Biology subjects

Warzecha, H.

Publications and source records attributed to Warzecha, H..

4 recordsLinked to original sources

bioRxiv2025

Efficient accumulation of new irregular monoterpene malonyl glucosides in Nicotiana benthamiana achieved by co-expression of isoprenyl diphosphate synthases and substrate-producing enzymes

Irregular monoterpenes have limited natural sources but possess unique activities applicable in medicine and agriculture. To enable sustainable plant-based production of these compounds, we established a transient expression procedure to enhance the biosynthetic flux in Nicotiana benthamiana toward dimethylallyl diphosphate (DMAPP), a substrate for isopentenyl diphosphate synthases (IDSs) that generate irregular monoterpene skeletons. Considering the benefits of glycosylation for accumulating and storing monoterpenes in extractable form, we focused on developing a platform for production of non-volatile glycosylated irregular monoterpenes using three IDS that form branched and cyclic structures. The analysis of methanolic leaf extracts from transiently transformed N. benthamiana plants revealed six major new components, 6-O-malonyl-{beta}-D-glucopyranoside and 6-O-malonyl-{beta}-D-glucopyranosyl-(1[->]2)-{beta}-D-glucopyranoside derivatives of chrysanthemol, lavandulol and cyclolavandulol, five of which are novel compounds. Alleviating two bottlenecks in the DMAPP formation in plastids by co-expressing 1-deoxyxylulose 5-phosphate synthase and isopentenyl diphosphate isomerases increased the yield of chrysantemyl and lavandulyl glucosides produced by plant-derived IDS to 1.7 {+/-} 0.4 mol g-1 FW and 1.4 {+/-} 0.3 mol g-1 FW, respectively. A bacterial cyclolavandulyl diphosphate synthase operated efficiently in chloroplasts and cytoplasm. The highest irregular monoterpene concentrations were achieved in cytoplasm by co-expression of hydroxymethylglutaryl-CoA reductase, the bottleneck enzyme of the mevalonate pathway for DMAPP biosynthesis. The mean level of cyclolavandulyl glucosides reached 3.9 {+/-} 1.5 mol g-1 FW; the top-performing plants contained 6.6 mol g-1 FW. This yield represents the highest amount of irregular monoterpene glycosides produced in plant systems.

plant biology↗

bioRxiv2023

Nepeta cataria L. (catnip) can serve as a chassis for the engineering of secondary metabolic pathways.

ObjectiveEvaluation of Nepeta cataria as a host with specific endogenous metabolite background for transient expression and metabolic engineering of secondary biosynthetic sequences. ResultsThe reporter gene GFP::licBM3 as well as three biosynthetic genes leading to the formation of the cannabinoid precursor olivetolic acid were adopted to the modular cloning standard GoldenBraid, transiently expressed in two chemotypes of N. cataria and compared to Nicotiana benthamiana. To estimate the expression efficiency in both hosts, quantification of the reporter activity was carried out with a sensitive and specific lichenase assay. While N. benthamiana exhibited lichenase activity of 676 {+/-} 94 mol g-1 s-1 (Gerasimenko et al. 2019), N. cataria cultivar 1000, and the cultivar Citriodora showed an activity of 37 {+/-} 8 mol g-1 s-1 and 18 {+/-} 4 mol g-1 s-1, respectively. Further, combinatorial expression of genes involved in cannabinoid biosynthetic pathway acylactivating enzyme 1 (aae1), olivetol synthase (ols) and olivetolic acid cyclase (oac) in N. cataria cv. resulted presumably in the in vivo production of olivetolic acid glycosides. ConclusionNepeta cataria is amenable to Agrobacterium-mediated transient expression and could serve as a novel chassis for the engineering of secondary metabolic pathways and transient evaluation of heterologous genes.

plant biology↗

bioRxiv2023

Identification and characterisation of Planococcus citri cis- and trans-isoprenyl diphosphate synthase genes, supported by short- and long-read transcriptome data

Many insect species rely on diverse terpenoids for their development and interorganismal interactions. However, little is known about terpenoid biosynthesis in insects. The monoterpenoid sex pheromones of mealybugs and scale insects (Coccoidea) are particularly enigmatic, with several species producing unique structures presumed to result from the irregular coupling activity of unidentified isopentenyl diphosphate synthases (IDSs). Enzymes capable of similar transformations have previously only been described from a few plant, bacterial and archaeal species. To investigate if insect irregular monoterpenes can be biosynthesised by similar enzymes, we performed a comprehensive search for IDS coding sequences in the genome of Planococcus citri, a widespread agricultural pest. We complemented the available P. citri genome data with newly generated short- and long-read transcriptome data. The identified candidate genes had homology to both short- and long-chain IDSs and some appeared to be paralogous, indicating gene duplications and consequent IDS gene family expansion in P. citri. We tested the activity of eleven candidate gene products, confirming in vitro regular activity for five enzymes, one of which (transIDS5) also produced the irregular prenyl diphosphates, maconelliyl and lavandulyl diphosphate. Targeted mutagenesis of selected aspartates and a lysine in the active site of transIDS5 uncovered their importance for chain-length preference and irregular coupling. This work provides an important foundation for deciphering terpenoid biosynthesis in mealybugs, as well as a potential source of enzymes for the biotechnological production of sustainable insect pest management products.

biochemistry↗

bioRxiv2018

Engineering of new-to-nature halogenated indigo precursors in plants

Plants are versatile chemists producing a tremendous variety of specialized compounds. Here, we describe the engineering of entirely novel metabolic pathways in planta enabling generation of halogenated indigo precursors as non-natural plant products.\n\nIndican (indolyl-{beta}-D-glucopyranoside) is a secondary metabolite characteristic of a number of dyers plants. Its deglucosylation and subsequent oxidative dimerization leads to the blue dye, indigo. Halogenated indican derivatives are commonly used as detection reagents in histochemical and molecular biology applications; their production, however, relies largely on chemical synthesis. To attain the de novo biosynthesis in a plant-based system devoid of indican, we employed a sequence of enzymes from diverse sources, including three microbial tryptophan halogenases substituting the amino acid at either C5, C6, or C7 of the indole moiety. Subsequent processing of the halotryptophan by bacterial tryptophanase TnaA in concert with a mutant of the human cytochrome P450 monooxygenase 2A6 and glycosylation of the resulting indoxyl derivatives by an endogenous tobacco glucosyltransferase yielded corresponding haloindican variants in transiently transformed Nicotiana benthamiana plants. Accumulation levels were highest when the 5-halogenase PyrH was utilized, reaching 0.93 {+/-}0.089 mg/g dry weight of 5-chloroindican. The identity of the latter was unambiguously confirmed by NMR analysis. Moreover, our combinatorial approach, facilitated by the modular assembly capabilities of the GoldenBraid cloning system and inspired by the unique compartmentation of plant cells, afforded testing a number of alternative subcellular localizations for pathway design. In consequence, chloroplasts were validated as functional biosynthetic venues for haloindican, with the requisite reducing augmentation of the halogenases as well as the cytochrome P450 monooxygenase fulfilled by catalytic systems native to the organelle.\n\nThus, our study puts forward a viable alternative production platform for halogenated fine chemicals, eschewing reliance on fossil fuel resources and toxic chemicals. We further contend that in planta generation of halogenated indigoid precursors previously unknown to nature offers an extended view on and, indeed, pushes forward the established frontiers of biosynthetic capacity of plants.\n\nGraphical abstract\n\nHighlightsO_LIEntirely novel combinatorial pathway yielded new-to-nature halogenated indigoids.\nC_LIO_LIAn array of specific chloro- and bromoindican regioisomers was generated.\nC_LIO_LISignificant retrieval rates afforded unambiguous metabolite identification.\nC_LIO_LIEngineered plants emerge as alternative manufacture chassis for fine chemicals.\nC_LI

synthetic biology↗