scholarly journals Organospecific reactions of yellow lupin seedlings to lead

2014 ◽  
Vol 66 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Jarosław Gzyl ◽  
Roman Przymusiński ◽  
Adam Woźny

Changes caused by lead, supplied in the form of Pb(NO3)2, in roots and hypocotyls of 4 day old yellow lupin (<em>Lupinus luteus</em> L. cv. <em>ventus</em>) seedlings have been analyzed using a transmission electron microscope and polyacrylamide gel electrophoresis (PAGE). The cells of all examined parts of the roots growing in the presence of Pb<sup>2+</sup> contained many lead deposits (mainly in the cell walls and vacuoles) and the increased amount of polypeptides of molecular weight close to 16 kDa have been observed. Similar changes were detected in the area of hypocotyl adjoining the root. However, in upper regions of the hypocotyl only a slight amount of lead deposits was visible and the 16 kDa polypeptide content was comparable to the control cells. The obtained results indicate a relationship between the presence of lead deposits in cells and accumulation of polypeptides of - 16 kDa. The results seem also to indicate that in the analyzed parts of the seedlings, both the amount of accumulated polypeptides of MW - 16 kDa and the amount of lead decreased from root tip to hypocotyl.

1981 ◽  
Vol 197 (1) ◽  
pp. 171-175 ◽  
Author(s):  
J Yariv ◽  
A J Kalb ◽  
R Sperling ◽  
E R Bauminger ◽  
S G Cohen ◽  
...  

Bacterioferritin isolated from Escherichia coli is of two kinds: a protein containing a polynuclear iron compound, the bacterioferritin proper and a protein free of the polynuclear iron compound, the apo-bacterioferritin. Bacterioferritin of both kinds is characterized by absorption maxima at 417,530 and 560 nm, contributed by protohaem IX. Single crystals of bacterioferritin of the space group I432 suggest that the molecule is made up of 24 identical subunits related by a cubic point symmetry. The molecular weight of the protein subunit, as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, is 15000. In the electron microscope the bacterioferritin molecule appears to be a sphere of 9.5 nm (95 A) diameter composed of a negatively staining outer shell and an inner electron-dense core of 6 nm (60 A) diameter.


1972 ◽  
Vol 54 (2) ◽  
pp. 399-407 ◽  
Author(s):  
J. Ramus ◽  
S. T. Groves

The accumulation of sulfate-35S by Porphyridium aerugineum cells and subsequent appearance of solubilized capsular polysaccharide-35S in the growth medium were examined The uptake of label by the cells was largely light dependent. Pulse-chase experiments using log phase cells revealed a rapid labeling of solubilized capsular polysaccharide, recovered from the medium as the cetylpyridinium chloride precipitate Polyacrylamide gel electrophoresis of the polysaccharide-35S showed the sulfate to be firmly bound to an immobile fraction. Sephadex chromatography revealed the molecular weight of the polysaccharide to be in excess of 2 x 105. Acid hydrolysis of the polysaccharide-35S released sulfate-35S ion as evidenced by radioautography of thin layer chromatographs Preliminary electron microscope evidence suggests that the synthesis, movement, and deposition of the capsular polysaccharide on the cell surface are Golgi complex-mediated processes


1974 ◽  
Vol 15 (3) ◽  
pp. 495-511
Author(s):  
F. D. WARNER ◽  
I. MEZA

Microtubule protofilaments and their subunits isolated from sperm flagellar doublet tubules of the sea urchin Strongylocentrotus purpuratus were examined by analytical biochemistry and high-resolution negative staining electron microscopy. All microtubule (tubulin) fractions show 2 polypeptide bands (α and β tubulins) in an approximate 1:1 ratio on urea-polyacrylamide gel electrophoresis. Heat (37 °C)-solubilized microtubules yield a protein fraction containing the tubulin dimer of molecular weight 115000 Daltons. The dimeric tubulin subunit, as seen in the electron microscope, has an overall size of about 3.5 x 8 nm and appears to have the configuration of a figure 8 because of stain penetration into the centre of each of its 2 halves (figure os). Isolated protofilaments (3.5 ± 0.3 nm thick) can each be resolved into 2 subfilaments (1.7 ± 0.2 nm thick). The 2 subfilaments have periodic lateral associations resulting in the basic 4-nm subunit repeat (figure o) along the protofilament. Examination of collapsed and solubilizing protofilaments shows the figure 8 (dimeric) subunits separating at random along the protofilaments. We conclude that the tubulin dimer must be composed of either elongated or bilobed monomers which result in the figure 8 configuration and hence the 2-stranded appearance of the protofilaments.


1992 ◽  
Vol 68 (05) ◽  
pp. 534-538 ◽  
Author(s):  
Nobuhiko Yoshida ◽  
Shingi Imaoka ◽  
Hajime Hirata ◽  
Michio Matsuda ◽  
Shinji Asakura

SummaryCongenitally abnormal fibrinogen Osaka III with the replacement of γ Arg-275 by His was found in a 38-year-old female with no bleeding or thrombotic tendency. Release of fibrinopeptide(s) by thrombin or reptilase was normal, but her thrombin or reptilase time in the absence of calcium was markedly prolonged and the polymerization of preformed fibrin monomer which was prepared by the treatment of fibrinogen with thrombin or reptilase was also markedly defective. Propositus' fibrinogen had normal crosslinking abilities of α- and γ-chains. Analysis of fibrinogen chains on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the system of Laemmli only revealed the presence of abnormal γ-chain with an apparently higher molecular weight, the presence of which was more clearly detected with SDS-PAGE of fibrin monomer obtained by thrombin treatment. Purified fragment D1 of fibrinogen Osaka III also seemed to contain an apparently higher molecular weight fragment D1 γ remnant on Laemmli gels, which was digested faster than the normal control by plasmin in the presence of [ethy-lenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA).


1979 ◽  
Author(s):  
M Ribieto ◽  
J Elion ◽  
D Labie ◽  
F Josso

For the purification of the abnormal prothrombin (Pt Metz), advantage has been taken of the existence in the family of three siblings who, being double heterozygotes for Pt Metz and a hypoprothrombinemia, have no normal Pt. Purification procedures included barium citrate adsorption and chromatography on DEAE Sephadex as for normal Pt. As opposed to some other variants (Pt Barcelona and Madrid), Pt Metz elutes as a single symetrical peak. By SDS polyacrylamide gel electrophoresis, this material is homogeneous and appears to have the same molecular weight as normal Pt. Comigration of normal and abnormal Pt in the absence of SDS, shows a double band suggesting an abnormal charge for the variant. Pt Metz exhibits an identity reaction with the control by double immunodiffusion. Upon activation by factor Xa, Pt Metz can generate amydolytic activity on Bz-Phe-Val-Arg-pNa (S2160), but only a very low clotting activity. Clear abnormalities are observed in the cleavage pattern of Pt Metz when monitored by SDS gel electrophoresis. The main feature are the accumulation of prethrombin l (Pl) and the appearance of abnormal intermediates migrating faster than Pl.


1977 ◽  
Vol 55 (9) ◽  
pp. 958-964 ◽  
Author(s):  
M. P. C. Ip ◽  
R. J. Thibert ◽  
D. E. Schmidt Jr.

Cysteine-glutamate transaminase (cysteine aminotransferase; EC 2.6.1.3) has been purified 149-fold to an apparent homogeneity giving a specific activity of 2.09 IU per milligram of protein with an overall yield of 15%. The isolation procedures involve the preliminary separation of a crude rat liver homogenate which was submitted sequentially to ammonium sulfate fractionation, TEAE-cellulose column chromatography, ultrafiltration, and isoelectrofocusing. The final product was homogenous when examined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). A minimal molecular weight of 83 500 was determined by Sephadex gel chromatography. The molecular weight as estimated by polyacrylamide gel electrophoresis in the presence of SDS was 84 000. The purified enzyme exhibited a pH optimum at 8.2 with cysteine and α-ketoglutarate as substrates. The enzyme is inactivated slowly when kept frozen and is completely inactivated if left at room temperature for 1 h. The enzyme does not catalyze the transamination of α-methyl-DL-cysteine, which, when present to a final concentration of 10 mM, exhibits a 23.2% inhibition of transamination of 30 mM of cysteine. The mechanism apparently resembles that of aspartate-glutamate transaminase (EC 2.6.1.1) in which the presence of a labile hydrogen on the alpha-carbon in the substrate is one of the strict requirements.


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.


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