Water-deficit stress induces prenylated stilbenoid production and affects biomass in peanut hairy roots: Exploring the role of stilbenoid prenyltransferase downregulation.

The peanut plant is one of the most economically important crops around the world. Abiotic stress, such as drought, causes over five hundred million dollars in losses in peanut production per year. Peanuts are known to produce prenylated stilbenoids to counteract biotic stress. However, their role in abiotic stress tolerance has not been elucidated. To address this issue, hairy roots with the capacity to produce prenylated stilbenoids were established. An RNA-interference (RNAi) molecular construct targeting the stilbenoid-specific prenyltransferase AhR4DT-1 was designed and expressed via Agrobacterium rhizogenes-mediated transformation in hairy roots of peanut cultivar Georgia Green. Two transgenic hairy roots with the RNAi molecular construct were established, and the downregulation of AhR4DT-1 was validated using reverse transcriptase quantitative PCR. To determine the efficacy of the RNAi-approach in modifying the levels of prenylated stilbenoids, the hairy roots were co-treated with methyl jasmonate, hydrogen peroxide, cyclodextrin, and magnesium chloride to induce the production of stilbenoids and then the stilbenoids were analyzed in extracts of the culture medium. Highly reduced levels of prenylated stilbenoids were observed in the RNAi hairy roots. Furthermore, the hairy roots were evaluated in a polyethylene glycol (PEG) assay to assess the role of prenylated stilbenoids on water-deficit stress. Upon PEG treatment, stilbenoids were induced and secreted into the culture medium of RNAi and wild-type hairy roots. Additionally, the biomass of the RNAi hairy roots decreased by a higher amount as compared to the wild-type hairy roots suggesting that prenylated stilbenoids might play a role against water-deficit stress.

Genome Mining Reveals a UbiA-Type Prenyltransferase Access to Farnesylation of Diketopiperazines.

UbiA-type prenyltransferases (PTases) are significant enzymes that lead to structurally diverse meroterpenoids. Herein, we report the identification and characterization of an undescribed UbiA-type PTase, FtaB, that is responsible for the farnesylation of indole-containing diketopiperazines (DKPs) through genome mining. Heterologous expression of the fta gene cluster and non-native pathways result in the production of a series of new C2-farnesylated DKPs. This study broadens the reaction scope of UbiA-type PTases and expands the chemical diversity of meroterpenoids.

Biochemical characterization of a multiple prenyltransferase from Tolypocladium inflatum.

Prenylation plays a pivotal role in the diversification and biological activities of natural products. This study presents the functional characterization of TolF, a multiple prenyltransferase from Tolypocladium inflatum. The heterologous expression of tolF in Aspergillus oryzae, coupled with feeding the transformed strain with paxilline, resulted in the production of 20- and 22-prenylpaxilline. Additionally, TolF demonstrated the ability to prenylated the reduced form of paxilline, ß-paxitriol. A related prenyltransferase TerF from Chaunopycnis alba, exhibited similar substrate tolerance and regioselectivity. In vitro enzyme assays using purified recombinant enzymes TolF and TerF confirmed their capacity to catalyze prenylation of paxilline, ß-paxitriol, and terpendole I. Based on previous reports, terpendole I should be considered a native substrate. This work not only enhances our understanding of the molecular basis and product diversity of prenylation reactions in indole diterpene biosynthesis, but also provides insights into the potential of fungal indole diterpene prenyltransferase to alter their position specificities for prenylation. This could be applicable for the synthesis of industrially useful compounds, including bioactive compounds, thereby opening up new avenues for the development of novel biosynthetic strategies and pharmaceuticals. KEY POINTS: • The study characterizes TolF as a multiple prenyltransferase from Tolypocladium inflatum. • TerF from Chaunopycnis alba shows similar substrate tolerance and regioselectivity compared to TolF. • The research offers insights into the potential applications of fungal indole diterpene prenyltransferases.

Enzymatic properties and immobilization of a thermostable prenyltransferase from Aspergillus fumigatiaffinis for the production of prenylated naringenin.

Prenyltransferases catalyze the synthesis of prenylated flavonoids, providing these with greater lipid solubility, biological activity, and availability. In this study, a thermostable prenyltransferase (AfPT) from Aspergillus fumigatiaffinis was cloned and expressed in Escherichia coli. By optimizing induction conditions, the expression level of AfPT reached 39.3 mU/mL, which was approximately 200 % of that before optimization. Additionally, we determined the enzymatic properties of AfPT. Subsequently, AfPT was immobilized on carboxymethyl cellulose magnetic nanoparticles (CMN) at a maximum load of 0.6 mg/mg. Optimal activity of CMN-AfPT was achieved at pH 8.0 and 55 °C. Thermostability assays showed that the residual activity of CMN-AfPT was greater than 50 % after incubation at 55 °C for 4 h. Km and Vmax of CMN-AfPT for naringenin were 0.082 mM and 5.57 nmol/min/mg, respectively. The Kcat/Km ratio of CMN-AfPT was higher than that of AfPT. Residual prenyltransferase activity of CMN-AfPT remained higher than 70 % even after 30 days of storage. Further, CMN-AfPT retained 68 % of its original activity after 10 cycles of reuse. Compared with free AfPT, CMN-AfPT showed higher catalytic efficiency, thermostability, metal ion tolerance, substrate affinity, storage stability, and reusability. Our study presents a thermostable prenyltransferase and its immobilized form for the production of prenylated flavonoids in vitro.

Substrate-Dependent Alteration in the C- and O-Prenylation Specificities of Cannabis Prenyltransferase.

CsPT4 is an aromatic prenyltransferase that synthesizes cannabigerolic acid (CBGA), the key intermediate of cannabinoid biosynthesis in Cannabis sativa, from olivetolic acid (OA) and geranyl diphosphate (GPP). CsPT4 has a catalytic potential to produce a variety of CBGA analogs via regioselective C-prenylation of aromatic substrates having resorcylic acid skeletons including bibenzyl 2,4-dihydroxy-6-phenylethylbenzoic acid (DPA). In this study, we further investigated the substrate specificity of CsPT4 using phlorocaprophenone (PCP) and 2',4',6'-trihydroxydihydrochalcone (THDC), the isomers of OA and DPA, respectively, and demonstrated that CsPT4 catalyzed both C-prenylation and O-prenylation reactions on PCP and THDC that share acylphloroglucinol substructures. Interestingly, the kinetic parameters of CsPT4 for these substrates differed depending on whether they underwent C-prenylation or O-prenylation, suggesting that this enzyme utilized different substrate-binding modes suitable for the respective reactions. Aromatic prenyltransferases that catalyze O-prenylation are rare in the plant kingdom, and CsPT4 was notable for altering the reaction specificity between C- and O-prenylations depending on the skeletons of aromatic substrates. We also demonstrated that enzymatically synthesized geranylated acylphloroglucinols had potent antiausterity activity against PANC-1 human pancreatic cancer cells, with 4'-O-geranyl THDC being the most effective. We suggest that CsPT4 is a valuable catalyst to generate biologically active C- and O-prenylated molecules that could be anticancer lead compounds.

Vitamin K converting enzyme UBIAD1 plays an important role in osteogenesis and chondrogenesis in mice.

Dietary vitamin K1 (phylloquinone: PK) and menaquinone (MK-n) are converted to menadione (MD) in the small intestine and then translocated to various tissues where they are converted to vitamin K2 (menaquinone-4: MK-4) by UbiA prenyltransferase domain containing protein 1 (UBIAD1). MK-4 is effective in bone formation and is used to treat osteoporosis in Japan. UBIAD1 is expressed in bone and osteoblasts and shows conversion to MK-4, but the role of UBIAD1 in osteogenesis is unknown. In this study, we investigated the function of UBIAD1 in osteogenesis using a tamoxifen-dependent UBIAD1-deficient mouse model. When UBIAD1 deficiency was induced from the first week of life, the femur was significantly shortened, and bone mineral density (BMD) was reduced. In addition, the expression of bone and chondrocyte matrix proteins and chondrocyte differentiation factors was significantly decreased. In primary cultured chondrocytes, chondrocyte differentiation was significantly reduced by UBIAD1 deficiency. These results suggest that UBIAD1 is an important factor for the regulation of chondrocyte proliferation and differentiation during osteogenesis.

Parallel Evolution of Asco- and Basidiomycete O-Prenyltransferases.

Prenyltransferases (PTs) are involved in the biosynthesis of a multitude of pharmaceutically and agriculturally important plant, bacterial, and fungal compounds. Although numerous prenylated compounds have been isolated from Basidiomycota (mushroom-forming fungi), knowledge of the PTs catalyzing the transfer reactions in this group of fungi is scarce. Here, we report the biochemical characterization of an O- and C-prenylating dimethylallyltryptophan synthase (DMATS)-like enzyme LpTyrPT from the scurfy deceiver Laccaria proxima. This PT transfers dimethylallyl moieties to l-tyrosine at the para-O position and to l-tryptophan at atom C-7 and represents the first basidiomycete l-tyrosine PT described so far. Phylogenetic analysis of PTs in fungi revealed that basidiomycete l-tyrosine PTs have evolved independently from their ascomycete counterparts and might represent the evolutionary origin of PTs acting on phenolic compounds in secondary metabolism.

Foldseek reveals a CBGA prenylating enzyme GlyMa_02G168000 from Glycine max.

The present research provides an application for an aromatic prenyltransferase from Glycine max for use in heterologous microorganism expression to generate cannabinoids. The known cannabinoid prenyltransferase CsPT04 was queried in FoldSeek. An enzyme derived from Glycine max known as GLYMA_02G168000, which is a predicted homogentisate solanyltransferase, was identified and found to have affinity for the prenylation of geranyldiphosphate (GPP) and olivetolic acid (OA) to produce cannabigerolic acid (CBGA) and cannabigerol (CBG). The in vitro production of CBGA was accomplished through the heterologous expression of this prenyltransferase in Saccharomyces cerevisiae. After growing the yeast cells, a purified microsomal fraction was harvested, which was rich in the membrane-bound prenyltransferase GlyMa_02G168000. Addition of purified microsomal fraction to a reaction matrix facilitated the successful prenylation of externally supplied OA with GPP, culminating in the production of CBGA. Structural comparisons revealed a notably closer similarity between GLYMA_02G168000 and CsPT04, compared to the similarity of other cannabinoid prenyltransferases with CsPT04. Herein, a novel application for a homogentisate solanyltransferase has been established towards the production of cannabinoids.

Structure Prediction and Genome Mining-Aided Discovery of the Bacterial C-Terminal Tryptophan Prenyltransferase PalQ.

Post-translational prenylations, found in eukaryotic primary metabolites and bacterial secondary metabolites, play crucial roles in biomolecular interactions. Employing genome mining methods combined with AlphaFold2-based predictions of protein interactions, PalQ , a prenyltransferase responsible for the tryptophan prenylation of RiPPs produced by Paenibacillus alvei, is identified. PalQ differs from cyanobactin prenyltransferases because of its evolutionary relationship to isoprene synthases, which enables PalQ to transfer extended prenyl chains to the indole C3 position. This prenylation introduces structural diversity to the tryptophan side chain and also leads to conformational dynamics in the peptide backbone, attributed to the cis/trans isomerization that arises from the formation of a pyrrolidine ring. Additionally, PalQ exhibited pronounced positional selectivity for the C-terminal tryptophan. Such enzymatic characteristics offer a toolkit for peptide therapeutic lipidation.

Geranyl diphosphate synthase large subunits OfLSU1/2 interact with small subunit OfSSUII and are involved in aromatic monoterpenes production in Osmanthus fragrans.

Osmanthus fragrans is a famous ornamental tree species for its pleasing floral fragrance. Monoterpenoids are the core floral volatiles of O. fragrans flowers, which have tremendous commercial value. Geranyl diphosphate synthase (GPPS) is a key enzyme that catalyzes the formation of GPP, the precursor of monoterpenoids. However, there are no reports of GPPSs in O. fragrans. Here, we performed RNA sequencing on the O. fragrans flowers and identified three GPPSs. Phylogenetic tree analysis showed that OfLSU1/2 belonged to the GPPS.LSU branch, while the OfSSUII belonged to the GPPS.SSU branch. OfLSU1, OfLSU2 and OfSSUII were all localized in chloroplasts. Y2H and pull-down assays showed that OfLSU1 or OfLSU2 interacted with OfSSUII to form heteromeric GPPSs. Site mutation experiments revealed that the conserved CXXXC motifs of OfLSU1/2 and OfSSUII were essential for the interaction between OfLSU1/2 and OfSSUII. Transient expression experiments showed that OfLSU1, OfLSU2 and OfSSUII co-expressed with monoterpene synthase genes OfTPS1 or OfTPS2 improved the biosynthesis of monoterpenoids (E)-ß-ocimene and linalool. The heteromeric GPPSs formed by OfLSU1/2 interacting with OfSSUII further improves the biosynthesis of monoterpenoids. Overall, these preliminary results suggested that the GPPSs play a key role in regulating the production of aromatic monoterpenes in O. fragrans.

Biosynthesis of Cosmosporasides Reveals the Assembly Line for Fungal Hybrid Terpenoid Saccharides.

Fungal hybrid terpenoid saccharides constitute a new and growing family of natural products with significant biomedical and agricultural activities. One representative family is the cosmosporasides, which feature oxidized terpenoid units and saccharide moieties; however, the assembly line of these building blocks has been elusive. Herein, a cos cluster from Fusarium orthoceras was discovered for the synthesis of cosmosporaside C (1) by genome mining. A UbiA family intramembrane prenyltransferase (UbiA-type PT), a multifunctional cytochrome P450, an α,ß-hydrolase, an acetyltransferase, a dimethylallyl transferase (DMAT-type PT) and a glycosyltransferase function cooperatively in the assembly of the scaffold of 1 using primary central metabolites. The absolute configuration at C4, C6 and C7 of 1 was also established. Our work clarifies the unexpected functions of UbiA-type and DMAT-type PTs and provides an example for understanding the synthetic logic of hybrid terpenoid saccharides in fungi.

Prenyltransferase gene expression reveals an essential role of prenylation for the inflammatory response in human gingival fibroblasts.

BACKGROUND: Prenyltrasferases (PTases) are a class of enzymes known to be responsible for promoting posttranslational modification at the carboxyl terminus of proteins containing a so-called CaaX-motif. The process is responsible for proper membrane localization and the appropriate function of several intracellular signaling proteins. Current research demonstrating the pathomechanistic importance of prenylation in inflammatory illnesses emphasizes the requirement to ascertain the differential expression of PT genes under inflammatory settings, particularly in periodontal disease. METHODS: Telomerase-immortalized human gingival fibroblasts (HGF-hTert) were cultured and treated with either inhibitors of prenylation (PTI) lonafarnib, tipifarnib, zoledronic acid, or atorvastatin at concentrations of 10 µM in combination with or without 10 µg Porphyromonas gingivalis lipopolysaccharide (LPS) for 24 h. Prenyltransferase genes FNTB, FNTA, PGGT1B, RABGGTA, RABGGTB, and PTAR1 as well as inflammatory marker genes MMP1 and IL1B were detected using quantitative real-time polymerase chain reaction (RT-qPCR). Immunoblot and protein immunoassay were used to confirm the results on the protein level. RESULTS: RT-qPCR experiments revealed significant upregulation of IL1B, MMP1, FNTA, and PGGT1B upon LPS treatment. PTase inhibitors caused significant downregulation of the inflammatory cytokine expression. Interestingly, FNTB expression was significantly upregulated in response to any PTase inhibitor in combination with LPS, but not upon LPS treatment only, indicating a vital role of protein farnesyltransferase in the proinflammatory signaling cascade. CONCLUSIONS: In this study, distinct PTase gene expression patterns in pro-inflammatory signaling were discovered. Moreover, PTase inhibiting drugs ameliorated inflammatory mediator expression by a significant margin, indicating that prenylation is a major pre-requisite for innate immunity in periodontal cells.

A basidomycetous hydroxynaphthalene-prenylating enzyme exhibits promiscuity toward prenyl donors.

The fungal prenyltransferase ShPT from Stereum hirsutum was believed to prenylate 4-hydroxybenzyl alcohol and thereby be involved in the vibralactone biosynthesis. In this study, we demonstrate that hydroxynaphthalenes instead of benzyl alcohol or aldehyde were accepted by ShPT for regular C-prenylation in the presence of both dimethylallyl and geranyl diphosphate. Although the natural substrate of ShPT remains unknown, our results provide one additional prenyltransferase from basidiomycetes, which are less studied, in comparison to those from other sources. Furthermore, this study expands the chemical toolbox for regioselective production of prenylated naphthalene derivatives. KEY POINTS: •Basidiomycetous prenyltransferase •Biochemical characterization •A DMATS prenyltransferase prenylating hydroxynaphthalene derivatives.

Regulation of protein prenylation.

Prenyltransferases (PTases) are known to play a role in embryonic development, normal tissue homeostasis and cancer by posttranslationally modifying proteins involved in these processes. They are being discussed as potential drug targets in an increasing number of diseases, ranging from Alzheimer's disease to malaria. Protein prenylation and the development of specific PTase inhibitors (PTIs) have been subject to intense research in recent decades. Recently, the FDA approved lonafarnib, a specific farnesyltransferase inhibitor that acts directly on protein prenylation; and bempedoic acid, an ATP citrate lyase inhibitor that might alter intracellular isoprenoid composition, the relative concentrations of which can exert a decisive influence on protein prenylation. Both drugs represent the first approved agent in their respective substance class. Furthermore, an overwhelming number of processes and proteins that regulate protein prenylation have been identified over the years, many of which have been proposed as molecular targets for pharmacotherapy in their own right. However, certain aspects of protein prenylation, such as the regulation of PTase gene expression or the modulation of PTase activity by phosphorylation, have attracted less attention, despite their reported influence on tumor cell proliferation. Here, we want to summarize the advances regarding our understanding of the regulation of protein prenylation and the potential implications for drug development. Additionally, we want to suggest new lines of investigation that encompass the search for regulatory elements for PTases, especially at the genetic and epigenetic levels.

Biosynthesis of polyprenylated xanthones in Hypericum perforatum roots involves 4-prenyltransferase.

Polyprenylated xanthones are natural products with a multitude of biological and pharmacological activities. However, their biosynthetic pathway is not completely understood. In this study, metabolic profiling revealed the presence of 4-prenylated 1,3,5,6-tetrahydroxyxanthone derivatives in St. John's wort (Hypericum perforatum) root extracts. Transcriptomic data mining led to the detection of 5 variants of xanthone 4-prenyltransferase (HpPT4px) comprising 4 long variants (HpPT4px-v1 to HpPT4px-v4) and 1 short variant (HpPT4px-sh). The full-length sequences of all 5 variants were cloned and heterologously expressed in yeast (Saccharomyces cerevisiae). Microsomes containing HpPT4px-v2, HpPT4px-v4, and HpPT4px-sh catalyzed the addition of a prenyl group at the C-4 position of 1,3,5,6-tetrahydroxyxanthone; 1,3,5-trihydroxyxanthone; and 1,3,7-trihydroxyxanthone, whereas microsomes harboring HpPT4px-v1 and HpPT4px-v3 additionally accepted 1,3,6,7-tetrahydroxyxanthone. HpPT4px-v1 produced in Nicotiana benthamiana displayed the same activity as in yeast, while HpPT4px-sh was inactive. The kinetic parameters of HpPT4px-v1 and HpPT4px-sh chosen as representative variants indicated 1,3,5,6-tetrahydroxyxanthone as the preferred acceptor substrate, rationalizing that HpPT4px catalyzes the first prenylation step in the biosynthesis of polyprenylated xanthones in H. perforatum. Dimethylallyl pyrophosphate was the exclusive prenyl donor. Expression of the HpPT4px transcripts was highest in roots and leaves, raising the question of product translocation. C-terminal yellow fluorescent protein fusion of HpPT4px-v1 localized to the envelope of chloroplasts in N. benthamiana leaves, whereas short, truncated, and masked signal peptides led to the disruption of plastidial localization. These findings pave the way for a better understanding of the prenylation of xanthones in plants and the identification of additional xanthone-specific prenyltransferases.

The functional evolution of architecturally different plant geranyl diphosphate synthases from geranylgeranyl diphosphate synthase.

Terpenoids constitute the largest class of plant primary and secondary metabolites with a broad range of biological and ecological functions. They are synthesized from isopentenyl diphosphate and dimethylallyl diphosphate, which in plastids are condensed by geranylgeranyl diphosphate synthases (GGPPSs) to produce GGPP (C20) for diterpene biosynthesis and by geranyl diphosphate synthases (GPPSs) to form GPP (C10) for monoterpene production. Depending on the plant species, unlike homomeric GGPPSs, GPPSs exist as homo- and heteromers, the latter of which contain catalytically inactive GGPPS-homologous small subunits (SSUs) that can interact with GGPPSs. By combining phylogenetic analysis with functional characterization of GGPPS homologs from a wide range of photosynthetic organisms, we investigated how different GPPS architectures have evolved within the GGPPS protein family. Our results reveal that GGPPS gene family expansion and functional divergence began early in nonvascular plants, and that independent parallel evolutionary processes gave rise to homomeric and heteromeric GPPSs. By site-directed mutagenesis and molecular dynamics simulations, we also discovered that Leu-Val/Val-Ala pairs of amino acid residues were pivotal in the functional divergence of homomeric GPPSs and GGPPSs. Overall, our study elucidated an evolutionary path for the formation of GPPSs with different architectures from GGPPSs and uncovered the molecular mechanisms involved in this differentiation.

Chemoenzymatic Late-Stage Modifications Enable Downstream Click-Mediated Fluorescent Tagging of Peptides.

Aromatic prenyltransferases from cyanobactin biosynthetic pathways catalyse the chemoselective and regioselective intramolecular transfer of prenyl/geranyl groups from isoprene donors to an electron-rich position in these macrocyclic and linear peptides. These enzymes often demonstrate relaxed substrate specificity and are considered useful biocatalysts for structural diversification of peptides. Herein, we assess the isoprene donor specificity of the N1-tryptophan prenyltransferase AcyF from the anacyclamide A8P pathway using a library of 22 synthetic alkyl pyrophosphate analogues, of which many display reactive groups that are amenable to additional functionalization. We further used AcyF to introduce a reactive moiety into a tryptophan-containing cyclic peptide and subsequently used click chemistry to fluorescently label the enzymatically modified peptide. This chemoenzymatic strategy allows late-stage modification of peptides and is useful for many applications.

Heteromerization of short-chain trans-prenyltransferase controls precursor allocation within a plastidial terpenoid network.

Terpenes are the largest and most diverse class of plant specialized metabolites. Sesterterpenes (C25), which are derived from the plastid methylerythritol phosphate pathway, were recently characterized in plants. In Arabidopsis thaliana, four genes encoding geranylfarnesyl diphosphate synthase (GFPPS) (AtGFPPS1 to 4) are responsible for the production of GFPP, which is the common precursor for sesterterpene biosynthesis. However, the interplay between sesterterpenes and other known terpenes remain elusive. Here, we first provide genetic evidence to demonstrate that GFPPSs are responsible for sesterterpene production in Arabidopsis. Blockage of the sesterterpene pathway at the GFPPS step increased the production of geranylgeranyl diphosphate (GGPP)-derived terpenes. Interestingly, co-expression of sesterTPSs in GFPPS-OE (overexpression) plants rescued the phenotypic changes of GFPPS-OE plants by restoring the endogenous GGPP. We further demonstrated that, in addition to precursor (DMAPP/IPP) competition by GFPPS and GGPP synthase (GGPPS) in plastids, GFPPS directly decreased the activity of GGPPS through protein-protein interaction, ultimately leading to GGPP deficiency in planta. Our study provides a new regulatory mechanism of the plastidial terpenoid network in plant cells.

Switching Prenyl Donor Specificities in Squalene Synthase-Like Aromatic Prenyltransferases from Bacterial Carbazole Alkaloid Biosynthesis.

Lavanduquinocin (LDQ) is a potent neuroprotective carbazole alkaloid from Streptomyces species that features a rare cyclic monoterpene/cyclolavandulyl moiety attached to the tricyclic carbazole nucleus. We elucidated the biosynthetic logic of LDQ by enzymatically reconstituting the total biosynthetic pathway and identified the genes required for generating the cyclolavandulyl moiety in LDQ based on mutagenetic analysis, including a cyclolavandulyl diphosphate synthase gene ldqA and a squalene synthase-like aromatic prenyltransferase gene ldqG. LdqG is homologous to carbazole prenyltransferases, NzsG and CqsB4, discovered from the biosynthetic pathways of two bacterial carbazoles, neocarazostatin and carquinostatin. Based on analysis of the sequences and modeled protein structures, further in vitro and in vivo site-directed mutagenetic analyses led to identification of two residue sites, F53 and C57 in NzsG vs I54 and A58 in LdqG, which play crucial roles in governing the prenyl donor specificities toward cyclolavandulyl, dimethylallyl, and geranyl diphosphates. By applying this knowledge in strain engineering, prenyl donor delivery was rationally switched to produce the desired prenylated carbazoles. The study provides an opportunity to rationally manipulate the prenylation modification to carbazole alkaloids, which could influence the biological activities by increasing the affinity for membranes as well as the interactions with cellular targets.

Prenylation: A Critical Step for Biomanufacturing of Prenylated Aromatic Natural Products.

Prenylated aromatic natural products (PANPs) have received much attention due to their biomedical benefits for human health. The prenylation of aromatic natural products (ANPs), which is mainly catalyzed by aromatic prenyltransferases (aPTs), contributes significantly to their structural and functional diversity by providing higher lipophilicity and enhanced bioactivity. aPTs are widely distributed in bacteria, fungi, animals, and plants and play a key role in the regiospecific prenylation of ANPs. Recent studies have greatly advanced our understanding of the characteristics and application of aPTs. In this review, we comment on research progress regarding sources, evolutionary relationships, structural features, reaction mechanism, engineering modification, and application of aPTs. Particular emphasis is also placed on recent advances, challenges, and prospects about applications of aPTs in microbial cell factories for producing PANPs. Generally, this review could provide guidance for using aPTs as robust biocatalytic tools to produce various PANPs with high efficiency.