HOME
ListMoto - Canavanine


--- Advertisement ---



L-(+)-(S)- Canavanine
Canavanine
is a non-proteinogenic amino acid found in certain leguminous plants. It is structurally related to the proteinogenic α-amino acid L-arginine, the sole difference being the replacement of a methylene bridge (-CH 2- unit) in arginine with an oxa group (i.e., an oxygen atom) in canavanine. Canavanine
Canavanine
is accumulated primarily in the seeds of the organisms which produce it, where it serves both as a highly deleterious defensive compound against herbivores and a vital source of nitrogen for the growing embryo[1] (see also L-canaline). The mechanism of canavanine's toxicity is that organisms that consume it typically mistakenly incorporate it into their own proteins in place of L-arginine, thereby producing structurally aberrant proteins that may not function properly.

Chemical structure of canavanine compared to arginine

Some specialized herbivores tolerate L-canavanine either because they metabolize it efficiently (cf. L-canaline) or avoid its incorporation into their own nascent proteins. An example of this ability can be found in the larvae of the tobacco budworm Heliothis
Heliothis
virescens, which can tolerate massive amounts of dietary canavanine. These larvae fastidiously avoid incorporation of L-canavanine into their nascent proteins (presumably by virtue of highly discriminatory Arginine—tRNA ligase, the enzyme responsible for the first step in the incorporation of arginine into proteins). In contrast, larvae of the tobacco hornworm Manduca
Manduca
sexta can only tolerate tiny amounts (1.0 microgram per kilogram of fresh body weight[2]) of dietary canavanine because their arginine-tRNA ligase has little, if any, discriminatory capacity. No one has examined experimentally the arginine-tRNA synthetase of these organisms. But comparative studies of the incorporation of radiolabeled L-arginine and L-canavanine have shown that in Manduca
Manduca
sexta, the ratio of incorporation is about 3 to 1. Dioclea megacarpa seeds contain high levels of canavanine. The beetle Caryedes brasiliensis is able to tolerate this however as it has the most highly discriminatory arginine-tRNA ligase known. In this insect, the level of radiolabeled L-canavanine incorporated into newly synthesized proteins is barely measurable. Moreover, this beetle uses canavanine as a nitrogen source to synthesize its other amino acids to allow it to develop.[3] NZB/W F1, NZB, and DBA/2 mice fed L-canavanine develop a syndrome similar to systemic lupus erythematosus,[4] while BALB/c mice fed a steady diet of protein containing 1% canavanine showed no change in lifespan.[5] The toxicity of canavanine may be enhanced under conditions of protein starvation,[4] and canavanine toxicity resulting from consumption of Hedysarum alpinum
Hedysarum alpinum
seeds, which contain quantities of canavanine around 1%, has been implicated in the death of Christopher McCandless.[6] Alfalfa
Alfalfa
seeds and sprouts contain L-canavanine. The L-canavanine in alfalfa has been linked to lupus-like symptoms in primates, including humans, and other auto-immune diseases. Often stopping consumption reverses the problem.[7][8][9] See also[edit]

Canaline Arginine

References[edit]

^ "Non-protein amino acids (NPA)". January 2009. Archived from the original on 2011-01-22. Retrieved 2011-01-22. [self-published source?] ^ Rosenthal, G. A.; Dahlman, D. L. (1986). "L- Canavanine
Canavanine
and protein synthesis in the tobacco hornworm Manduca
Manduca
sexta". Proceedings of the National Academy of Sciences. 83 (1): 14–8. Bibcode:1986PNAS...83...14R. doi:10.1073/pnas.83.1.14. JSTOR 26787. PMC 322781 . PMID 3455753.  ^ Rosenthal, G. A.; Hughes, C. G.; Janzen, D. H. (1982). "L-Canavanine, a Dietary Nitrogen
Nitrogen
Source for the Seed
Seed
Predator Caryedes brasiliensis (Bruchidae)". Science. 217 (4557): 353–5. Bibcode:1982Sci...217..353R. doi:10.1126/science.217.4557.353. PMID 17791516.  ^ a b Akaogi, Jun; Barker, Tolga; Kuroda, Yoshiki; Nacionales, Dina C.; Yamasaki, Yoshioki; Stevens, Bruce R.; Reeves, Westley H.; Satoh, Minoru (2006). "Role of non-protein amino acid l-canavanine in autoimmunity". Autoimmunity Reviews. 5 (6): 429–35. doi:10.1016/j.autrev.2005.12.004. PMID 16890899.  ^ Brown, Dan L (2005). "Canavanine-induced longevity in mice may require diets with greater than 15.7% protein". Nutrition & Metabolism. 2 (1): 7. doi:10.1186/1743-7075-2-7. PMC 554090 . PMID 15733319.  ^ Krakauer, Jon. "How Chris McCandless Died: An Update". The New Yorker. Retrieved 12 February 2015.  ^ Montanaro, A; Bardana Jr, E. J. (1991). "Dietary amino acid-induced systemic lupus erythematosus". Rheumatic diseases clinics of North America. 17 (2): 323–32. PMID 1862241.  ^ Herbert, V; Kasdan, T. S. (1994). "Alfalfa, vitamin E, and autoimmune disorders". The American Journal of Clinical Nutrition. 60 (4): 639–40. PMID 8092103. [unreliable medical source?] ^ http://vegpeace.org/rawfoodtoxins.html[full citation needed][unreliable medical source?]

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (January 2011) (Learn how and when to remove this template message)

Bibliography[edit]

Rosenthal, Gerald A. (1986). "Biochemical insight into insecticidal properties ofl-Canavanine, a higher plant protective allelochemical". Journal of Chemical Ecology. 12 (5): 1145–56. doi:10.1007/BF01639001. PMID 24307052.  Rosenthal, G. A.; Berge, M. A.; Bleiler, J. A.; Rudd, T. P. (1987). "Aberrant, canavanyl protein formation and the ability to tolerate or utilize L-canavanine". Experientia. 43 (5): 558–61. doi:10.1007/BF02143585. PMID 3582574. 

v t e

Nitric oxide
Nitric oxide
signaling modulators

Forms

Nitroxyl
Nitroxyl
anion (NO−; oxonitrate(1-), hyponitrite anion) Nitric oxide
Nitric oxide
(NO⋅; nitrogen monoxide) Nitrosonium
Nitrosonium
(NO+; nitrosyl cation)

Targets

sGC

Activators: Cinaciguat
Cinaciguat
(BAY 58-2667) Riociguat
Riociguat
(BAY 63-2521)

Inhibitors: ODQ

NO donors (prodrugs)

Nitrates: Diethylene glycol dinitrate
Diethylene glycol dinitrate
(DEGDN) Erythritol tetranitrate
Erythritol tetranitrate
(ETN) Ethylene glycol dinitrate
Ethylene glycol dinitrate
(EGDN; nitroglycol) Isosorbide mononitrate
Isosorbide mononitrate
(ISMN) Isosorbide dinitrate
Isosorbide dinitrate
(ISDN) Itramin tosilate Mannitol hexanitrate Naproxcinod
Naproxcinod
(nitronaproxen; AZD-3582, HCT-3012) NCX-466 NCX-2216 NCX-4016 NCX 4040 NCX-4215 Nicorandil Nipradilol
Nipradilol
(K-351) Nitrate
Nitrate
(NO− 3) Nitroatorvastatin (NCX-6560) Nitroflurbiprofen (HCT-1026) Nitrofluvastatin Nitroglycerin (glyceryl trinitrate (GTN)) Nitropravastatin (NCX-6550) Pentaerithrityl tetranitrate
Pentaerithrityl tetranitrate
(PETN) Propatylnitrate Propylene glycol dinitrate
Propylene glycol dinitrate
(PGDN) Sodium trioxodinitrate (Angeli's salt) Tenitramine Trolnitrate

Nitroso compounds/nitrites: Nitrite
Nitrite
(NO− 2); O-Nitroso compounds (alkyl nitrites): Amyl nitrite
Amyl nitrite
(isoamyl nitrite, isopentyl nitrite) Cyclohexyl nitrite Ethyl nitrite Hexyl nitrite Isobutyl nitrite
Isobutyl nitrite
(2-methylpropyl nitrite) Isopropyl nitrite Methyl nitrite n-Butyl nitrite Pentyl nitrite tert-Butyl nitrite; S-Nitroso compounds (thionitrites): LA810 S-Nitrosoalbumin (SNALB) S-Nitrosated AR545C S-Nitroso-N-acetylcysteine (SNAC) S-Nitroso-N-acetylpenicillamine
S-Nitroso-N-acetylpenicillamine
(SNAP) S-Nitroso-N-valerylpenicillamine (SNVP) S-Nitrosocaptopril (SNO-Cap) S-Nitrosocysteine (SNC, CysNO, SNO-Cys) S-Nitrosodiclofenac S-Nitrosoglutathione
S-Nitrosoglutathione
(GSNO, SNOG) SNO-t-PA SNO-vWF; N-Nitroso compounds (e.g., nitrosamines): SIN-1A

Nitrosyl compounds: Metal nitrosyl complexes: Roussin's black salt Roussin's red salt Sodium nitroprusside
Sodium nitroprusside
(SNP)

NONOates (diazeniumdiolates): Diethylamine/NO (DEA/NO) Diethylenetriamine/NO (DETA/NO) GLO/NO JS-K Methylamine hexamethylene methylamine/NO (MAHMA/NO) PROLI/NO Spermine/NO (SPER/NO) V-PYRRO/NO

Heterocyclic compounds: Furoxans: Furoxan REC15/2739; Sydnonimines: Feprosidnine Linsidomine
Linsidomine
(SIN-1) Molsidomine
Molsidomine
(SIN-10) Sydnonimine

Unsorted: CXL-1427 FK-409 FR144220 FR146881 N-Acetyl-N-acetoxy-4-chlorobenzenesulfonamide

Enzyme (inhibitors)

NOS

nNOS

3-Bromo-7-nitroindazole 3-Chloroindazole 3-Chloro-5-nitroindazole 5-Nitroindazole 6-Nitroindazole 7-Nitroindazole A-84643 Aminoguanidine
Aminoguanidine
(pimagedine) ARL-17477 Indazole N5-(1-Iminoethyl)-L-ornithine (L-NIO) Nω-Methyl-L-arginine (L-NMA) Nω-Propyl-L-arginine (L-NPA) Nitroarginine
Nitroarginine
(NNA, NOARG) Pentamidine isethionate TRIM

iNOS

1-Amino-2-hydroxyguanidine 2-Ethylaminoguanidine 2-Iminopiperidine 1400W AEITU Aminoguanidine
Aminoguanidine
(pimagedine) AMT AR-C 102222 BYK-191023 Canavanine Cindunistat (SD-6010) EITU IPTU MITU N5-(1-Iminoethyl)-L-ornithine (L-NIO) N6-(1-Iminoethyl)-L-lysine (L-NIL) Nω-Methyl-L-arginine (L-NMA) Ronopterin (VAS-203) TRIM

eNOS

Aminoguanidine
Aminoguanidine
(pimagedine) N5-(1-Iminoethyl)-L-ornithine (L-NIO) Nω-Methyl-L-arginine (L-NMA) Nitroarginine
Nitroarginine
(NNA, NOARG)

Unsorted

Asymmetric dimethylarginine
Asymmetric dimethylarginine
(ADMA) CKD-712 Guanidinoethyldisulfide (GED) GW-273629 Indospicine KD-7040 Nitroarginine
Nitroarginine
methyl ester (NAME) NCX-456 NXN-462 ONO-1714 VAS-2381

Arginase

ABH Nω-Hydroxy-L-arginine (NOHA)

CAMK

Calmidazolium W-7

Others

Precursors: L-Arginine Nω-Hydroxy-L-arginine (NOHA)

Cofactors: NADPH FAD FMN Heme BH4 CaM O2 Ca2+

Indirect/downstream NO modulators: ACE inhibitors/AT-II receptor antagonists (e.g., captopril, losartan) ETB receptor antagonists (e.g., bosentan) L-Type calcium channel
L-Type calcium channel
blockers (e.g., dihydropyridines: nifedipine) Nebivolol
Nebivolol
(beta blocker) PDE5 inhibitors (e.g., sildenafil) Statins (e.g., simvastatin)

See also: Receptor/signaling modulators

v t e

Non-proteinogenic amino acids

Plant cell wall

Hydroxyproline

bacterial cell wall

Lanthionine Norleucine Diaminopimelic acid

neurotransmitters

gamma-Aminobutyric acid (GABA) Quisqualic acid
Quisqualic acid
(toxic)

human toxins

ADDA (amino acid) Canavanine thialysine Azetidine-2-carboxylic acid Quisqualic acid

Medical/Health

Beta-peptides

β-Alanine β-Leucine

Antibiotic

2-Aminoisobutyric acid
2-Aminoisobutyric acid
(AIB) Enduracididine

clotting factors

Carboxyglutamic acid

Other

4-Aminobenzoic acid
4-Aminobenzoic acid
(PABA) Aminolevulinic acid
Aminolevulinic acid
(metabolism) Canaline
Canaline
(insectiside) Penicillamine
Penicillamine
(chelation) Norleucine
Norleucine
(Alzheimers) Dihydroxyphenylglycine
Dihydroxyphenylglycine
(DHPG) Sarcosine Norvaline Homocysteine
Homocysteine
(heart) Hydroxyproline
Hydroxyproline
(collagen) Hypusine

Abiotic amino acids

List of abiotic amino acids

Engineered amino acids

Expanded genetic code

Intermediates

Mitochondria
Mitochondria
citric acid cycle

Ornithine Citrulline

Aminolevulinic acid
Aminolevulinic acid
(5-ALA) Cystine

Amino acids
Amino acids
types: Encoded (proteins) Essential Non-proteinogenic Ketogenic Glucogenic Imino acids D-amino acids

.