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

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.

1985 ◽  
Vol 108 (2) ◽  
pp. 284-288
Author(s):  
Abdul Waheed ◽  
Stephen J. Winters ◽  
George M. Farrow ◽  
Hiroyuki Oshima ◽  
Philip Troen

Abstract. Human testosterone-oestradiol-binding globulin (hTeBG) was purified from pregnancy serum by ammonium sulphate precipitation, preparative flatbed electrofocussing, Concanavalin A-Sepharose affinity chromatography, Sephadex G-150 gel filtration, DEAE-Sephadex chromatography and preparative polyacrylamide gel electrophoresis. The yield was 0.3 mg of hTeBG with a specific acitivity of 1.1 nmoles DHT bound per mg. An antiserum to TeBG was raised in rabbits. Anti-hTeBG IgG was separated from rabbit TeBG by DEAE-Affi-Gel-Blue chromatography. Anti-hTeBG was titrated using protein A-Sepharose which quantitatively binds IgG and therefore bound [3H]DHT-hTeBG-anti-TeBG complexes. The androgen binding components from human testis were separated on Concanavalin A-Sepharose columns into excluded and retained fractions. The antibody bound both testis fractions with titration curves which paralleled that of TeBG, indicating that these androphilic proteins share common immunodeterminants with hTe-BG. The possibility that these testicular proteins are identical in amino acid sequence to TeBG and differ only in carbohydrate content will require further verification. Finally, these results indicate that antibodies to TeBG can be used to study human testicular androgen-binding protein.


1986 ◽  
Vol 235 (1) ◽  
pp. 81-85 ◽  
Author(s):  
S K Ghosh ◽  
N K Mukhopadhyay ◽  
S Majumder ◽  
S K Bose

The final purification of the three-fraction enzyme complex mycobacillin synthetase was done by hydroxyapatite column chromatography and sucrose-density-gradient centrifugation; each of the fractions obtained migrates as a single component in SDS/polyacrylamide-gel electrophoresis and gel electrofocusing. The Mr of the enzyme fractions A, B and C by gel filtration is 260 000, 190 000 and 105 000, and that by SDS/polyacrylamide-gel electrophoresis is 252 000, 198 000 and 108 000 respectively. None of the enzyme fractions appears to possess subunit structure.


1992 ◽  
Vol 38 (5) ◽  
pp. 436-442 ◽  
Author(s):  
Devyani Dey ◽  
Jyoti Hinge ◽  
Abhay Shendye ◽  
Mala Rao

An alkalophilic thermophilic Bacillus sp. (NCIM 59) isolated from soil produced two types of cellulase-free xylanase at pH 10 and 50 °C. The two enzymes (xylanase I and II) were purified to homogeneity by ethanol precipitation followed by Bio-Gel P-10 gel filtration and preparative polyacrylamide gel electrophoresis. The molecular weights of xylanase I and II were estimated to be 35 000 and 15 800, respectively, by sodium dodecyl sulfate gel electrophoresis. The enzymes exhibited immunological cross-reactivity and were glycoproteins. They had similar temperature (50–60 °C) and pH (6) optima. Both xylanases were stable at 50 °C at pH 7 for 4 days. However, xylanase I was comparatively more stable than xylanase II at 60 °C. The isoelectric points of xylanase I and II were 4 and 8, respectively. The apparent Km values, using xylan as substrate, were 1.58 and 3.5 mg/mL, and Vmax values were 0.0172 and 0.742 μmol∙min−1∙mg−1, respectively. Both xylanases were inhibited by N-bromosuccinimide, suggesting the involvement of tryptophan in the active site. The hydrolysis patterns demonstrated that the xylanases were endoenzymes. Xylanase I and II yielded mainly xylobiose, xylotriose, and higher xylooligosaccharides, with traces of xylose from xylan. Key words: cellulase-free xylanase, alkalophilic thermophilic Bacillus sp., enzyme purification, characterization.


1997 ◽  
Vol 71 (2) ◽  
pp. 151-160 ◽  
Author(s):  
R.R. Hamed ◽  
T.M. Maharem ◽  
A.S. El-Guindy

AbstractDifferent types of proteoglycans (PGs) from adult worms of Schistosoma haematobium, were sequentially extracted using chaotropic agents under associative conditions (0.5 M GnCl), dissociative conditions (4 M GnCl) and detergents (Triton X-100 and SDS). The extracts were designated Fl, F2, F3 and F4, respectively. The highest amount of uronic acid and carbohydrate was detected in the associative extract (Fl) while the highest amount of protein was detected in the SDS extract (F4). Agarose polyacrylamide gel electrophoresis (A-PAGE) indicated the presence of a different PG in each extract with different electrophoretic mobilities. Agarose gel electrophoresis of glycosaminoglycan (GAG) separated from GnCl, associative and dissociative extracts, and the residue suggested the presence of dermatan sulphate in the two extracts and the residue, in addition to a GAG-like material found in the associative extract only. This glycosaminoglycan showed resistance to digestion with all mucopolysaccharidases and nitrous acid treatment. Gel filtration chromatography of associative extract on Sepharose CL-6B indicated the presence of three main uronic acid peaks (P1, P2 and P3). Chondroitin sulphate was the main GAG that could be detected in peak one (P1). Peak two (P2) contains carbohydrate and uronic acid but has no protein or absorbance at 280 nm. P2 has two types of GAGs: dermatan sulphate and a GAG-like material. The role of this PG in helping the adult schistosomes in evading immobilization by the host blood clotting cascade is discussed. Antibodies to peak one and peak two were detected in hamster sera infected with S. haematobium and S. mansoni using the ELISA test. The specificity of peak two was found to be evident in its low cross-reactivity (18.9%) when confronted with S. mansoni infected sera.


1974 ◽  
Vol 31 (01) ◽  
pp. 072-085 ◽  
Author(s):  
M Kopitar ◽  
M Stegnar ◽  
B Accetto ◽  
D Lebez

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.


Parasitology ◽  
1984 ◽  
Vol 88 (1) ◽  
pp. 27-36 ◽  
Author(s):  
R. J. Howard ◽  
J. W. Barnwell

SUMMARYPlasmodium knowlesi malaria-infected erythrocytes were radio-iodinated and several non-ionic, anionic and zwitterionic detergents were compared in their capacity to extract the labelled membrane proteins. The use of these detergents for antigen identification was tested by immunoprecipitation, after addition of Triton X-100 to some detergent extracts, using hyperimmune monkey antiserum and protein A-Sepharose. 125I-labelled antigens were specifically immunoprecipitated with all detergents tested, including the anionic detergents sodium dodecyl sulphate (SDS), deoxycholate and cholate; the zwitterions Zwittergent-312 and -314, CHAPS and Empigen BB, as well as several non-ionic detergents. The SDS-polyacrylamide gel electrophoresis patterns of 125I-labelled antigens varied after extraction with different detergents, there being no consistent pattern for detergents of a particular class. A total of 14 125I-labelled antigens were identified, 11 of them using Triton X-100. Some minor antigens identified with Triton X-100 were immunoprecipitated in greater amount after extraction in other detergents. Most importantly, two antigens Mr 200000 and 180000 were detected only after extraction with deoxycholate or SDS.


1988 ◽  
Vol 254 (2) ◽  
pp. 419-426 ◽  
Author(s):  
P M Wiest ◽  
E J Tisdale ◽  
W L Roberts ◽  
T L Rosenberry ◽  
A A F Mahmoud ◽  
...  

Biosynthetic labelling experiments with cercariae and schistosomula of the multicellular parasitic trematode Schistosoma mansoni were performed to determine whether [3H]palmitate or [3H]ethanolamine was incorporated into proteins. Parasites incorporated [3H]palmitate into numerous proteins, as judged by SDS/polyacrylamide-gel electrophoresis and fluorography. The radiolabel was resistant to extraction with chloroform, but sensitive to alkaline hydrolysis, indicating the presence of an ester bond. Further investigation of the major 22 kDa [3H]palmitate-labelled species showed that the label could be recovered in a Pronase fragment which bound detergent and had an apparent molecular mass of 1200 Da as determined by gel filtration on Sephadex LH-20. Schistosomula incubated with [3H]ethanolamine for up to 24 h incorporated this precursor into several proteins; labelled Pronase fragments recovered from the three most intensely labelled proteins were hydrophilic and had a molecular mass of approx. 200 Da. Furthermore, reductive methylation of such fragments showed that the [3H]ethanolamine bears a free amino group, indicating the lack of an amide linkage. We also evaluated the effect of phosphatidylinositol-specific phospholipase C from Staphylococcus aureus: [3H]palmitate-labelled proteins of schistosomula and surface-iodinated proteins were resistant to hydrolysis with this enzyme. In conclusion, [3H]palmitate and [3H]ethanolamine are incorporated into distinct proteins of cercariae and schistosomula which do not bear glycophospholipid anchors. The [3H]ethanolamine-labelled proteins represent a novel variety of protein modification.


1981 ◽  
Vol 197 (3) ◽  
pp. 629-636 ◽  
Author(s):  
J L McKenzie ◽  
A K Allen ◽  
J W Fabre

Human and canine brain Thy-1 antigens were solubilized in deoxycholate and antigen activity was followed both by conventional absorbed anti-brain xenosera of proven specificity and by mouse monoclonal antibodies to canine and human Thy-1. It is shown that greater than 80% of Thy-1 activity in the dog and man binds to lentil lectin, that the mobility on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of canine and human Thy-1 is identical with that of rat Thy-1 and that the Stokes radius in deoxycholate of canine and human brain Thy-1 is 3.0 nm and 3.25 nm respectively. Both lentil lectin affinity chromatography followed by gel-filtration chromatography on the one hand and monoclonal antibody affinity chromatography on the other gave high degrees of purification of the brain Thy-1 molecule in the dog and man, resulting in single bands staining for both protein and carbohydrate on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (except for a slight contaminant of higher molecular weight staining for protein but not carbohydrate with human Thy-1 purified by lentil lectin and gel-filtration chromatography). Analysis of canine and human brain Thy-1 purified by monoclonal antibody affinity chromatography with additional gel filtration through Sephadex G-200 showed that these molecules had respectively 38% and 36% carbohydrate. The amino acid and carbohydrate compositions were similar to those previously reported for Thy-1 of the rat and mouse, the main point of interest being the presence in canine and human brain Thy-1 of N-acetylgalactosamine, which has been reported in rat and mouse brain Thy-1 but not in Thy-1 from other tissues.


1980 ◽  
Vol 191 (3) ◽  
pp. 799-809 ◽  
Author(s):  
R G Sutcliffe ◽  
B M Kukulska-Langlands ◽  
J R Coggins ◽  
J B Hunter ◽  
C H Gore

Pregnancy-associated plasma protein-A (PAPP-A) has been purified by a combination of methods including antibody-affinity chromatography. The resultant protein, obtained in 16% yield from maternal serum, appeared as a single major component on non-denaturing polyacrylamide and SDS/polyacrylamide gel electrophoresis. The protein showed a single component when analysed by isoelectric focusing under denaturing conditions in the presence and absence of reduction and had a pI of 4.34 and 4.42 respectively. These pI values were indistinguishable from those of alpha 2-macroglobulin (alpha 2M). The molecular weight of the PAPP-A polypeptide as shown by SDS/polyacrylamide-gel electrophoresis was 187000, with a minor component of mol.wt. 82500 that was attributed to proteolysis. Since native PAPP-A had a molecular weight on gel chromatography very similar to that of alpha 2M (620000–820000), it was concluded that PAPP-A was a homotetramer. In the absence of reduction, a high-molecular-weight (420000) protomer of PAPP-A was found. It was deduced that PAPP-A, like alpha 2M, is a dinner, whose protomers are composed of disulphide-linked polypeptide chains. It was found that the molecular weight of the PAPP-A polypeptide exceeded that of alpha 2M by 3.3%, but that the total carbohydrate content of PAPP-A exceeded that of alpha 2M by 10% and that its neutral carbohydrate content exceeded that of alpha 2M by between 7.4 and 9.0%. The significance of the estimated molecular weights of alpha 2M (181000) and its major tryptic fragments is discussed in the light of published values. A tryptic fragment alpha 2M (82500 mol.wt.) was apparently the same size as the major tryptic fragment of PAPP-A.


1982 ◽  
Vol 152 (2) ◽  
pp. 687-691
Author(s):  
T H Watts ◽  
E A Worobec ◽  
W Paranchych

The proteins of purified inner and outer membranes obtained from Pseudomonas aeruginosa strains PAK and PAK/2Pfs were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose, and treated with antiserum raised against pure pili. Bound antipilus antibodies were visualized by reaction with 125I-labeled protein A from Staphylococcus aureus. The results showed that there are pools of pilin in both the inner and outer membranes of P. aeruginosa and that the pool size in the multipiliated strain is comparable with that of the wild-type strain.


Sign in / Sign up

Export Citation Format

Share Document