TWO-DIMENSIONAL NATIVE-SDS PAGE ANALYSIS OF MAIZE MALATE DEHYDROGENASE ISOZYMES: EVIDENCE FOR “SIZE ALLELES”

Author(s):  
Kathleen J. Newton ◽  
Drew Schwartz
1987 ◽  
Vol 88 (4) ◽  
pp. 453-466
Author(s):  
R.W. Linck ◽  
M.J. Goggin ◽  
J.M. Norrander ◽  
W. Steffen

Rabbit antibodies raised and purified against three tektins, proteins of flagellar doublet microtubules from sea-urchin sperm (Lytechinus pictus and Strongylocentrotus purpuratus), were used to study tektin biochemistry and their structural localization. Doublet microtubules were fractionated into tektin filaments and separated by SDS-PAGE into three major tektin polypeptide bands (Mr = 47, 51 and 55 (X 10(3)), which were used to immunize rabbits. Antibodies against each tektin (anti-tektins) were affinity-purified and then characterized by two-dimensional isoelectric focusing/SDS-PAGE immunoblotting and by immunofluorescence microscopy. In two-dimensional immunoblots of 0.5% Sarkosyl-resistant fractions of flagellar microtubules, the antibody against the 55 X 10(3) Mr tektin (anti-55) stained one major polypeptide of 55 X 10(3) Mr and pI 6.9, anti-51 stained two polypeptides of 51 X 10(3) Mr and pI approximately 6.15, and anti-47 stained one major polypeptide of 47 X 10(3) Mr and pI 6.15. The anti-tektins also stained several minor neighbouring polypeptides, which may be isoelectric variants, novel tektins or unrelated proteins. Furthermore, anti-47 crossreacted with the major 55 X 10(3) Mr polypeptide. By immunofluorescence microscopy all three anti-tektins stained methanol-fixed echinoderm sperm flagella and embryonic cilia. In addition, anti-47 and anti-55 stained unfixed, demembranated axonemes. Besides staining axonemes, all anti-tektins labelled the basal body region, and anti-51 labelled the sperm head envelope. These results indicate that the tektins are a complex family of proteins that are components of axonemal microtubules and possibly other cytoplasmic and nuclear structures.


2018 ◽  
Vol 22 (2) ◽  
pp. 57
Author(s):  
Ratih Asmana Ningrum ◽  
Widdya Kusuma Wardhani ◽  
Ike Wahyuni ◽  
Apon Zaenal Mustopa

     Recombinant Human Interferon Alpha-2a (rhIFNα-2a) is a therapeutic protein that used in hepatitis and cancer treatments. In our previous research, we developed higher molecular weight of the protein through human serum albumin fusion. The fusion and non fusion form of rhIFNα-2a were produced in Pichia pastoriswith 86 kDa and 19 kDa in size respectively. In previous research, protein yield was not reproducible due to unoptimized expression conditions. This reseach was aimed to optimize expression condition process and to characterize the fusion and non fusion forms of rhIFNα-2a. The parameters to observe in overproduction include nutrient (media and methanol concentration) and non nutrient (temperature andincubation period). Affinity and size exclusion cromatographicwere compared in protein purification. BCA assay was used to determine quantity of protein. Protein characterization was conducted using two-dimensional SDS PAGE and denaturation analyses. The optimal condition of expression was achieved using complex media with 1% of methanol for 3 day incubation period at 25°C. The protein yield was reproducible and higher comparing to previous research. Affinity chromatography resulted in higher purity of the proteins comparing to size exclusions. Characterization using two dimensional gel analysis revealed that isoelectric point of rhIFNα-2a is 6.5 for fusion form and 6.0 for non fusion form. The melting points of fusion protein were 56°C and 62°C whilst that of non fusion was 56°C.


1979 ◽  
Author(s):  
E.R. Podack ◽  
J.G. Curd ◽  
J.H. Griffin ◽  
H.J. Müller-Eberherd

S-protein (S) is a newly discovered 80,000 MW plosma glycoprotein. It functions as an inhibitor of the membrane attack complex of complement. We now wish to report that S also functions as thrombin protecting factor in coagulation; S forms a reversible complex with thrombin which is more resistant to inactivation by antithrombin III (AT III) than thrombin alone. An S-thrombin complex and on S-throm-bin-AT III complex were formed in clotted plasma and with isolated proteins as demonstrated by two dimensional Immunoelectrophoresis. Functional studies measuring the esterolytic or clotting activity of thrombin showed that S in the presence and absence of heparin decreased the rate of inactivation of thrombin by AT III. Similar results were observed using plasma. For example, in the presence of 0.04 u/ml heparin and 1.6 u/ml thrombin, the thrombin time of plasma depleted in S was 150 sec. as opposed to 15 sec. when the plasma was reconstituted with purified S. That this effect of S was due to a decreased inactivation of thrombin by AT III was demonstrated directly by SDS-PAGE analysis of plasma containing 125l-thrombin. In the presence of S the rate of formation of the 95,000 dalton 125I-thrombin-AT III complex was markedly decreased compared to the rate of complex formation in the S-depleted plasma. These data suggest that S may modulate the interactions of thrombin and AT III.


Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 496-500 ◽  
Author(s):  
M Wolf ◽  
C Boyer ◽  
A Tripodi ◽  
D Meyer ◽  
MJ Larrieu ◽  
...  

Abstract A qualitative defect of antithrombin III (AT III) has been demonstrated over three generations in eight members of an Italian family by the discrepancy between a normal amount of antigen and decreased antithrombin and anti-Xa activity in the presence or in the absence of heparin. By two-dimensional immunoelectrophoresis in the absence of heparin, two peaks of AT III were present in all patients' plasma. AT III was purified from normal and propositus plasma by sulfate dextran precipitation followed by heparin affinity chromatography. The elution profile of the patient's AT III was abnormal and allowed the separation of two populations of AT III, normal and abnormal. The first fraction (normal AT III) contained AT III activity, migrated as a single peak by two-dimensional immunoelectrophoresis and by sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE), demonstrated a single band with a molecular weight (mol wt) identical to that of normal AT III (60,000). Conversely, the last fraction, devoid of AT III activity, migrated as a single abnormal peak by two-dimensional immunoelectrophoresis in the absence of heparin. By SDS-PAGE, two bands were observed: one with a mol wt of 60,000 and a second one with a mol wt of 120,000. Western blots clearly demonstrated cross-reactivity of the 120,000 and 60,000 mol wt bands with monospecific antisera to human AT III. Reduction of the 120,000 mol wt band converted it to a single 60,000 mol wt band, suggesting the presence of an abnormal dimeric form of AT III. The name AT III Milano is proposed for this new variant.


1965 ◽  
Vol 13 (6) ◽  
pp. 510-514 ◽  
Author(s):  
JAMES L. CONKLIN ◽  
EDWARD J. NEBEL

Malate dehydrogenase fractions of the chick embryo were demonstrated after starch gel electrophoresis of homogenates of liver, brain and spleen. A total of seven malate dehydrogenase fractions were observed to occur in the chick embryo in an organ specific pattern. Treatment of the homogenates with urea, sodium chloride-sodium phosphate, and p-chloromercuribenzoate prior to electrophoresis revealed that only three distinct malate dehydrogenase-active proteins were presence. Two of these proteins exhibited properties similar to those previously reported for the supernatant malate dehydrogenase and mitochondrial malate dehydrogenase of other species. Becuase of the differing properties of chick malate and lactate dehydrogenase it is concluded that the molecular basis for malate dehydrogenase isozymes is different from that reported for lactate dehydrogenase isozymes.


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