Related Experiment Video
Updated: Jun 21, 2026
07:59
A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Evolution of morphine biosynthesis in opium poppy
Jörg Ziegler1, Peter J Facchini, René Geissler
1Leibniz-Institute of Plant Biochemistry, Halle, Germany.
Phytochemistry
|August 12, 2009
Summary
Researchers identified salutaridine reductase (SalR) as a key enzyme in morphinan alkaloid production in opium poppies. This enzyme, a monomeric short-chain dehydrogenase/reductase, is crucial for synthesizing specific plant compounds.
Area of Science:
- Plant biochemistry and metabolomics
- Molecular biology and gene expression
- Natural product biosynthesis
Background:
- Benzylisoquinoline alkaloids (BIAs) are diverse plant secondary metabolites with significant pharmaceutical potential.
- (S)-reticuline is a central intermediate in BIA metabolism, leading to various alkaloid subclasses.
- Morphinan alkaloids, a subclass of BIAs, are predominantly found in the opium poppy (Papaver somniferum).
Purpose of the Study:
- To identify novel enzymes involved in morphinan alkaloid biosynthesis in Papaver species.
- To characterize the function and properties of salutaridine reductase (SalR), a key enzyme in this pathway.
- To investigate the evolutionary origins of morphinan alkaloid-specific enzymes.
Main Methods:
- Comparative transcriptome analysis of P. somniferum and related species lacking morphinan alkaloids.
- Identification and isolation of novel cDNAs encoding pathway enzymes, including SalR.
- Heterologous overexpression and functional characterization of SalR.
- Homology modeling and substrate docking to elucidate the enzyme's active site.
Main Results:
- Three novel cDNAs, including salutaridine reductase (SalR), were identified and shown to be co-expressed with known BIA biosynthetic genes.
- SalR was successfully overexpressed and confirmed as a monomeric short-chain dehydrogenase/reductase (SDR) specific for morphinan alkaloid production.
- Structural analysis revealed the substrate binding site of SalR, differentiating it from other plant SDRs involved in different metabolic pathways.
Conclusions:
- Salutaridine reductase (SalR) is a critical, specialized enzyme for morphinan alkaloid biosynthesis in Papaver species.
- The study suggests that morphinan alkaloid biosynthesis may have evolved through the recruitment of monomeric SDRs from plant defense pathways.
- Understanding SalR's function provides insights into the evolution of specialized metabolic pathways in plants.
Related Concept Videos
01:20Opioid Analgesics: Morphine and Other Natural Cogeners
Opioids are a class of drugs that mimic endogenous opioid peptides and act on opioid receptors, and help in pain relief. These compounds are classified as natural, synthetic, or semi-synthetic. Natural opioids, like morphine, codeine, and thebaine, are derived from the opium poppy plant (Papaver somniferum or Papaver album) and are termed opiates. Synthetic opioids are artificial, while semi-synthetic opioids combine natural and synthetic compounds. Morphine, a prototypical opioid, possesses a...
01:15Opioid Analgesics: Synthetic and Semisynthetic Opioids
Synthetic and semisynthetic opioids are pivotal in pain management and tackling opioid addiction. Semisynthetic opioids, including morphinans (morphine derivatives), oxycodone, oxymorphone, hydrocodone, and hydromorphone, have improved pharmacokinetic profiles compared to morphine. Additionally, heroin and 6-MAM (6-Monoacetylmorphine) show better CNS penetration than morphine due to heightened lipid solubility. Hydromorphone, a potent opioid, undergoes hepatic metabolism to form the active...
01:22Opioid Receptors: Overview
Opioid receptors, including the mu (μ, MOR), delta (δ, DOR), and kappa (κ, KOR) types, belong to the rhodopsin family of G protein-coupled receptors. These receptors are located throughout the central and peripheral nervous systems and in non-neuronal tissues such as macrophages and astrocytes. Opioid receptor ligands can be categorized into agonists or antagonists. Highly selective agonists include [d-Ala2, MePhe4, Gly(ol)5]-enkephalin or DAMGO for MOR, [D-Pen2, D-Pen5]-enkephalin or DPDPE for...
01:25Analgesia and Pain Management
Pain is critical to various clinical pathologies, provoking an urgent need for effective management. Pain, whether acute or chronic, is a complex neurochemical process. Its alleviation depends on the type, with nonopioid analgesics effective for mild to moderate pain, such as musculoskeletal or inflammatory pain, while neuropathic pain responds best to anticonvulsants, tricyclic antidepressants, or serotonin/norepinephrine reuptake inhibitors. For severe acute or chronic pain, opioids may be...
01:28Biosynthesis of Nucleic Acids
Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...
01:29Biosynthesis of Lipids
Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis pathway, which...