Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0393754 (HSA)
 2,996 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two fragments were isolated from BSA one was derived from the first terminal third of the molecule and the second from the last third of the molecule. Each fragment inhibited the reaction of BSA-anti BSA by 90% or better. An immunoabsorbent of each bound 90% of anti BSA. Each fragment bound two antibody molecules per mole of fragment. These results are explained by the concept that BSA contains repeating identical or similar antigenic determinants. Conformational non identity of various batches of BSA was revealed by reactivity of the disulfide bonds at the neutral transition. Trypsin was found to cleave GSA, PSA, and HSA to yield an immunochemically reactive fragment. At least in the case of HSA, the fragment exhibited all the immunochemical reactivity of the native protein.
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PMID:Immunochemistry of bovine serum albumin. 8 78

A clinical study with 99mTc-DTPA-galactosyl serum albumin (99mTc-GSA) was performed in 10 patients with hepatobiliary disease. In this study, scintigraphic data and images with 99mTc-GSA were compared with several serological liver function tests, the hepatic blood perfusion index and image quality using 99mTc-DTPA-human serum albumin (99mTc-HSA). Dynamic and serial hepatic images were obtained over a 20 min period after 99mTc-GSA injection, and time activity curves from the heart and liver were generated. The blood clearance index (HH15), and the hepatic uptake index (LHL15) were calculated from each curve of the heart and liver, respectively. In addition, using two compartment fitting, the blood clearance (KH1, KH2) index was calculated, and using exponential fitting, the hepatic uptake index (KL) was calculated. The mean HH15 in LC group and non-LC group was 0.81 +/- 0.05, 0.64 +/- 0.10, respectively. The mean LHL15 in LC group and non-LC group was 0.79 +/- 0.04, 0.91 +/- 0.06, respectively. There were significant differences between non-LC group and LC group in HH15, and LHL15, KH1 and KL. There were also significant correlations of KH1 with HH15, and KL with LHL15. Parameters of 99mTc-GSA showed significant correlations with various liver functions. 99mTc-GSA scintigraphy showed clearer liver images in hepatobiliary diseases than 99mTc-HSA. These results suggest that 99mTc-GSA scintigraphy is useful in estimating preserved liver function and hepatic morphology.
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PMID:[Clinical application of 99mTc-DTPA-galactosyl serum albumin in hepatobiliary disease]. 846 7

For evaluating the hepatic function, intrinsic substances are influenced by the physiological activity of homeostasis. Potential reduction of the hepatic reserve can be evaluated by the loading of the extrinsic substances. Asialoglycoprotein (ASGP) receptor reduces its activity according to the grade of hepatic parenchymal injury. The quantitative evaluation was possible with 99mTc-galactosyl HSA (99mTc-GSA) using an index of GSARmax by a multi-compartment analysis. The correlation between GSARmax and the histological activity index (HAI) score of the liver in hepatectomized cases was better than that of the ICGR15. A safe limit of GSARmax was 0.3 mg/min for 1 segment excision and 0.35 mg/min for 2 or 3 segment excision. Some cases showed discrepancies between 99mTc-GSA and ICGR15. ICG mainly reflected hepatic blood flow and GSA was related to both the amount of functional hepatocytes and flow. Regional distribution of GSARmax presented functional SPECT image of the liver. Since the scale was common, the comparison were possible between SPECT images in different studies. In reservoir treatment, the injection of 99mTc-MAA in a catheter made it possible to estimate the distribution of the anticancer agent. The incorrect perfusion to the digestive tracts and shunt flow to the lung were monitored, and it was also useful to predict the therapeutic effect.
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PMID:[Nuclear medicine of the liver--focusing on functional diagnosis]. 1035 54

Bilirubin albumin solution gave an emission spectrum in the wavelength range 500-600 nm with emission maxima at 528 nm when excited at 487 nm. The magnitude of fluorescence intensity increased on increasing bilirubin/albumin molar ratio. At three different albumin concentrations, namely, 1.0, 2.5 and 10.0 microM, there was an initial linear increase in fluorescence up to a molar ratio 1.0 in all cases beyond which it sloped off or decreased. This fluorescence enhancement was used to calculate the binding parameters of bilirubin-albumin interaction and the value of binding constant was found to be 1.72 x 10(7) l/mol similar to the published values obtained with other methods. Different serum albumins, namely, human (HSA), goat (GSA), pig (PSA) and dog serum albumins (DSA) bound bilirubin with almost the same affinity when studied by the technique of fluorescence enhancement. Bilirubin albumin interaction was also studied at different pH and ionic strengths. There was a decrease in bilirubin-albumin complex formation on either decreasing the pH from 9.0 to 7.0 or increasing the ionic strength from 0.15 to 1.0. These results suggest that the technique of fluorescence enhancement can be used successfully to study the bilirubin-albumin interaction.
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PMID:Use of fluorescence enhancement technique to study bilirubin-albumin interaction. 1045 76

Chloroform-induced conformational changes of bilirubin (BR) bound to different serum albumins were studied by circular dichroism (CD) and fluorescence spectroscopy. Addition of a small amount of chloroform ( approximately 20 mM) to a solution containing 20 microM albumin and 15 microM BR changed the sign order and magnitude of the characteristic CD spectra of all BR-albumin complexes except BR-PSA complex which showed abnormal behavior. Monosignate negative CD Cotton effects (CDCEs) of BR complexed with SSA, GSA and BuSA were transformed into bisignate CDCEs in presence of chloroform akin to those exhibited by chloroform free solution of BR-HSA complex, indicating that the pigment acquired right handed plus (P) chirality when chloroform was added to these complexes. Bisignate CD spectra of BR complexed with HSA and BSA showed complete inversion upon addition of chloroform corroborating earlier findings. On the other hand, changes observed with BR-RSA complex were slightly different showing an additional CD band of weak intensity centered around 390 nm though inversion of CDCEs was similar to that of BR-HSA complex. Monosignate CD spectra of BR-PSA complex also showed three CD bands occurring at 409, 470 and 514 nm after chloroform addition. These results indicated significant but different effects of chloroform on the conformation of bound BR in BR-albumin complexes which can be ascribed to the changes in the exciton chirality of bilirubin probably due to altered hydrophobic microenvironment induced by the binding of chloroform at or near the ligand binding site. Chloroform severely quenched the intrinsic tryptophan fluorescence of the protein and shifted the emission maxima towards blue region in all the albumins except PSA. However, quantitative differences in both quenching and blue shift were noted in different serum albumins. This suggests that chloroform probably binds in the close vicinity of tryptophan residue(s) located in subdomain(s) IIA or IB and II both. The fluorescence of BR-albumin complexes was also found to be sensitive to the presence of a small amount of chloroform. But the changes observed in the fluorescence of the bound pigment in presence of chloroform were less marked as compared to the changes in the intrinsic fluorescence of protein per se. Taken together, these results suggest that there is at least one conserved site for chloroform binding in all these albumins which is at or near the BR binding site.
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PMID:Chloroform-induced conformational changes in the bound pigmentin bilirubin-albumin complexes. 1086 3

The role of internal lysine residues of different serum albumins, viz. from human, rabbit, goat, sheep and buffalo (HSA, RbSA, GSA, SSA and BuSA), in conformational stability and bilirubin binding was investigated after blocking them using acetylation, succinylation and guanidination reactions. No significant change in the secondary structure was noticed whereas the tertiary structure of these proteins was slightly altered upon acetylation or succinylation as revealed by circular dichroism (CD), fluorescence and gel filtration results. Guanidination did not affect the native protein conformation to a measurable extent. Scatchard analysis, CD and absorption spectroscopic results showed marked reductions (5-21-fold decrease in K(a) and approximately 50% decrease in the CD Cotton effect intensity) in the affinity of albumins for bilirubin upon acetylation or succinylation whereas guanidination produced a small change. Interestingly, monosignate CD spectra of bilirubin complexed with GSA, SSA and BuSA were transformed to bisignate CD spectra upon acetylation or succinylation of internal lysine residues whereas spectra remained bisignate in the case of bilirubin bound to acetylated or succinylated derivatives of HSA and RbSA. When probed by CD spectroscopy, bilirubin bound to acetylated or succinylated derivatives of GSA and SSA rapidly switched over to native albumins and not vice versa. These results suggested that salt linkage(s) contributed by internal lysine residue(s) play an important role in the high-affinity binding of bilirubin to albumin and provide stability to the native three-dimensional conformation of the bound pigment. Chloroform severely decreased the intensity of both positive and negative CD Cotton effects of bilirubin complexed with acetylated or succinylated derivatives of all albumins which otherwise increased significantly in the case of bilirubin complexed with native and guanidinated albumin derivatives, except the bilirubin-RbSA complex which showed a small decrease in intensity. These results suggest that the presence of salt linkage(s) in bilirubin-albumin complexation is(are) crucial to bring about effective and efficient stereochemical changes in the bound pigment by co-binding of chloroform which seems to have at least one conserved binding site on these albumins that is shared with bilirubin.
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PMID:Understanding the role of internal lysine residues of serum albumins in conformational stability and bilirubin binding. 1134 52

Bilirubin (BR) binding properties of serum albumins from different mammalian species viz. human (HSA), equine (ESA), dog (DSA) and guinea pig (GPSA) were studied by absorption, fluorescence and CD spectroscopy. Whereas, a complex of BR with ESA produced maximum change, GPSA-BR complex showed weaker interaction as reflected from absorption and fluorescence spectroscopic data. Conformational analysis of these albumins by near- and far-UV CD spectra suggested similar structural characteristics (both secondary and tertiary structures) for ESA and HSA, whereas, DSA and GPSA had lower amounts of secondary and tertiary structures being minimum for GPSA. Photoirradiation results of BR-albumin complexes showed GPSA-bound BR more labile compared with other complexes, whereas, BR-ESA complex was found to be more stable against photoinduced chemical changes. Taken together, all these results suggest that chiroptical properties/stability of albumin bound BR varies with albumin species.
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PMID:Behavior of various mammalian albumins towards bilirubin binding and photochemical properties of different bilirubin-albumin complexes. 1256 27

Protein G-related albumin-binding (GA) modules are frequently expressed on the surfaces of bacterial cells. The limited amino acid sequence variation among GA modules results in structural and functional differences with possible implications for bacterial pathogenesis and host specificity. In particular, the streptococcal G148-GA3 and F. magna ALB8-GA albumin-binding domains exhibit a degree of structural and dynamic diversity that may account for their varied affinities for different species of albumin. To explore the impact of GA module polymorphisms on albumin binding and specificity, we recently used offset recombinant PCR to shuffle seven artificially constructed representatives of the GA sequence space and scan the phage-displayed recombinant domains for mutations that supported binding to the phylogenetically distinct human and guinea pig serum albumins (HSA and GPSA) (Rozak et al. (2006) Biochemistry 45, 3263-3271). Surprisingly, phage selection revealed an overwhelming preference for a single recombinant domain (PSD-1, phage-selected domain-1) regardless of whether the phages were enriched for their abilities to bind one or both of these albumins. We describe here the NMR-derived structure, dynamics, and stability of unbound PSD-1. Our results demonstrate that increased flexibility is not a requirement for broadened specificity, as had been suggested earlier (Johansson et al. (2002) J. Mol. Biol. 316, 1083-1099), because PSD-1 binds the phylogenetically diverse HSA and GPSA even more tightly than G148-GA3 but is less flexible. The structural basis for albumin-binding specificity is analyzed in light of these new results.
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PMID:Structure, dynamics, and stability variation in bacterial albumin binding modules: implications for species specificity. 1690 68

Interaction of bromophenol blue (BPB) with serum albumins from different mammalian species, namely, human (HSA), bovine (BSA), goat (GSA), sheep (SSA), rabbit (RbSA), porcine (PSA) and dog (DSA) was studied using absorption and absorption difference spectroscopy. BPB-albumin complexes showed significant differences in the spectral characteristics, i.e., extent of bathochromic shift and hypochromism relative to the spectral features of free BPB. Absorption difference spectra of these complexes also showed variations in the position of maxima and absorption difference (deltaAbs.) values. Absorption difference spectra of different bilirubin (BR)-albumin complexes showed a significant blue shift accompanied by decrease in deltaAbs. values in presence of BPB which were indicative of the displacement of bound BR from its binding site in BR-albumin complexes. These changes in the difference spectral characteristics of BR-albumin complexes were more marked at higher BPB concentration. However, the extent of these changes was different for different BR-albumin complexes. Taken together, all these results suggest that BPB partially shares BR binding site on albumin and different mammalian albumins show differences in the microenvironment of the BR/BPB binding site.
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PMID:Bromophenol blue binding to mammalian albumins and displacement of albumin-bound bilirubin. 1913 52

An optical probe, RG-(gal)(28)GSA, was synthesized to improve the detection of peritoneal implants by targeting the beta-d-galactose receptors highly expressed on the cell surface of a wide variety of cancers arising from the ovary, pancreas, colon, and stomach. Evaluation of RG-(gal)(28)GSA, RG-(gal)(20)GSA, glucose-analogue RG-(glu)(28)GSA, and control RG-HSA demonstrates specificity for the galactose, binding to several human adenocarcinoma cell lines, and cellular internalization. Studies using peritoneally disseminated SHIN3 xenografts in mice also confirmed a preference for galactose with the ability to detect submillimeter size lesions. Preliminary toxicity study for RG-(gal)(28)GSA using Balb/c mice reveal no toxic effects up to 100x of the standard imaging dose of 1 mg/kg administered either intraperitoneally or intravenously. These data indicate that RG-(gal)(28)GSA can selectively target a variety of human adenocarcinomas, can improve intraoperative or endoscopic tumor detection and resection, and may have little or no toxic in vivo effects; hence, it may be clinically translatable.
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PMID:Two-step synthesis of galactosylated human serum albumin as a targeted optical imaging agent for peritoneal carcinomatosis. 2010 20


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