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Albumin esterase activity

Naphthol AS-acetate (3-acetoxynaphthoic acid anilide] [1163-67-3] M 305.3, m 152°, 160°. Recrystd from hot MeOH and dried in vacuo over P2O5. It is slightly soluble in AcOH, EtOH, CHCI3 or CgHg. It is a fluorogenic substrate for albumin esterase activity. [Chen and Scott Analyt Letters 17 857 1984], At kgx 320nm it had fluorescence at 500nm. [Brass and Sommer B 61 1000 1928]. [Pg.498]

Human oxyhemoglobin (oxyHb A) hydrolyzes 4-nitrophenyl acetate at a higher rate than bovine serum albumin [107], It has been proposed that imidazole catalysis by /3-His2 is primarily responsible for the esterase activity, and... [Pg.87]

Semm albumin is not an enzyme but a transport protein, yet it has demonstrated hydrolytic activity against a variety of xenobiotic substrates. This este-rase-like activity has been known for years, but there is still confusion in the literature regarding its nature and mechanism. Indeed, it was not clear whether this activity is intrinsic to the albumin molecule or results from contamination of albumin preparations by one or more hydrolytic enzymes. More-recent studies with highly purified human serum albumin (HSA) have confirmed that the protein has an intrinsic esterase activity toward several substrates, but that activity due to contaminants and particularly semm cholinesterase is involved... [Pg.88]

Whereas the above evidence clearly points to a catalytic activity of serum albumin, it does not exclude an activity toward less-reactive substrates due to contamination of some HSA preparations. Indeed, the hypothesis of a contamination by plasma cholinesterase (EC 3.1.1.8) has been raised [126][127]. The efficient hydrolysis of nicotinate esters by HSA (see Chapt. 8) [128][129] could be due to contamination by cholinesterase in samples of a commercially available, essentially fatty acid free albumin. Support for this hypothesis was obtained when HSA contaminated with cholinesterase was resolved into two peaks by affinity chromatography, and the esterase activity toward nicotinate esters was found exclusively in the cholinesterase fraction [130],... [Pg.90]

A. Matsushima, H. Sasaki, Y. Kodera, Y. Inada, Reduction of Immunoreactivity of Bovine Serum Albumin Conjugated with Polyethylene Glycol (PEG) in Relation to Its Esterase Activity , Biochem. Int. 1992, 26, 485-490. [Pg.96]

Y. Ozeki, Y. Kurono, T. Yotosuyanagi, K. Ikeda, Effects of Drug Binding on the Esterase Activity of Human Serum Albumin Inhibition Modes and Binding Sites of Anionic Drugs , Chem. Pharm. Bull. 1980, 28, 535-540. [Pg.96]

N. Dubois-Presle, F. Lapicque M. H. Maurice, S. Fournel-Gigleux, J. Magdalou, M. Abiteboul, G. Siest, P. Netter, Stereoselective Esterase Activity of Human Serum Albumin toward Ketoprofen Glucuronide , Mol. Pharmacol. 1995, 47, 647 - 653. [Pg.755]

In the presence of human serum albumin, the H spectrum of acetyl-salicyclic acid is specifically shifted and broadened [119]. The interpretation of changes in T, and T2 require several theoretical assumptions. These have been discussed in detail [120] for JV-acetylsulphanilamide and acetate binding to the active site of carbonic anhydrase. It was concluded that the acetyl groups of these inhibitors have a motion additional to that of the enzyme. It can be shown by NMR that acetate binds to two sites on the enzyme, only one of which is inhibitory to esterase activity (methyls are 4.3 and 4.8 A from the metal in the Mn substituted enzyme [121]). Strict care must be taken to avoid paramagnetic impurities when NMR relaxation enhancement by diamagnetic macromolecules is being studied. A preparation of carbonic anhydrase, for example, can contain 0.24 paramagnetic Cu atoms per Zn atom [122]. [Pg.181]

Fig. 11. Electrophoretic distribution in agar of gastric mucosal extract protein (A) protease activity at pH 2.2 (B) carboxylic esterase activity (C) and immuno-electrophoretic pattern (D). The relative mobility is shown at the bottom (UR) with 0 representing the location of the uncharged dextran, levan and 1 the migration of human serum albumin. The zones of mobility (Z), arbitrarily defined on the basis of protein distribution, are indicated at the top. Each antigen and enzyme is designated by the zone in which it is found. The antigens are alsc designated by a letter. From Kushner et al. (K32). Fig. 11. Electrophoretic distribution in agar of gastric mucosal extract protein (A) protease activity at pH 2.2 (B) carboxylic esterase activity (C) and immuno-electrophoretic pattern (D). The relative mobility is shown at the bottom (UR) with 0 representing the location of the uncharged dextran, levan and 1 the migration of human serum albumin. The zones of mobility (Z), arbitrarily defined on the basis of protein distribution, are indicated at the top. Each antigen and enzyme is designated by the zone in which it is found. The antigens are alsc designated by a letter. From Kushner et al. (K32).
Mo.st OP pesticides react preferentially with BuChE. In contrast, most OP nerve agents react preferentially with AChE. Carboxylesterase is also highly reactive with most OPs. This complicate.s the comparison of studies on rodents with studie,s on monkeys and humans because rodenhs have very high concentrations of carboxylesterase in plasma, whereas monkeys and humans have no carboxylesterase in plasma. On the other hand, albumin has esterase activity (Means and Wu, 1979), and this is sometimes mistaken for carboxylesterase activity in human plasma. [Pg.706]

Yang, R, Bian, C., Zhu, L., Zhao, G., Huang, Z., and Huang, M. 2007. Effect of human serum albumin on drug metabolism Structural evidence of esterase activity of human serum albumin. J. Struct. Biol. 157 348-355. [Pg.1002]

Kurono, Y., Maki, T., Yotsuyanagi, T., and Ikeda, K. 1979. Esterase-like activity of human-serum albumin— structure-activity-relationships for the reactions with phenyl acetates and para-nitrophenyl esters. Chem Pharm Bull 27 2781-86. [Pg.404]

Albumins exhibit esterase-like activities for carboxy-lesters, as reported years ago (Tildon and Ogilvie, 1972 Means and Bender, 1975 Kokubo et al., 1982). These esterase activities are based in the reversible acylation of a tyrosine residue of the sequence Arg-Tyr-Thr-Arg (position 410 in bovine serum albumin and 411 in human serum albumin) (Peters, 1996a). However, it has also been suggested that this activity, at least in human serum albumin, is the result of the irreversible acetylation of 82 different amino acid residues rather than reversible acylations (Lockridge et al., 2008). [Pg.864]

Lockridge, O., Xue, W, Gaydess, A., et al., 2008. Pseudo-esterase activity of human albumin slow turnover on tyrosine 411 and stable acetylation of 82 residues including 59 lysines. J. Biol. Chem. 283 (33), 22582-22590. [Pg.872]

Serum albumin is the most abundant protein in blood plasma. Its primary function is to control the colloidal osmotic pressure in blood, but is also important for its buffering capacity and for its ability to transport fatty acids and bilirubin, as well as xenobiotic molecules. The physiological implications of its esterase-like activity are unknown (see Sect. 3.7.5). [Pg.57]

It is important to note that acetylsalicylic acid and some 4-nitrophenyl esters are quite reactive species that easily acylate nucleophiles. With such compounds, albumin indeed behaves as a catalyst, but it is simultaneously a target, and the term esterase-like activity can only be understood with this restriction in mind. [Pg.89]

K. Ohta, Y. Kurono, K. Ikeda, Esterase-Like Activity of Human Serum Albumin II Reaction with V-iraws -Cinnamoyl-Imidazoles , J. Pharm. Sci. 1983, 72, 385-388. [Pg.96]

A. Salvi, P. A. Carrupt, J. M. Mayer, B. Testa, Esterase-Like Activity of Human Serum Albumin toward Prodrug Esters of Nicotinic Acid , Drug Metab. Dispos. 1997, 25, 395-398. [Pg.97]


See other pages where Albumin esterase activity is mentioned: [Pg.550]    [Pg.465]    [Pg.465]    [Pg.550]    [Pg.465]    [Pg.465]    [Pg.292]    [Pg.96]    [Pg.770]    [Pg.771]    [Pg.1053]    [Pg.454]    [Pg.183]    [Pg.246]    [Pg.483]    [Pg.456]    [Pg.834]    [Pg.835]    [Pg.864]    [Pg.1108]    [Pg.19]    [Pg.89]    [Pg.97]   
See also in sourсe #XX -- [ Pg.1107 ]




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