Inosinic acid

Inosinic acid
Names
	IUPAC name 5'-Inosinic acid
	Other names IMP; Hypoxanthine ribotide;
Identifiers
CAS Number	131-99-7;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:17202;
ChEMBL	ChEMBL1233478;
ChemSpider	8264;
ECHA InfoCard	100.004.588
E number	E630(flavour enhancer)
IUPHAR/BPS	5124;
MeSH	Inosine+monophosphate
PubChemCID	8582;
UNII	TAO7US05G5;
CompTox Dashboard(EPA)	DTXSID10859884 DTXSID4044294, DTXSID10859884;
	InChI InChI=1S/C10H13N4O8P/c15-6-4(1-21-23(18,19)20)22-10(7(6)16)14-3-13-5-8(14)11-2-12-9(5)17/h2-4,6-7,10,15-16H,1H2,(H,11,12,17)(H2,18,19,20)/t4-,6-,7-,10-/m1/s1 Key: GRSZFWQUAKGDAV-KQYNXXCUSA-N; InChI=1/C10H13N4O8P/c15-6-4(1-21-23(18,19)20)22-10(7(6)16)14-3-13-5-8(14)11-2-12-9(5)17/h2-4,6-7,10,15-16H,1H2,(H,11,12,17)(H2,18,19,20)/t4-,6-,7-,10-/m1/s1 Key: GRSZFWQUAKGDAV-KQYNXXCUBU;
	SMILES O=C3/N=C\Nc1c3ncn1[C@@H]2O[C@@H]([C@@H](O)[C@H]2O)COP(=O)(O)O;
Properties
Chemical formula	C10H13N4O8P
Molar mass	348.208g·mol−1
	Except where otherwise noted, data are given for materials in theirstandard state(at 25 °C [77 °F], 100 kPa). verify(what is?) Infobox references

Inosinic acidorinosine monophosphate(IMP) is anucleotide(that is, anucleosidemonophosphate). Widely used as a flavor enhancer, it is typically obtained from chicken byproducts or othermeat industrywaste. Inosinic acid is important inmetabolism.It is theribonucleotideofhypoxanthineand the first nucleotide formed during the synthesis ofpurinenucleotides. It can also be formed by thedeaminationofadenosine monophosphatebyAMP deaminase.It can behydrolysedtoinosine.

The enzyme deoxyribonucleoside triphosphate pyrophosphohydrolase, encoded by YJR069C inSaccharomyces cerevisiaeand containing (d)ITPase and (d)XTPase activities, hydrolyzesinosine triphosphate(ITP) releasingpyrophosphateand IMP.^[1]

Important derivatives of inosinic acid include the purine nucleotides found innucleic acidsandadenosine triphosphate,which is used to storechemical energyinmuscleand other tissues.

In the food industry, inosinic acid and itssaltssuch asdisodium inosinateare used asflavor enhancers.It is known asE numberreferenceE630.

Inosinate synthesis

The inosinate synthesis is complex, beginning with a5-phosphoribosyl-1-pyrophosphate(PRPP).Enzymestaking part in IMP synthesis constitute a multienzyme complex in the cell. Evidence demonstrates that there are multifunctional enzymes, and some of them catalyze non-sequential steps in the pathway.^{[citation needed]}

Synthesis of other purine nucleotides

Within a few steps inosinate becomesAMPorGMP.^[2]Both compounds areRNA nucleotides.^[2]AMP differs from inosinate by the replacement of IMP's carbon-6 carbonyl with an amino group. The interconversion of AMP and IMP occurs as part of thepurine nucleotide cycle.^[3]GMP is formed by the inosinate oxidation toxanthylate(XMP), and afterwards adds an amino group on carbon 2. Hydrogen acceptor on inosinate oxidation isNAD+.Finally, carbon 2 gains the amino group by spending an ATP molecule (which becomes AMP+2Pi). While AMP synthesis requires GTP, GMP synthesis uses ATP. That difference offers an important regulation possibility.

Regulation of purine nucleotide biosynthesis

Inosinate and many other molecules inhibit the synthesis of 5-phosphoribosylaminefrom 5-phosphoribosyl-1-pyrophosphate (PRPP), disabling the enzyme that catalyzes the reaction: glutamine-5-phosphoribosyl-1-pyrophosphate-amidotransferase. In other words, when levels of inosinate are high, glutamine-5-phosphoribosyl-1-pyrophosphate-amidotransferase is inhibited, and, as a consequence, inosinate levels decrease. Also, as a result, adenylate and guanylate are not produced, which means that RNA synthesis cannot be completed because of the lack of these two important RNA nucleotides.

Applications

Inosinic acid can be converted into varioussaltsincludingdisodium inosinate(E631),dipotassium inosinate(E632), andcalcium inosinate(E633). These three compounds are used asflavor enhancersfor the basic tasteumamior savoriness with a comparatively high effectiveness. They are mostly used in soups, sauces, and seasonings for the intensification and balance of the flavor of meat.

References

^Davies O, Mendes P, Smallbone K, Malys N (2012)."Characterisation of multiple substrate-specific (d)ITP/(d)XTPase and modelling of deaminated purine nucleotide metabolism".BMB Reports.45(4): 259–64.doi:10.5483/BMBRep.2012.45.4.259.PMID 22531138.
^^a ^bMader, M. M.; Henry, J. R. (2007-01-01), Taylor, John B.; Triggle, David J. (eds.),"7.03 - Antimetabolites",Comprehensive Medicinal Chemistry II,Oxford: Elsevier, pp. 55–79,doi:10.1016/b0-08-045044-x/00204-2,ISBN 978-0-08-045044-5,retrieved2020-12-17
^Voet, D, Voet, J. G., Biochemistry (3rd Edition), John Wiley & Sons, Inc., 2004, pg 1095