Camalexin

Last updated
Camalexin
Camalexin.svg
Names
Preferred IUPAC name
3-(1,3-Thiazol-2-yl)-1H-indole
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.236.489 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
  • InChI=1S/C11H8N2S/c1-2-4-10-8(3-1)9(7-13-10)11-12-5-6-14-11/h1-7,13H
    Key: IYODIJVWGPRBGQ-UHFFFAOYSA-N
  • InChI=1/C11H8N2S/c1-2-4-10-8(3-1)9(7-13-10)11-12-5-6-14-11/h1-7,13H
    Key: IYODIJVWGPRBGQ-UHFFFAOYAV
  • c1ccc2c(c1)c(c[nH]2)c3nccs3
Properties
C11H8N2S
Molar mass 200.26 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Camalexin (3-thiazol-2-yl-indole) is a simple indole alkaloid found in the plant Arabidopsis thaliana and other crucifers. The secondary metabolite functions as a phytoalexin to deter bacterial and fungal pathogens. [1]

Contents

Structure

The base structure of camalexin consists of an indole ring derived from tryptophan. The ethanamine moiety attached to the 3 position of the indole ring is subsequently rearranged into a thiazole ring.

Biosynthesis

While the biosynthesis of camalexin in planta has not been fully elucidated, most of the enzymes involved in the pathway are known and involved in a metabolon complex. [2] The pathway starts with a tryptophan precursor which is subsequently oxidized by two cytochrome P450 enzymes. [3] The indole-3-acetaldoxime is then converted to indole-3-acetonitrile by another cytochrome P450, CYP71A13. [1] A glutathione conjugate followed by a subsequent unknown enzyme is needed to form dihydrocamalexic acid. [4] [5] A final decarboxylation step by cytochrome P450 CYP71B15, also called phytoalexin deficient4 (PAD3) results in the final product, camalexin. [6] [7]

Biological activity

Camalexin is cytotoxic against aggressive prostate cancer cell lines in vitro . [8]

Related Research Articles

Gibberellins (GAs) are plant hormones that regulate various developmental processes, including stem elongation, germination, dormancy, flowering, flower development, and leaf and fruit senescence. GAs are one of the longest-known classes of plant hormone. It is thought that the selective breeding of crop strains that were deficient in GA synthesis was one of the key drivers of the "green revolution" in the 1960s, a revolution that is credited to have saved over a billion lives worldwide.

<span class="mw-page-title-main">Cytochrome P450</span> Class of enzymes

Cytochromes P450 (CYPs) are a superfamily of enzymes containing heme as a cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance of various compounds, as well as for hormone synthesis and breakdown. In 1963, Estabrook, Cooper, and Rosenthal described the role of CYP as a catalyst in steroid hormone synthesis and drug metabolism. In plants, these proteins are important for the biosynthesis of defensive compounds, fatty acids, and hormones.

<span class="mw-page-title-main">Indole-3-acetic acid</span> Chemical compound

Indole-3-acetic acid is the most common naturally occurring plant hormone of the auxin class. It is the best known of the auxins, and has been the subject of extensive studies by plant physiologists. IAA is a derivative of indole, containing a carboxymethyl substituent. It is a colorless solid that is soluble in polar organic solvents.

<span class="mw-page-title-main">Glucobrassicin</span> Chemical compound

Glucobrassicin is a type of glucosinolate that can be found in almost all cruciferous plants, such as cabbages, broccoli, mustards, and woad. As for other glucosinolates, degradation by the enzyme myrosinase is expected to produce an isothiocyanate, indol-3-ylmethylisothiocyanate. However, this specific isothiocyanate is expected to be highly unstable, and has indeed never been detected. The observed hydrolysis products when isolated glucobrassicin is degraded by myrosinase are indole-3-carbinol and thiocyanate ion, which are envisioned to result from a rapid reaction of the unstable isothiocyanate with water. However, a large number of other reaction products are known, and indole-3-carbinol is not the dominant degradation product when glucosinolate degradation takes place in crushed plant tissue or in intact plants.

<span class="mw-page-title-main">Lanosterol 14 alpha-demethylase</span>

Lanosterol 14α-demethylase (CYP51A1) is the animal version of a cytochrome P450 enzyme that is involved in the conversion of lanosterol to 4,4-dimethylcholesta-8(9),14,24-trien-3β-ol. The cytochrome P450 isoenzymes are a conserved group of proteins that serve as key players in the metabolism of organic substances and the biosynthesis of important steroids, lipids, and vitamins in eukaryotes. As a member of this family, lanosterol 14α-demethylase is responsible for an essential step in the biosynthesis of sterols. In particular, this protein catalyzes the removal of the C-14α-methyl group from lanosterol. This demethylation step is regarded as the initial checkpoint in the transformation of lanosterol to other sterols that are widely used within the cell.

In enzymology, a 4-hydroxyphenylacetaldehyde oxime monooxygenase (EC 1.14.13.68) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Sterol 14-demethylase</span> Class of enzymes

In enzymology, a sterol 14-demethylase (EC 1.14.13.70) is an enzyme of the Cytochrome P450 (CYP) superfamily. It is any member of the CYP51 family. It catalyzes a chemical reaction such as:

Tyrosine N-monooxygenase (EC 1.14.13.41, tyrosine N-hydroxylase, CYP79A1) is an enzyme with systematic name L-tyrosine,NADPH:oxygen oxidoreductase (N-hydroxylating). This enzyme catalyses the following chemical reaction

3-Epi-6-deoxocathasterone 23-monooxygenase (EC 1.14.13.112, cytochrome P450 90C1, CYP90D1, CYP90C1) is an enzyme with systematic name 3-epi-6-deoxocathasterone,NADPH:oxygen oxidoreductase (C-23-hydroxylating). This enzyme catalyses the following chemical reaction

Valine N-monooxygenase (EC 1.14.13.118, CYP79D1, CYP79D2) is an enzyme with systematic name L-valine,NADPH:oxygen oxidoreductase (N-hydroxylating). This enzyme catalyses the following chemical reaction

Phenylalanine N-monooxygenase (EC 1.14.13.124, phenylalanine N-hydroxylase, CYP79A2) is an enzyme with systematic name L-phenylalanine,NADPH:oxygen oxidoreductase (N-hydroxylating). This enzyme catalyses the following chemical reaction

Tryptophan N-monooxygenase (EC 1.14.13.125, tryptophan N-hydroxylase, CYP79B1, CYP79B2, CYP79B3) is an enzyme with systematic name L-tryptophan,NADPH:oxygen oxidoreductase (N-hydroxylating). This enzyme catalyses the following chemical reaction

Indole-2-monooxygenase (EC 1.14.13.137, BX2 (gene), CYP71C4 (gene)) is an enzyme with systematic name indole,NAD(P)H:oxygen oxidoreductase (2-hydroxylating). This enzyme catalyses the following chemical reaction

3-hydroxyindolin-2-one monooxygenase (EC 1.14.13.139, BX4 (gene), CYP71C1 (gene)) is an enzyme with systematic name 3-hydroxyindolin-2-one,NAD(P)H:oxygen oxidoreductase (2-hydroxy-2H-1,4-benzoxazin-3(4H)-one-forming). This enzyme catalyses the following chemical reaction

2-Hydroxy-1,4-benzoxazin-3-one monooxygenase (EC 1.14.13.140, BX5 (gene), CYP71C3 (gene)) is an enzyme with systematic name 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one,NAD(P)H:oxygen oxidoreductase (N-hydroxylating). This enzyme catalyses the following chemical reaction

Carotene epsilon-monooxygenase (EC 1.14.99.45, CYP97C1, LUT1) is an enzyme with systematic name alpha-carotene:oxygen oxidoreductase (3-hydroxylating). This enzyme catalyses the following chemical reaction

<span class="mw-page-title-main">Pisatin</span> Chemical compound

Pisatin (3-hydroxy-7-methoxy-4′,5′-methylenedioxy-chromanocoumarane) is the major phytoalexin made by the pea plant Pisum sativum. It was the first phytoalexin to be purified and chemically identified. The molecular formula is C17H14O6.

Elizabeth S. Sattely is an American scientist and biotechnology engineer. She is an Associate Professor of Chemical Engineering in the Department of Chemical Engineering, an HHMI investigator, and a ChEM-H Faculty Fellow at Stanford University.

Cytochrome P450, family 710, also known as CYP710, is a plant cytochrome P450 monooxygenase family, the proteins encoded by its family members are mainly sterol 22-desaturase, which was widely distributed in plants, and take participate in Phytosteroidogenesis. CYP710 family is considered to be the plant orthologous of fungi CYP61 family, which is lost in animal. The CYP61/CYP710 ancestor gene diverged from a gene duplication of ancestor CYP51 in early eukaryotes

Juniperic acid or 16-hydroxyhexadecanoic acid is an omega-hydroxy long-chain fatty acid that is palmitic acid which is substituted at position 16 by a hydroxy group. Palmitic acid is converted to juniperic acid by cytochrome P450 various enzymes, including CYP704B22.

References

  1. 1 2 Nafisi, Majse; Goregaoker, Sameer; Botanga, Christopher J.; Glawischnig, Erich; Olsen, Carl E.; Halkier, Barbara A.; Glazebrook, Jane (2007). "Arabidopsis Cytochrome P450 Monooxygenase 71A13 Catalyzes the Conversion of Indole-3-Acetaldoxime in Camalexin Synthesis". The Plant Cell. 19 (6): 2039–2052. doi:10.1105/tpc.107.051383. PMC   1955726 . PMID   17573535.
  2. Mucha, Stefanie; Heinzlmeir, Stephanie; Kriechbaumer, Verena; Strickland, Benjamin; Kirchhelle, Charlotte; Choudhary, Manisha; Kowalski, Natalie; Eichmann, Ruth; Hueckelhoven, Ralph; Grill, Erwin; Kuster, Bernhard; Glawischnig, Erich (2019). "The formation of a camalexin-biosynthetic metabolon". The Plant Cell. 31 (11): 2697–2710. doi: 10.1105/tpc.19.00403 . PMC   6881122 . PMID   31511315.
  3. Glawischnig, E.; Hansen, B. G.; Olsen, C. E.; Halkier, B. A. (2004). "Camalexin is synthesized from indole-3-acetaldoxime, a key branching point between primary and secondary metabolism in Arabidopsis". Proceedings of the National Academy of Sciences. 101 (21): 8245–8250. Bibcode:2004PNAS..101.8245G. doi: 10.1073/pnas.0305876101 . PMC   419588 . PMID   15148388.
  4. Su, Tongbing; Xu, Juan; Li, Yuan; Lei, Lei; Zhao, Luo; Yang, Hailian; Feng, Jidong; Liu, Guoqin; Ren, Dongtao (2011). "Glutathione-Indole-3-Acetonitrile is Required for Camalexin Biosynthesis in Arabidopsis thaliana". The Plant Cell. 23 (1): 364–380. doi:10.1105/tpc.110.079145. PMC   3051237 . PMID   21239642.
  5. Geu-Flores, Fernando; Møldrup, Morten Emil; Böttcher, Christoph; Olsen, Carl Erik; Scheel, Dierk; Halkier, Barbara Ann (2011). "Cytosolic γ-Glutamyl Peptidases Process Glutathione Conjugates in the Biosynthesis of Glucosinolates and Camalexin in Arabidopsis". The Plant Cell. 23 (6): 2456–2469. doi:10.1105/tpc.111.083998. PMC   3160024 . PMID   21712415.
  6. Zhou, Nan; Tootle, Tina L.; Glazebrook, Jane (1999). "Arabidopsis PAD3, a Gene Required for Camalexin Biosynthesis, Encodes a Putative Cytochrome P450 Monooxygenase". The Plant Cell. 11 (12): 2419–2428. doi:10.1105/tpc.11.12.2419. PMC   144139 . PMID   10590168.
  7. Schuhegger, Regina; Nafisi, Majse; Mansourova, Madina; Petersen, Bent Larsen; Olsen, Carl Erik; Svatoš, Aleš; Halkier, Barbara Ann; Glawischnig, Erich (2006). "CYP71B15 (PAD3) Catalyzes the Final Step in Camalexin Biosynthesis". Plant Physiology. 141 (4): 1248–1254. doi: 10.1104/pp.106.082024 . PMC   1533948 . PMID   16766671.
  8. Smith, Basil A.; Neal, Corey L.; Chetram, Mahandranauth; Vo, Baohan; Mezencev, Roman; Hinton, Cimona; Odero-Marah, Valerie A. (2013). "The phytoalexin camalexin mediates cytotoxicity towards aggressive prostate cancer cells via reactive oxygen species". Journal of Natural Medicines. 67 (3): 607–618. doi:10.1007/s11418-012-0722-3. PMC   3644009 . PMID   23179315.