scholarly journals Purification and characterization of protein disulphide-isomerase from the unicellular green alga Chlamydomonas reinhardii. A 120 kDa dimer antigenically distinct from the vertebrate enzyme

1990 ◽  
Vol 268 (1) ◽  
pp. 63-68 ◽  
Author(s):  
D D Kaska ◽  
K I Kivirikko ◽  
R Myllylä
Keyword(s):  
Green Alga ◽  
Polyclonal Antibodies ◽  
Active Form ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Chlamydomonas Reinhardii ◽  
Protein Disulphide Isomerase ◽  
Unicellular Green Alga ◽  
A Subunit

Protein disulphide-isomerase (PDI) has been isolated from the unicellular green alga Chlamydomonas reinhardii and purified by (NH4)2SO4 precipitation, gel filtration and DEAE-Sephacel, hydroxyapatite and f.p.l.c. chromatography. The active algal enzyme is a 120 kDa dimer with a subunit molecular mass of 60 kDa when determined by SDS/PAGE. Although similar in size to the previously isolated vertebrate PDIs, the algal enzyme is antigenically distinct, polyclonal antibodies against the algal PDI showing no cross-reactivity with the vertebrate enzyme on immunoblots, and vice versa. The anti-(algal PDI) antiserum did not inhibit algal PDI activity, and C. reinhardii PDI could be immobilized on anti-PDI-Protein A-Sepharose in active form. In contrast with the situation in vertebrates, where PDI functions as a subunit of prolyl 4-hydroxylase, the C. reinhardii PDI is not associated with the algal prolyl 4-hydroxylase.

Purification of Tetragalloylglucose 4-O-Galloyltransferase and Preparation of Antibodies against This Key Enzyme in the Biosynthesis of Hydrolyzable Tannins

2000 ◽  
Vol 55 (7-8) ◽  
pp. 582-587 ◽  
Author(s):  
Petra Grundhöfer ◽  
Georg G. Gross
Keyword(s):  
Quercus Robur ◽  
Polyclonal Antibodies ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Pedunculate Oak ◽  
Hydrolyzable Tannins ◽  
Apparent Homogeneity ◽  
Key Enzyme ◽  
Rhus Typhina

Abstract The enzyme, β-glucogallin: 1,2,3,6-tetra-O-galloyl- β-ᴅ-glucose 4-O-galloyltransferase, which catalyzes the last common step in the biosynthesis of the two subclasses of hydrolyzable tannins, i.e. gallotannins and ellagitannins, was purified 868-fold from leaves of pedunculate oak ( Quercus robur, syn. Q. pedunculata) to apparent homogeneity. Polyclonal antibodies against this pivotal enzyme were raised in rabbits and purified by protein-A chromatography, gel-filtration and affinity complexation. They were found to react specifically with acyltransferase from oak, displaying no cross-reactivity towards analogous enzymes from other plants synthesizing hydrolyzable tannins along the same biogenetic route, e.g. Rhus typhina or Tellima grandiflora.

scholarly journals Characterization of a low-relative-molecular-mass prolyl 4-hydroxylase from the green alga Chlamydomonas reinhardii

1987 ◽  
Vol 241 (2) ◽  
pp. 483-490 ◽  
Author(s):  
D D Kaska ◽  
V Günzler ◽  
K I Kivirikko ◽  
R Myllylä
Keyword(s):  
Cell Wall ◽  
Green Alga ◽  
Gel Filtration ◽  
Relative Molecular Mass ◽  
Higher Plant ◽  
Chlamydomonas Reinhardii ◽  
Unicellular Green Alga ◽  
Plant Enzymes ◽  
Inhibition Studies

Prolyl 4-hydroxylase was partially purified and characterized from the unicellular green alga, Chlamydomonas reinhardii. This enzyme differed from all the animal and plant prolyl 4-hydroxylases studied so far in that its Mr was only about 40,000 by gel filtration, being thus less than one-sixth of those determined for the vertebrate and higher-plant enzymes. The algal enzyme did not hydroxylate to any significant extent chick-embryo protocollagen or triple-helical (Pro-Pro-Gly)10, whereas a low hydroxylation rate was found with denatured (Pro-Pro-Gly)10. Poly(L-proline), which is an effective inhibitor of the vertebrate enzymes but acts as a substrate for some higher-plant enzymes, was a good substrate. In the absence of poly(L-proline) the enzyme catalysed an uncoupled decarboxylation of 2-oxoglutarate. Studies of the Km values for the co-substrates and cofactors and the specificity of the 2-oxoglutarate requirement, as well as inhibition studies with selected 2-oxoglutarate analogues, suggested that the catalytic site of the algal enzyme is similar to, but not identical with, those of the vertebrate enzymes. The existence of distinct similarities was further demonstrated by an inhibition of the algal enzyme activity with a monoclonal antibody to the beta-subunit of human prolyl 4-hydroxylase. The amount of prolyl 4-hydroxylase activity in the algal cells was not altered by signals which recognize the presence or absence of the cell wall, as determined in studies on experimental cell-wall regeneration and wall-less mutants.

scholarly journals Molecular Distinction of Circulating Pregnancy-Associated Plasma Protein A in Myocardial Infarction and Pregnancy

2005 ◽  
Vol 51 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Qiu-Ping Qin ◽  
Saara Kokkala ◽  
Juha Lund ◽  
Natalia Tamm ◽  
Liisa-Maria Voipio-Pulkki ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Pregnant Women ◽  
Molecular Mass ◽  
Plasma Protein ◽  
Specific Antibody ◽  
Protein A ◽  
Gel Filtration ◽  
Single Peak ◽  
Serum Samples ◽  
A Subunit

Abstract Background: In the blood of pregnant women, pregnancy-associated plasma protein A (PAPP-A) is present as a covalent complex with the proform of eosinophil major basic protein (proMBP). Recently, increased serum concentrations of PAPP-A have been found in acute coronary syndromes (ACS). The aim of this study was to investigate whether the circulating PAPP-A in ACS is the same as that in pregnancy. Methods: We developed two time-resolved immunofluorometric assays based on a relative epitope map constructed by the use of 17 monoclonal antibodies. One assay, which measured total PAPP-A, used two PAPP-A subunit-specific antibodies. The other assay, which measured PAPP-A/proMBP complex, used one proMBP subunit-specific antibody and one PAPP-A subunit-specific antibody. Serum samples from four patients with myocardial infarction (MI), three pregnant women in their first trimester, and one in her third trimester were fractionated by gel filtration on a Superose™ 6 precision column. The two assays were used to analyze fractions obtained by gel filtration as well as serum samples serially collected from four other MI patients. Results: Pregnancy-related PAPP-A was eluted as a single peak with a molecular mass of ∼700 kDa, whereas ACS-related PAPP-A was also eluted as a single peak but with a molecular mass of ∼530 kDa. Pregnancy-related PAPP-A was detected equally by the two assays, whereas increased ACS-related PAPP-A was detected only by the assay for total PAPP-A. Conclusions: Our results provide the first evidence that circulating ACS-related PAPP-A is different from circulating pregnancy-related PAPP-A in that it is not complexed with proMBP. These findings provide a solid foundation for the design of immunoassays to accurately measure atherosclerosis-associated plasma protein A in the circulation.

scholarly journals The induction of secondary cytolytic T lymphocytes by solubilized membrane proteins.

1978 ◽  
Vol 147 (3) ◽  
pp. 946-951 ◽  
Author(s):  
M Mescher ◽  
L Sherman ◽  
F Lemonnier ◽  
S Burakoff
Keyword(s):  
Plasma Membranes ◽  
Active Form ◽  
Protein A ◽  
Gel Filtration ◽  
Biologically Active ◽  
Cytolytic T Lymphocytes ◽  
Histocompatibility Complex ◽  
Cell Plasma ◽  
Immunological Specificity ◽  
Membrane Bound

Membrane-bound antigens responsible for induction of a secondary allogeneic murine cytolytic T-cell (CTL) response have been obtained in a soluble, biologically active form by deoxycholate solubilization of tumor cell plasma membranes. The active proteins are soluble by the criteria of both ultracentrifugation and gel filtration. The immunological specificity of the induced CTL and removal of the activity from solution by treatment with B6 anti-P815 (anti-H-2d) antiserum and Protein A-Sepharose demonstrate that the CTL-inducing activity is dependent upon solubilized major histocompatibility complex antigens.

scholarly journals Macroprolactinemia: Diagnostic, Clinical, and Pathogenic Significance

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Akira Shimatsu ◽  
Naoki Hattori
Keyword(s):  
Middle Age ◽  
Molecular Form ◽  
Protein A ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Precipitation Method ◽  
Binding Studies ◽  
Rat Pituitary ◽  
Peg Precipitation Method

Macroprolactinemia is characterized by a large molecular mass of PRL (macroprolactin) as the main molecular form of PRL in sera, the frequent elevation of serum PRL (hyperprolactinemia), and the lack of symptoms. Macroprolactin is largely a complex of PRL with immunoglobulin G (IgG), especially anti-PRL autoantibodies. The prevalence of macroprolactinemia is 10–25% in patients with hyperprolactinemia and 3.7% in general population. There is no gender difference and a long-term followup demonstrates that macroprolactinemia develops before middle age and is likely a chronic condition. Polyethylene-glycol- (PEG-) precipitation method is widely used for screening macroprolactinemia, and gel filtration chromatography, protein A/G column, andI125-PRL binding studies are performed to confirm and clarify its nature. The cross-reactivity of macroprolactin varies widely according to the immunoassay systems. The epitope on PRL molecule recognized by the autoantibodies is located close to the binding site for PRL receptors, which may explain that macroprolactin has a lower biological activity. Hyperprolactinemia frequently seen in macroprolactinemic patients is due to the delayed clearance of autoantibody-bound PRL. When rats are immunized with rat pituitary PRL, anti-PRL autoantibodies are produced and hyperprolactinemia develops, mimicking macroprolactinemia in humans. Screening of macroprolactinemia is important for the differential diagnosis of hyperprolactinemia to avoid unnecessary examinations and treatments.

scholarly journals Structural comparison of two esterases from Drosophila mojavensis isolated by immunoaffinity chromatography

1986 ◽  
Vol 238 (3) ◽  
pp. 691-699 ◽  
Author(s):  
J Pen ◽  
J Van Beeumen ◽  
J J Beintema
Keyword(s):  
Gel Electrophoresis ◽  
High Efficiency ◽  
Polyacrylamide Gel Electrophoresis ◽  
Protein A ◽  
Gel Filtration ◽  
Immunoaffinity Chromatography ◽  
Cross Reactivity ◽  
Drosophila Mojavensis ◽  
Structural Comparison ◽  
Final Purification

Antibodies raised against esterase-4 and esterase-5 from Drosophila mojavensis were coupled to Protein A-Sepharose CL-4B to prepare high-efficiency immunomatrices used for their purification. Final purification was achieved by anion-exchange h.p.l.c., in the case of esterase-5 followed by gel-filtration h.p.l.c. The resultant esterase preparations were homogeneous, as judged by gel-filtration h.p.l.c., SDS/polyacrylamide-gel electrophoresis and non-denaturing gel electrophoresis. Esterase-4 and esterase-5 are the products of a duplicated gene. They are differently localized in the insect's body and expressed in different periods during development. Although both enzymes exhibit little immunological cross-reactivity, their amino acid compositions show few significant differences and their N-terminal sequences are largely identical, which clearly show their common origin.

scholarly journals Purification and characterization of cytosolic aldolase from carrot storage root

1990 ◽  
Vol 269 (1) ◽  
pp. 133-139 ◽  
Author(s):  
G B Moorhead ◽  
W C Plaxton
Keyword(s):  
Specific Activity ◽  
Polyclonal Antibodies ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Storage Roots ◽  
Carrot Root ◽  
Daucus Carota L ◽  
Native Molecular Mass ◽  
Spinach Leaf ◽  
Protein Staining

A single fructose-1,6-bisphosphate (FBP) aldolase has been detected in extracts from carrot storage roots (Daucus carota L.). The enzyme was purified 850-fold to electrophoretic homogeneity and a final specific activity of 26.3 mumols of FBP utilized/min per mg of protein. SDS/PAGE of the final preparation revealed a single protein-staining band of 40 kDa. The native molecular mass was determined by analytical gel filtration to be 159 kDa, indicating that the enzyme is a homotetramer. Denaturing isoelectric focusing revealed two predominant protein-staining bands, with pI values of 5.6 and 5.7. The enzyme is a class I aldolase, since EDTA or metal ions had no effect on its activity. The enzyme was relatively heat-stable, had an activation energy (Ea) of 68.3 kJ.mol-1, and had an absorption coefficient of 8.08 x 10(4) M-1.cm-1 at 280 nm. Km values for FBP and sedoheptulose 1,7-bisphosphate (SBP) were both determined to be 6 microM (pH optima 7.4). The specificity constant with FBP was 2.6 times that obtained with SBP. Ribose 5-phosphate, 6-phosphogluconate, MgAMP, glucose 1-phosphate and phosphoenolpyruvate (PEP) were inhibitors. PEP was a mixed-type inhibitor with respect to FBP (Ki = 3.2 mM, K′i = 5.1 mM). No activators were found. Rabbit anti-(carrot aldolase) polyclonal antibodies immunoprecipitated the activity of both carrot root aldolase and spinach leaf cytosolic aldolase, but not that of spinach leaf plastid aldolase. Western-blot analysis also revealed cross-reactivity with cytosolic, but not plastid, spinach leaf aldolase, indicating that the single carrot root aldolase is cytosolic.

scholarly journals IMMUNOLOGICAL COMPARISON OF PECTINESTERASE ISOENZYMES FROM TOMATO

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1085e-1085
Author(s):  
Floyd M. Woods ◽  
Russell Pressey
Keyword(s):  
Polyclonal Antibodies ◽  
Tomato Fruit ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Cherry Tomato ◽  
Ripe Fruit ◽  
Molecular Weights ◽  
Cation Exchangers ◽  
Immunological Comparison ◽  
Tomato Cultivars

Pectinesterase is present in green tomato fruit and increases several-fold during ripening. Several isoenzymes of pectinesterase can be separated by chromatography of tomato extracts on DEAE-Sephadex A-50. The predominant isoenzyme in most tomato cultivars including Better Boy has been designated PE IV. This isoenzyme accounts for most of the increase in total pectinesterase during ripening of these cultivars. The fruit of some cherry tomato cultivars such as Pixie and Short Red contain some PE IV, but the major isoenzyme is PE III which occurs only in these cultivars. PE III and PE IV were isolated from ripe fruit of Short Red and Better Boy, respectively, to further characterize differences between the isoenzymes. PE III binds more strongly to cation exchangers, indicating that it is more basic than PE IV, The molecular weights were estimated by gel filtration to be 26,900 and 25, 100 for PE III and PE IV, respectively. Polyclonal antibodies were raised against the two enzymes. Cross reactivity of the enzymes with the antibodies indicates that PE III and PE IV are immunologically identical.

scholarly journals Detection of Aspergillus Flavus in Wheat Grains Using Anti-Mannoprotein (MP1) and Spore Proteins Polyclonal Antibodies

2021 ◽  
Author(s):  
Ranjana Kumari ◽  
Ananta Ghosh
Keyword(s):  
Aspergillus Flavus ◽  
Polyclonal Antibodies ◽  
Protein A ◽  
Fungal Species ◽  
Cross Reactivity ◽  
Soluble Form ◽  
Minimum Concentration ◽  
Wheat Grains ◽  
Stored Wheat ◽  
Spore Proteins

Abstract Cell wall mannoprotein (MP1) gene of an aflatoxigenic strain of Aspergillus flavus, isolated from stored wheat grains, was cloned and sequenced. MP1 protein was expressed in E. coli in soluble form and purified. Polyclonal antibodies were raised against recombinant MP1 protein and inactivated spores of this fungus in rabbit, and purified by ammonium sulphate precipitation, Protein A sepharose and antigen affinity chromatography. The minimum concentration of purified mycelial or spore proteins that could be detected by ELISA was determined as 100 ng using 2 µg of these antibodies. The anti-MP1 antibody was found more sensitive than anti-spore protein antibody. Western blot and immunofluorescence analysis showed reactivity of these antibodies to various proteins (30 kDa to 200 kDa) distributed throughout the surface of mycelia and spore of A. flavus. Cross reactivity of these antibodies was detected with fungi belonging to different Aspergillus, Rhizopus and Alternaria species out of fourteen different fungal species tested. In fungal contaminated wheat grains these antibodies could detect presence of as low as 1 µg mycelia or 103 spores per gram of wheat grains using ELISA. The results suggest that the developed antibodies could be successfully applied for the detection of predominant fungal infestation in stored wheat grains.

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