Plant terpene specialized metabolism: complex networks or simple linear pathways?

Area of Science:

• Plant biochemistry and metabolic engineering.
• Evolutionary pathways of plant specialized metabolism.

Background:

• Classical models of plant biosynthesis often depict linear pathways, connecting central and specialized metabolism.
• Recent discoveries have revealed a more complex enzymatic foundation for plant chemistries, challenging linear perceptions.
• Plant specialized metabolism encompasses a vast array of compounds crucial for plant survival and interaction.

Approach:

• Reviewing illustrative examples of plant terpenoid metabolism.
• Analyzing the evolutionary strategies plants use to create chemical diversity.
• Focusing on diterpene, sesquiterpene, and monoterpene pathways.

Key Points:

• Plant metabolic pathways are best understood as complex networks, not linear routes.
• Branch points and multiple sub-routes are common, forming intricate metabolic grids.
• Terpenoid metabolism provides key examples of evolved networks driving chemical diversification.
• Scaffold formation and subsequent functionalization highlight pathway complexity.

Conclusions:

• Metabolic grids, rather than linear pathways, are the rule in plant specialized metabolism.
• Understanding these complex networks is critical for pathway evolution and engineering.
• This network concept has significant implications for biotechnological production of plant compounds.