, 2009).
What is polyketide biosynthesis?
Polyketides are produced by polyketide synthases. The core biosynthesis involves stepwise condensation of a starter unit (typically acetyl-CoA or propionyl-CoA) with an extender unit (either malonyl-CoA or methylmalonyl-CoA).
What is a Ketide?
Filters. (organic chemistry) Any organic compound containing adjacent methylene and carbonyl functional groups.
What category of macromolecules are polyketides?
They are broadly divided into three classes: type I polyketides (often macrolides produced by multimodular megasynthases), type II polyketides (often aromatic molecules produced by the iterative action of dissociated enzymes), and type III polyketides (often small aromatic molecules produced by fungal species).
What is the importance of polyketide pathway in drug discovery?
In terms of biological profile, spirotetronate polyketides exhibit potent antibacterial and antitumor activities and a documented value as tools in the elucidation of new biological pathways. As such, they represent highly promising leads in drug discovery.
How are polyketides made?
Polyketides are a diverse class of compounds that are often created by a series of modular enzymes which condense and then modify chains of acetate or propionate units primarily through reduction, dehydration, cyclization, and aromatization reactions.
How many types of polyketide synthases are expressed in the nature?
Biosynthesis of polyketides involves a group of enzyme activities called polyketide synthases (PKSs). There are three types of PKSs (type I, type II, and type III) in Streptomyces responsible for producing polyketides.
What are aromatic polyketides?
Aromatic polyketides are polycyclic compounds harboring at least one aromatic ring [17]. They are an important type of natural products with antibacterial, anticancer and antiviral bioactivities, with representative examples being the above-mentioned drugs tetracyclines and anthracyclines [3, 4].