数据之源，洞见之始

1-Kestose is a fructooligosaccharide. An oligosaccharide is a saccharide polymer containing a small number (typically three to six) of component sugars, also known as simple sugars. They are generally found either O- or N-linked to compatible amino acid side chains in proteins or to lipid moieties.

Bradykinin is a vasoactive kinin that is liberated from its substrate kininogen by the action of kallikrein, and is known to be involved in a wide range of biologic processes. It may play an important role in blood pressure regulation and the maintenance of normal blood flow. Moreover, in various pathologic states of the cardiovascular system, it appears to provide protective actions against ischemic injury, ventricular hypertrophy, congestive heart failure, and thrombosis. Bradykinin is a potent vasodilator that acts through endothelial B2 kinin receptors to stimulate the release of nitric oxide and endothelium-derived hyperpolarizing factor. Bradykinin deficiency states may play a role in some forms of hypertension, and a relative deficiency in bradykinin may be a contributing factor to worsening heart failure. Experimental studies revealed that mice lacking the B2 receptor gene were more likely to develop hypertension, cardiac hypertrophy, and myocardial damage. Kinins exert several biologic actions. They are involved in nociception, inflammation, capillary permeability, reactive hyperemia, and stimulation of cellular glucose uptake. Bradykinin is a polypeptide that circulates in the plasma in very low concentrations in comparison with the amount of bradykinin found in various body tissues. Kininogens ([alpha] 2 globulins) are synthesized in the liver and circulate at high concentrations in the plasma. There are two kininogenases that convert kininogens into bradykinin: plasma kallikrein, also known as Fletcher factor, and glandular kallikrein, also known as tissue kallikrein. (PMID: 11975815).

The ATP-dependent carboxylate-amine/thiol ligase superfamily is known to contain enzymes catalyzing the formation of various types of peptide, one of which is d-alanyl-d-alanine.(PMID: 16030213). The glycopeptide antibiotic vancomycin acts by binding to the D-alanyl-D-alanine terminus of the cell wall precursor lipid II in the cytoplasmic membrane.(PMID: 17418637). D-alanine-D-alanine ligase from Thermotoga maritima ATCC 43589 (TmDdl) was a useful biocatalyst for synthesizing D-amino acid dipeptides.D-Alanine-D-alanine ligase (Ddl) catalyzes the biosynthesis of an essential bacterial peptidoglycan precursor D-alanyl-D-alanine and it represents an important target for development of new antibacterial drugs. (PMID: 17267218). D-Alanyl-D-alanine is a microbial metabolite.

Dimethylbenzimidazole is an intermediate in Riboflavin metabolism. Dimethylbenzimidazole is the second to last step for the synthesis of alpha-Ribazole. It is converted from Riboflavin then it is converted to N1-(5-Phospho-alpha-D-ribosyl)-5,6-dimethylbenzimidazole via the enzyme nicotinate-nucleotide--dimethylbenzimidazole phosphoribosyltransferase (EC 2.4.2.21).

Deoxyuridine triphosphate (dUTP) is a deoxynucleotide triphosphate (dNTP) that is chemically similar to uridine triphosphate (UTP) except that it has a deoxyribose sugar instead of a ribose sugar. DNA synthesis requires the availability of deoxynucleotide triphosphates (dTTP, dATP, dGTP, dCTP), whereas RNA synthesis requires the availability of nucleotide triphosphates (NTPs) such as TTP, ATP, GTP, and UTP. The conversion of nucleotide triphosphates (NTPs) into dNTPs can only be done in the diphosphate form. Typically, an NTP has one phosphate removed to become an NDP. This is then converted into a dNDP by an enzyme called ribonucleotide reductase and followed by the re-addition of phosphate to give a dNTP. dUTP is a substrate for several enzymes, including inosine triphosphate pyrophosphatase, deoxyuridine 5'-triphosphate nucleotidohydrolase (mitochondrial), uridine-cytidine kinase 1, nucleoside diphosphate kinase 3, nucleoside diphosphate kinase B, nucleoside diphosphate kinase 6, nucleoside diphosphate kinase (mitochondrial), nucleoside diphosphate kinase homolog 5, nucleoside diphosphate kinase A, and nucleoside diphosphate kinase 7. While UTP is routinely incorporated into RNA, dUTP is not normally incorporated into DNA. Instead, if dUTP is misincorporated into DNA, it can cause DNA damage. Therefore, dUTP can be considered as a teratogen or a mutagen. The extent of DNA damage caused by dUTP is highly dependent on the levels of the dUTP pyrophosphatase (dUTPase) and uracil-DNA glycosylase (UDG), which limits the intracellular accumulation of dUTP. Additionally, loss of viability following thymidylate synthase (TS) inhibition occurs as a consequence of the accumulation of dUTP in some cell lines and subsequent misincorporation of uracil into DNA (PMID: 11487279).

L-Histidinol, a structural analogue of the essential amino acid L-histidine, enhances the toxicity of a variety of anticancer drugs for many tumour cells of animal origin (PMID:8297120). L-Histidinol inhibits human myristoyl-CoA:protein-myristoyltransferase (hNMT), an essential eukaryotic enzyme that catalyzes the cotranslational transfer of myristate into the NH2-terminal glycine residue of a number of important proteins of diverse function (PMID:9778369).

Melezitose, also spelled melicitose, is a nonreducing trisaccharide sugar that is produced by many plant sap eating insects, including aphids such as Cinara pilicornis by an enzyme reaction. This is beneficial to the insects, as it reduces the stress of osmosis by reducing their own water potential. The melezitose is part of the honeydew which acts as an attractant for ants and also as a food for bees. This is useful to the lice as they have a symbiotic relationship with ants. Melezitose can be partially hydrolyzed to glucose and turanose the latter of which is an isomer of sucrose (Wikipedia).

N-Acetyl-b-glucosaminylamine is the product of a reaction catalyzed vy the enzyme N(4)-(beta-N-acetylglucosaminyl)-L-asparaginase [EC 3.5.1.26, Aspartylglucosaminidase, AGA]. AGA is a key enzyme in the catabolism of N-linked oligosaccharides of glycoproteins. It cleaves the asparagine from the residual N-acetylglucosamines as one of the final steps in the lysosomal breakdown of glycoproteins. Aspartylglucosaminuria (AGU) is a lysosomal disease caused by deficiency of N-aspartyl-beta-glucosaminidase. AGU is the only known lysosomal storage disease caused by an amidase deficiency. (OMIM208400).

Ureidosuccinic acid, also known as L-ureidosuccinate or carbamyl-L-aspartate, belongs to the class of organic compounds known as aspartic acids and derivatives. Aspartic acids and derivatives are compounds containing an aspartic acid or a derivative thereof resulting from reaction of aspartic acid at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom. Ureidosuccinic acid is also classified as a carbamate derivative. It is a solid that is soluble in water. Ureidosuccinic acid exists in all living species, ranging from bacteria to plants to humans. Ureidosuccinic acid can be biosynthesized from carbamoyl phosphate and L-aspartic acid through the action of the enzyme known as aspartate carbamoyltransferase (ACTase) and serves as an intermediate in pyrimidine biosynthesis. In humans, a drop in the level of urinary ureidosuccinic acid is associated with bladder cancer (PMID: 25562196). It is also involved in the metabolic disorder called Canavan disease.

Orotidylic acid (OMP), is a pyrimidine nucleotide which is the last intermediate in the biosynthesis of uridine monophosphate. Decarboxylation by Orotidylate decarboxylase affords Uridine 5'-phosphate which is the route to Uridine and its derivatives de novo and consequently one of the most important processes in nucleic acid synthesis (Dictionary of Organic Compounds). In humans, the enzyme UMP synthase converts OMP into uridine 5'- monophosphate. If UMP synthase is defective, orotic aciduria can result. (Wikipedia).

myo-Inositol 6-phosphate, also known as I6P or Ins(6)P, belongs to the class of organic compounds known as inositol phosphates. Inositol phosphates are compounds containing a phosphate group attached to an inositol (or cyclohexanehexol) moiety. Inositol phosphate is an intermediate step in the metabolism of glucose-6-phosphate into myo-inositol. myo-Inositol is synthesized from glucose-6-phosphate (G-6-P) in two steps. First, G-6-P is isomerized by INYNA1 into myo-inositol 1-phosphate, which is then dephosphorylated by IMPA1 to give myo-inositol.

UDP-N-acetylmuraminate is a nucleoside diphosphate sugar which is formed from UDP-N-acetylglucosamine and phosphoenolpyruvate. It serves as the building block upon which peptidoglycan is formed.