Variation in the chemical profiles of three foxglove species in the central Balkans

Elucidation of the plant progesterone biosynthetic pathway and its application in a yeast cell factory

Progesterone and its steroidal derivatives, including androgens, estrogens, glucocorticoids and mineralocorticoids are extensively utilized in pharmacotherapy, serving as predominant agents in anti-inflammatory, contraceptive, and anticancer treatments. From the 1990s to the present, scientists attempted to biosynthesize steroids such as progesterone and hydrocortisone from sugars in engineered microbial strains expressing pathway enzymes derived from animal sources. However, the low activity of the cytochrome P450 sterol side-chain cleavage (P450scc) system and their mitochondrial compartmentalization have limited the development of this route. Therefore, discovering an efficient P450scc system and developing innovative strategies will be necessary to overcome this bottleneck. Here, we elucidated the complete biosynthetic pathway of progesterone in Marsdenia tenacissima, a medicinal plant rich in steroids. The pathway comprises four enzymes, the two P450scc enzymes MtCYP108 and MtCYP150, as well as the two 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerases (HSDs) MtHSD5 and MtHSD6. Unlike their animal counterparts, the plant-derived P450scc enzymes were found to be localized to the endoplasmic reticulum in yeast and plants, and using the plant-type cytochrome P450 reductase (CPR) as electron transfer chain. The plant-derived HSDs are cytoplasmic in yeast and plants, whereas animal-derived HSDs localize to the endoplasmic reticulum. Based on this discovery, we engineered a yeast-based cell factory capable of synthesizing 1.06 g/L of progesterone from a simple carbon source. This discovery lays the groundwork for the sustainable synthesis of steroid hormone drugs through the use of plant-based systems or microbial host cells.

Drugs from poisonous plants: Ethnopharmacological relevance to modern perspectives

The world of plant diversity is endlessly fascinating and essential for life on Earth. Since the inception of early civilization, humans have utilized plants for several purposes, particularly for their medicinal value. While some plants are known for their toxicity, they also contain beneficial phytochemicals that are important for both plants and humans, indicating their dual nature. This study aims to explore and synthesize the existing knowledge on various poisonous plant species found worldwide. It primarily focuses on the therapeutic potential of specific types of phytochemicals responsible for treating multiple diseases. This review includes a list of 70 poisonous plants with medicinal properties for treating various ailments, as well as some of their traditional uses. A few of these plants are emphasized, which have been tremendously explored and studied, hold significant potential to contribute to modern drug discovery. Furthermore, it addresses the possible prospects and challenges of using poisonous plants and their phytochemicals as therapeutic agents. Although the therapeutic potential of poisonous plants is substantial, many toxins remain unexplored. This review accentuates the need for rigorous scientific investigations, prior to clinical trials to validate their traditional uses, which would reveal the pharmacological interventions that will eventually advance human health and well-being.

Functional iridoid synthases from iridoid producing and non-producing Nepeta species (subfam. Nepetoidae, fam. Lamiaceae)

Iridoids, a class of atypical monoterpenes, exhibit exceptional diversity within the Nepeta genus (subfam. Nepetoidae, fam. Lamiaceae).The majority of these plants produce iridoids of the unique stereochemistry, with nepetalactones (NLs) predominating; however, a few Nepeta species lack these compounds. By comparatively analyzing metabolomics, transcriptomics, gene co-expression, and phylogenetic data of the iridoid-producing N. rtanjensis Diklić & Milojević and iridoid-lacking N. nervosa Royle & Bentham, we presumed that one of the factors responsible for the absence of these compounds in N. nervosa is iridoid synthase (ISY). Two orthologues of ISY were mined from leaves transcriptome of N. rtanjensis (NrPRISE1 and NrPRISE2), while in N. nervosa only one (NnPRISE) was identified, and it was phylogenetically closer to the representatives of the Family 1 isoforms, designated as P5βRs. Organ-specific and MeJA-elicited profiling of iridoid content and co-expression analysis of IBG candidates, highlighted NrPRISE2 and NnPRISE as promising candidates for ISY orthologues, and their function was confirmed using in vitro assays with recombinant proteins, after heterologous expression of recombinant proteins in E. coli and their His-tag affinity purification. NrPRISE2 demonstrated ISY activity both in vitro and likely in planta, which was supported by the 3D modeling and molecular docking analysis, thus reclassification of NrPRISE2 to NrISY is accordingly recommended. NnPRISE also displays in vitro ISY-like activity, while its role under in vivo conditions was not here unambiguously confirmed. Most probably under in vivo conditions the NnPRISE lacks substrates to act upon, as a result of the loss of function of some of the upstream enzymes of the iridoid pathway. Our ongoing work is conducted towards re-establishing the biosynthesis of iridoids in N. nervosa.