Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Nverify (what is YN ?)
Infobox references
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.
v
t
e
GABA receptor modulators
Ionotropic
GABAA
Agonists: (+)-Catechin
Bamaluzole
Barbiturates (e.g., phenobarbital)
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
Phenibut
Picamilon
P4S
Progabide
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...
The Volkswagen Group MQB platform is the company's strategy for shared modular design construction of its transverse, front-engine, front-wheel-drive layout (optional front-engine, four-wheel-drive layout) automobiles. Volkswagen spent roughly $60bn [1] developing this new platform and the cars employing it. The platform underpins a wide range of cars from the supermini class to the mid size SUV class. MQB allows Volkswagen to assemble any of its cars based on this platform across all of its MQB ready factories. This allows the Volkswagen group flexibility to shift production as needed between its different factories. Beginning in 2012, Volkswagen Group marketed the strategy under the code name MQB , which stands for Modularer Querbaukasten , translating from German to "Modular Transversal Toolkit" or "Modular Transverse Matrix". [2] [3] MQB is one strategy within VW's overall MB (Modularer Baukasten or modular matrix) program which also includes th...
"NYPD" and "New York City Cops" redirect here. For other uses, see NYPD (disambiguation). Not to be confused with New York City Sheriff's Office or New York State Police. City of New York Police Department NYPD patch NYPD patrol officer's shield Flag of the New York City Police Department Common name New York City Police Department Abbreviation NYPD Motto Fidelis ad mortem (English: "Faithful Unto Death" ) Agency overview Formed May 23, 1845 ; 173 years ago ( 1845-05-23 ) Employees 55,304 Annual budget US$5.6 billion (2018) Jurisdictional structure Operations jurisdiction New York City, U.S. Map of City of New York Police Department's jurisdiction. Size 468.484 square miles (1,213.37 km 2 ) Population 8,537,673 [1] Legal jurisdiction New York City General nature Local civilian police Local civilian agency Headquarters 1 Police Plaza Park Row Lower Manhattan (across th...
Mixing
N verify (what is 
Y
N ?)
Comments
Post a Comment