Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Methylglyoxal, also called pyruvaldehyde or 2-oxopropanal, is the organic compound with the formula CH3C(O)CHO. Gaseous methylglyoxal has two carbonyl groups, an aldehyde and a ketone but in the presence of water, it exists as hydrates and oligomers.[1] It is a reduced derivative of pyruvic acid.
Contents
1Industrial production and biosynthesis
1.1Biochemistry
2Natural occurrence
3References
Industrial production and biosynthesis
Methylglyoxal is produced industrially by degradation of carbohydrates using overexpressed methylglyoxal synthase.[2]
In organisms, methylglyoxal is formed as a side-product of several metabolic pathways.[3] It may form from 3-aminoacetone, which is an intermediate of threonine catabolism, as well as through lipid peroxidation. However, the most important source is glycolysis. Here, methylglyoxal arises from nonenzymatic phosphate elimination from glyceraldehyde phosphate and dihydroxyacetone phosphate, two intermediates of glycolysis.
Aristolochic acid caused 12-fold increase of methylglyoxal from 18 to 231 μg/mg of kidney protein in poisoned mice.[4]
Biochemistry
Since methylglyoxal is highly cytotoxic, several detoxification mechanisms have evolved. One of these is the glyoxalase system. Methylglyoxal is detoxified by glutathione. Glutathione reacts with methylglyoxal to give a hemithioacetal, which converted into S-D-lactoyl-glutathione by glyoxalase I.[5] This thioester is hydrolyzedto D-lactate by glyoxalase II.[6]
The proximate and ultimate causes for biological methylglyoxal production remain unknown, but it may be involved in the formation of advanced glycation endproducts (AGEs).[7] In this process, methylglyoxal reacts with free amino groups of lysine and arginine and with thiol groups of cysteine forming AGEs. The heat shock protein 27 (Hsp27) is a specific target of posttranslational modification by methylglyoxal in human metastatic melanoma cells.[8]
Methylglyoxal binds directly to the nerve endings and by that increases the chronic extremity soreness in diabetic neuropathy.[9][10]
Other glycation agents include the reducing sugars:
glucose, the sugar that stores energy
galactose, a component of milk sugar (lactose)
allose, an all-cis hexose carried into the cell by special proteins
ribose, a component of RNA.
Natural occurrence
Due to increased blood glucose levels, methylglyoxal has higher concentrations in diabetics and has been linked to arterial atherogenesis. Damage by methylglyoxal to low-density lipoprotein through glycation causes a fourfold increase of atherogenesis in diabetics.[11]
Although methylglyoxal has been shown to increase carboxymethyllysine levels,[12] methylglyoxal has been suggested to be a better marker for investigating the association between AGEs with adverse health outcomes.
Methylglyoxal is a component of some kinds of honey, including manuka honey; it appears to have activity against E. coli and S. aureus and may help prevent formation of biofilms formed by P. aeruginosa .[13]
References
^Loeffler Kirsten W.; Koehler Charles A.; Paul Nichole M.; De Haan David O. (2006). "Oligomer Formation in Evaporating Aqueous Glyoxal and Methyl Glyoxal Solutions". Environmental Science & Technology. 40: 6318–6323. doi:10.1021/es060810w..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output .citation q{quotes:"""""""'""'"}.mw-parser-output .citation .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-maint{display:none;color:#33aa33;margin-left:0.3em}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
^Frieder W. Lichtenthaler "Carbohydrates as Organic Raw Materials" in Ullmann's Encyclopedia of Industrial Chemistry 2010, Wiley-VCH, Weinheim. doi: 10.1002/14356007.n05_n07
^Inoue Y, Kimura A (1995). "Methylglyoxal and regulation of its metabolism in microorganisms". Adv. Microb. Physiol. Advances in Microbial Physiology. 37: 177–227. doi:10.1016/S0065-2911(08)60146-0. ISBN 978-0-12-027737-7. PMID 8540421.
^Thornalley PJ (2003). "Glyoxalase I—structure, function and a critical role in the enzymatic defence against glycation". Biochem. Soc. Trans. 31 (Pt 6): 1343–8. doi:10.1042/BST0311343. PMID 14641060.
^Rabbani N; Godfrey, L; Xue, M; Shaheen, F; Geoffrion, M; Milne, R; Thornalley, PJ (May 26, 2011). "Glycation of LDL by methylglyoxal increases arterial atherogenicity. A possible contributor to increased risk of cardiovascular disease in diabetes". Diabetes. 60 (7): 1973–80. doi:10.2337/db11-0085. PMC 3121424. PMID 21617182.
^Cai, W., Uribarri, J., Zhu, L., Chen, X., Swamy, S., Zhao, Z., Grosjean, F., Simonaro, C., Kuchel, G. A., Schnaider-Beeri, M., Woodward, M., Striker, G. E., and Vlassara, H. (2014) Oral glycotoxins are a modifiable cause of dementia and the metabolic syndrome in mice and humans. PNAS 111.
^Israili, ZH (2014). "Antimicrobial properties of honey". American Journal of Therapeutics. 21 (4): 304–23. doi:10.1097/MJT.0b013e318293b09b. PMID 23782759.
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GABA receptor modulators
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GABAA
Agonists: (+)-Catechin
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BL-1020
DAVA
Dihydromuscimol
GABA
Gabamide
GABOB
Gaboxadol (THIP)
Homotaurine (tramiprosate, 3-APS)
Ibotenic acid
iso-THAZ
iso-THIP
Isoguvacine
Isomuscimol
Isonipecotic acid
Kojic amine
Lignans (e.g., honokiol)
Methylglyoxal
Monastrol
Muscimol
Nefiracetam
Neuroactive steroids (e.g., allopregnanolone)
Org 20599
PF-6372865
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Picamilon
P4S
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Propofol
Quisqualamine
SL-75102
TACA
TAMP
Terpenoids (e.g., borneol)
Thiomuscimol
Tolgabide
ZAPA
Positive modulators (abridged; see here for a full list): α-EMTBL
This article is part of a series on Information security Related security categories Internet security Cyberwarfare Computer security Mobile security Network security Threats Computer crime Vulnerability Eavesdropping Malware Spyware Ransomware Trojans Viruses Worms Rootkits Bootkits Keyloggers Screen scrapers Exploits Backdoors Logic bombs Payloads Denial of service Defenses Computer access control Application security Antivirus software Secure coding Secure by default Secure by design Secure operating systems Authentication Multi-factor authentication Authorization Data-centric security Encryption Firewall Intrusion detection system Mobile secure gateway Runtime application self-protection (RASP) v t e Information security , sometimes shortened to InfoSec , is the practice of preventing unauthorized access, use, disclosure, disruption, modification, inspection, recording or destruction of information. Th...
For other uses, see Monte Carlo (disambiguation). Quarter and ward of Monaco in Monaco Monte Carlo Quarter and ward of Monaco Monte Carlo in Monaco (Ward shown) Monte Carlo Location in relation to France Coordinates: 43°44′23″N 7°25′38″E / 43.73972°N 7.42722°E / 43.73972; 7.42722 Coordinates: 43°44′23″N 7°25′38″E / 43.73972°N 7.42722°E / 43.73972; 7.42722 Country Monaco Government • Type Principality Area • Urban 0.61 km 2 (.234 sq mi) Population • Quarter and ward of Monaco 15,200 (in the quarter) 3,500 (in the ward) Postcode 98000 Monte Carlo ( / ˈ m ɒ n t i ˈ k ɑːr l oʊ / ; Italian: [ˈmonte ˈkarlo] ; French: Monte-Carlo [mɔ̃te kaʁlo] , or colloquially Monte-Carl [mɔ̃te kaʁl] ; Monégasque: Munte Carlu ) officially refers to an administrative area of the Principality of Monaco, specifically the ward of Monte Carlo/Spélugues, where the Monte Carlo Casino is located. Informally the name also refers to a ...
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