Abstract:
:Thiol proteases are industrially significant proteins with catalytic efficiency. The effect of low, medium and high molecular-weight poly (ethylene glycol) (PEG- 400, 6000 and 20000) on the stability of thiol proteases (papain, bromelain and chymopapain) has been studied by activity measurements using synthetic substrate. Structural studies performed on papain by far UV circular dichroism spectroscopic measurements indicate that there is loss in secondary structure of the protein in presence of increasing concentration of PEGs. Intrinsic fluorescence measurements lead us to conclude that tryptophan residues of protein encounter non-polar microenvironment in presence of PEG solvent while acrylamide quenching shows greater accessibility of tryptophan residues of papain in presence of PEGs. Extrinsic fluorescence measurements lead us to conclude that PEGs bind to the hydrophobic sites on the protein and thus destabilize it. Thermal denaturation studies show that melting temperature of papain is decreased in presence of PEGs. Possible mechanism of destabilization is discussed next. The results imply that caution must be exercised in the use of PEGs with thiol proteases or hydrophobic proteins in general, for different industrial applications, even at room temperature.
journal_name
J Biochemjournal_title
Journal of biochemistryauthors
Fatima S,Khan RHdoi
10.1093/jb/mvm108subject
Has Abstractpub_date
2007-07-01 00:00:00pages
65-72issue
1eissn
0021-924Xissn
1756-2651pii
mvm108journal_volume
142pub_type
杂志文章abstract::The heparin-induced self-aggregation behaviours of four repeat peptides (R1-R4) in an acidic solution (pH = 4.5) were investigated by fluorescence and circular dichroism (CD) measurements and compared with those in a neutral solution (pH = 7.5). In contrast with the self-aggregation-resistive behaviours of the R1 and ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvm099
更新日期:2007-07-01 00:00:00
abstract::p-Nitrophenyl O-6-deoxy-6-[(2-pyridyl)amino]-alpha-D-glucopyranosyl-(1----4)-O-alpha- D-glucopyranosyl-(1----4)-O-alpha-D-glucopyranosyl-(1----4)-O-alpha-D- glucopyranosyl-(1----4)-alpha-D-glucopyranoside (FG5P) is hydrolyzed by human pancreatic a-amylase (HPA) or salivary alpha-amylase (HSA) to O-6-deoxy-6-[(2-pyridy...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a121841
更新日期:1986-11-01 00:00:00
abstract::The present data describe the mechanism of the inhibitory effects of human plasma apolipoproteins A-I and A-II on hydrolysis of triglyceride catalyzed by hepatic triglyceride lipase using a substrate of triolein particles stabilized with gum arabic in vitro. The experimental data could well be described by a model in ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a134000
更新日期:1982-09-01 00:00:00
abstract::A highly sensitive method was developed for quantitative analysis of phospholipid molecular species. Diradylglycerols prepared from phospholipids with phospholipase C were converted to the anthroyl-diradylglycerol derivatives, which could be separated into molecular species and sensitively quantified by reverse-phase ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a123399
更新日期:1991-03-01 00:00:00
abstract::Monoclonal antibodies were raised against a synthetic peptide (43 amino acid residues) that corresponds to the complete profragment of human prorenin. Seven monoclonal antibodies were chosen for further characterization. Two antibodies, 2-X-C1 and 4-X-E1, reacted with the middle region and C-terminus of the profragmen...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a122869
更新日期:1989-09-01 00:00:00
abstract::Ca2+-binding of S-100 protein was studied using a Ca2+ electrode at pH 6.80. In the presence of 0.1 M KCl and 10 mM MgCl2 (ionic strength 0.13), Ca2+-binding to S-100 protein occurred in three steps with positive cooperativity. The numbers of bound Ca2+ ions in the three steps were 2, 2, and 4. The Ca2+-binding consta...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a122596
更新日期:1988-12-01 00:00:00
abstract::An H2O2-generating fraction was prepared from porcine thyroid homogenate by differential and Percoll-density gradient centrifugations. The fraction consisted of mainly fragmented plasma membranes as judged by marker enzyme analysis and electron microscopy. The fraction produced H2O2 by reaction with NADPH only in the ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a122150
更新日期:1987-11-01 00:00:00
abstract::Pyridylamino sugar chains were converted to the corresponding reducing sugar chains by first converting them to 1-amino-1-deoxy derivatives using the method previously reported [S. Hase, J. Biochem. 112, 266-268 (1992)] and then converting the products to the corresponding reducing sugar chains using the Sommlet react...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvg112
更新日期:2003-07-01 00:00:00
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journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a123453
更新日期:1991-05-01 00:00:00
abstract::When meso-tetrakis(3-N-methylpyridiniumyl)porphyrin (m-TMPyP) formed a complex with poly[d(A-T)(2)], an intense bisignate excitonic CD in the Soret absorption region was observed. The excitonic CD of the m-TMPyP-poly[d(A-T)(2)] complex is unique in that no other combination of the related porphyrin, namely, meso-tetra...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvg046
更新日期:2003-03-01 00:00:00
abstract::A simple and rapid method to remove myosin light chain phosphatase from gizzard myosin using hydroxyapatite chromatography was developed. Stable phosphorylated myosin without light chain phosphatase and kinase was also prepared by the same procedure. A convenient method using the urea gel system to detect minor contam...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a134870
更新日期:1984-08-01 00:00:00
abstract::We previously showed that the 9 S estrogen receptor (ER) could be reconstituted from purified ER and purified heat shock protein 90 (hsp 90). So, we investigated the role of hsp 90 in the binding of purified ER to an estrogen responsive element (ERE) by using the reconstitution system. ER purified from calf uterus sho...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124593
更新日期:1994-10-01 00:00:00
abstract::The present study demonstrates that the functional counter-receptors for E-selectin at the cell surface of Colo201 human colon cancer cells are localized in detergent-insoluble membrane microdomains (DIM). Following isolation of counter-receptors from whole cell lysates using E-selectin-coupled magnetic beads followed...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvm107
更新日期:2007-07-01 00:00:00
abstract::The characteristics of the androgen receptor in the cytoplasmic fraction of Shionogi carcinoma 115 were studied in vitro by means of charcoal adsorption assay, sucrose density gradient centrifugation, and polyacrylamide gel electrophoresis. The equilibrium dissociation constant for [3H]dihydrotestosterone (Kd = (2-5) ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a133238
更新日期:1981-02-01 00:00:00
abstract::A new protein with a chain weight of approximately 220,000 was isolated from 0.6 M KI extracts of I-Z-I brushes of rabbit and chicken skeletal muscles, using (NH4)2SO4 precipitation and three column chromatographic procedures in succession. It was only possible to separate the high molecular weight protein from actin ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a133401
更新日期:1981-06-01 00:00:00
abstract::Isolation and characterization of a fibrous protein component which might be associated with contractile ring of a dividing Tetrahymena cell were attempted by making use of coprecipitation of the protein with rabbit skeletal muscle myosin. The protein was purified to homogeneity by ammonium sulfate fractionation betwe...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a133119
更新日期:1980-11-01 00:00:00
abstract::alpha-Actinin purified from chicken gizzard smooth muscle was characterized in comparison with alpha-actinins from chicken striated muscles, or fast-skeletal muscle, slow-skeletal muscle, and cardiac muscle. The gizzard alpha-actinin molecule consisted of two apparently identical subunits with a molecular weight of 10...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a134070
更新日期:1982-11-01 00:00:00
abstract::The complete amino acid sequence of coagulogen purified from the hemocytes of the horseshoe crab Carcinoscorpius rotundicauda was determined by characterization of the NH2-terminal sequence and the peptides generated after digestion of the protein with lysyl endopeptidase, Staphylococcal aureus protease V8 and trypsin...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a135283
更新日期:1985-08-01 00:00:00
abstract::Microtubule-associated protein (MAP) 1 consisting of MAP 1A and 1B was purified from rat brain by the poly-L-aspartic acid (PLAA) method. We found that MAP 1 bound to F-actin in vitro up to a molar ratio of MAP 1 to actin monomers of 1:10. The apparent binding constant was about 2.7 x 10(7) M-1. In contrast to the bin...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124263
更新日期:1993-12-01 00:00:00
abstract::Steroid monooxygenase of Rhodococcus rhodochrous is a Baeyer-Villigerase catalyzing the insertion of an oxygen atom between the C(17)- and C(20)-carbons of progesterone to produce testosterone acetate. The 5.1-kbp-long BamHI DNA fragment containing the steroid monooxygenase gene, smo, was cloned from the chromosomal D...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a022494
更新日期:1999-09-01 00:00:00
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journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvm210
更新日期:2008-02-01 00:00:00
abstract::Mitochondria have two independent protein-import machineries, one in the outer membrane (the Tom system) and the other in the inner membrane (the Tim system). Here, we have characterized the initial steps of precursor import into rat liver mitoplasts. The import reaction was separated into two stages, consisting of pr...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a022186
更新日期:1998-10-01 00:00:00
abstract::OsGEN-L has a 5'-flap endonuclease activity and plays an essential role in rice microspore development. The Class 4 RAD2/XPG family nucleases, including OsGEN-L, were recently found to have resolving activity for the Holliday junction (HJ), the intermediate of DNA strand recombination. In this study, we performed a de...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvr145
更新日期:2012-03-01 00:00:00
abstract::A transition-state analog, gluconolactone, was found to partially quench the protein fluorescence of glucoamylase [EC 3.2.1.3] from Rhizopus niveus. The interaction between gluconolactone and the enzyme was studied statically and kinetically at pH 4.5 in terms of fluorescence change. The dissociation constant Kd of th...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:
更新日期:1977-01-01 00:00:00
abstract::Two novel oligosaccharides with the sialyl-Le(a) structure were isolated from human milk using a monoclonal antibody, MSW 113. These oligosaccharides were purified by affinity chromatography on a column of the immobilized monoclonal antibody and by high-performance liquid chromatography, and structurally characterized...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124207
更新日期:1993-10-01 00:00:00
abstract::Activation of antiviral innate immunity is triggered by cellular pattern recognition receptors. Retinoic acid inducible gene-I (RIG-I)-like receptors (RLRs) detect viral non-self RNA in cytoplasm of virus-infected cells and play a critical role in the clearance of the invaded viruses through production of antiviral cy...
journal_title:Journal of biochemistry
pub_type: 杂志文章,评审
doi:10.1093/jb/mvv122
更新日期:2016-03-01 00:00:00
abstract::Mitochondria play many critical roles in cells, not only by supplying energy, but also by supplying metabolites, buffering Ca2+ levels and regulating apoptosis. During oocyte maturation and subsequent embryo development, mitochondria change their morphology by membrane fusion and fission, and coordinately undergo mult...
journal_title:Journal of biochemistry
pub_type: 杂志文章,评审
doi:10.1093/jb/mvz093
更新日期:2020-03-01 00:00:00
abstract::Upon CS2SO4 density-gradient equilibrium centrifugation, 60S subunits of rat liver ribosomes were dissociated to form three bands at the densities of 1.55, 1.40, and 1.30 g/ml. The bands at 1.55 and 1.30 g/ml were shown to contain exclusively RNA or proteins, respectively, whereas the band at 1.40 g/ml contained both ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a133504
更新日期:1981-08-01 00:00:00
abstract::Activation-induced cell death (AICD) plays a critical role in the maintenance of homeostasis and peripheral tolerance in the immune system, and is mediated by Fas ligand (FasL) expression and the interaction between Fas and FasL. In the present study, we examined the role of the ubiquitin-proteasome system in AICD usi...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a003106
更新日期:2002-03-01 00:00:00
abstract::The gene encoding subtilisin Amylosacchariticus from Bacillus subtilis var. amylosacchariticus was isolated and the entire nucleotide sequence of the coding sequence was determined. The deduced amino acid sequence revealed an N-terminal signal peptide and pro-peptide of 106 residues followed by the mature protein comp...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a122380
更新日期:1988-06-01 00:00:00