Natural products physiological role

Bell EA. 1981. The physiological role(s) of secondary (natural) products. In Conn EE, editor. The Biochemistry of Plants. Volume 7, Secondary Plant Products. New York Academic Press, pp. 1-19. 

McKey D (1974) Adaptive patterns in alkaloid physiology. Am Nat 108 305-320 Molis M, Korner J, Ko YW, Kim JH, Wahl M (2006) Inducible responses in the brown seaweed Ecklonia cava the role of grazer identity and season. J Ecol 94 243-249 Moore BS (2006) Biosynthesis of marine natural products macroorganisms (Part B). Nat Prod Rep 23 615-629... 

Compounds showing vitamin K activity are substituted naphthoquinones. The parent compound, 2-methyl-1,4-naphthoquinone, does show some biological activity as do other similar but synthetic compounds. The production of the complete naturally active forms is thought to depend upon the addition of an isoprene chain at position 3 on the aromatic ring. Differences in this side chain produce the various K vitamins (Figure 12.10). A most important physiological role of vitamin K is in the synthesis of the blood clotting factors, II (prothrombin), VII, IX and X. 

In Chapter 3, the group of Prof. Herbert Waldmann at the Max Plank Institute for Molecular Physiology provides a rationale on how natural products which play historically a predominant role in drug discovery are efficiently used in combination with protein structure similarity clustering to inspire directed compound library design and target identification. 

A third role of natural products is their utility as prototypes or models for synthetic drugs possessing physiological activities similar to the original drug. Procaine and similar local anesthetics are commonly cited representatives of this category. 

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