CONGENITAL GOITRE IN SHEEP: ISOLATION OF THE IODOPROTEINS WHICH REPLACE THYROGLOBULIN

1976 ◽  
Vol 71 (2) ◽  
pp. 179-192 ◽  
Author(s):  
C. E. DOLLING ◽  
B. F. GOOD

SUMMARY Immunological and chromatographic studies of proteins from the congenital goitre of South Australian Merino sheep revealed that normal thyroglobulin is absent from the thyroid glands of these sheep. However, a thyroglobulin-immunoreactive iodoprotein was isolated by affinity chromatography on agarose gel to which antibody against thyroglobulin had been covalently bound. Sucrose-gradient ultracentrifugation indicated that this iodoprotein had a sedimentation coefficient of 8S and a molecular weight of approximately 175000. This iodoprotein is therefore about one quarter the size of normal thyroglobulin (19S; 660000) and is similar in size to the subunit of thyroglobulin (3-8S; 165000) although this has usually been described as non-iodinated except when derived by reductive fission. In addition the goitre extract contained iodoproteins which had the immunological properties of serum albumin and immunoglobulin G. Determination of the iodine and iodoamino acid content of the hydrolysed iodoproteins revealed that they contained iodothyronines which were able to contribute to the production of thyroid hormones although the total iodothyronine content of the goitrous gland was less than that of the normal sheep thyroid gland.

1969 ◽  
Vol 24 (7) ◽  
pp. 885-893 ◽  
Author(s):  
Thérèse Coquerelle ◽  
Leuthold Bohne ◽  
Ulrich Hagen ◽  
Jürgen Merkwitz

DNA isolated from Coli bacteriophage T1 was irradiated in 0.165 ᴍ NaCl with γ-rays. The molecular weight was determined by measurement of the sedimentation coefficient and viscosity. An analysis of the boundary permits the determination of the sedimentation distribution. The distribution of sedimentation coefficients obtained at various DNA concentrations were extrapolated to zero concentration and were transformed into molecular weight distributions. These were used to calculate the weight average molecular weight Mw and the number average molecular weight Mn.The molecular weight of T1-DNA was found to be 32· 106. After irradiation at a concentration of 200 μg/ml, double breaks as well as intermolecular crosslinks could be determined. The number of double breaks showed a rise with dose that can best be described as composed of a linear and a quadratic term. At low doses the crosslinks increase linearly, the rate being approximately half of that for the linear part of the double breaks. After higher doses, where most of the molecules are degraded, apparently no additional crosslinks are produced. No crosslinks were seen in DNA degraded by DNase. The influence of the DNA concentration on the degradation and the formation of crosslinks is discussed.


1974 ◽  
Vol 29 (11-12) ◽  
pp. 661-666 ◽  
Author(s):  
Ernst Schulte ◽  
Werner Schloot ◽  
H. Werner Goedde

Abstract Human liver N-acetyltransferase was purified by means of column chromatography on Sephadex G-100 (18 fold; yield: 60-70%) and preparative disc electrophoresis (40 fold; yield: 95 - 100%). A separation of the hypothetical “serotonin-N-acetyltransferase” and “INH-N-acetyltransferase” on the basis of a possible difference of the charge of the proteins could not be achieved (disc electrophoresis). Thus the assumption is confirmed that INH and Serotonin are substrates of one enzyme. The activity of N-acetyltransferase can be stabilized by adding thioglycolate, 2-mercaptoethanol, and cysteine. In some cases an activation of 100 to 200% could be observed. A molecular weight of about 26 500 was determined by the method of column chromatography on Sephadex as well as by calculating the sedimentation coefficient. Enzymes prepared by different procedures showed similar Kм-values.


Parasitology ◽  
1992 ◽  
Vol 104 (1) ◽  
pp. 1-9 ◽  
Author(s):  
U. Kawazoe ◽  
F. M. Tomley ◽  
J. A. Frazier

SUMMARYSporozoites ofEimeria tenellawere disrupted by sonication and subcellular fractions were separated by sucrose gradient ultracentrifugation. Fractions from gradients were characterized by electron microscopical appearance and their polypeptide and antigenic profiles determined by PAGE and Western blotting with antisera to sporozoites and 1st- and 2nd-generation merozoites. Fractions containing micronemes, rhoptries or membranes showed markedly different polypeptide content and antigenic reactivity. Microneme epitopes were strongly conserved between sporozoites and 2nd-generation merozoites whereas the majority of rhoptry epitopes and many membrane epitopes were sporozoite specific. The only polypeptide of sporozoites which was strongly recognized by antisera raised to 1st generation merozoites was a microneme antigen of molecular weight approximately 100 kDa.


1979 ◽  
Vol 183 (2) ◽  
pp. 325-330 ◽  
Author(s):  
E Ilan ◽  
E Daniel

Haemoglobin from the tadpole shrimp, Lepidurus apus lubbocki, was found to have a sedimentation coefficient (s020,w) of 19.3 +/- 0.2 S and a molecular weight, as determined by sedimentation equilibrium, of 798000 +/- 20000. The amino acid composition showed the lack of cysteine and cystine residues. A haem content of 3.55 +/- 0.03% was determined, corresponding to a minimal mol.wt. of 17400 +/- 200. The pH-independence in the range pH 5-11 of the sedimentation coefficient indicates a relatively high stability of the native molecule. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis gave one band with mobility corresponding to a mol.wt. of 34000 +/- 1500. The molecular weight of the polypeptide chain was determined to be 32800 +/- 800 by sedimentation equilibrium in 6 M-guanidinium chloride and 0.1 M-2-mercaptoethanol. The findings indicate that Lepidurus haemoglobin is composed of 24 identical polypeptide chains, carrying two haem groups each.


1988 ◽  
Vol 106 (1) ◽  
pp. 133-140 ◽  
Author(s):  
G Piperno

This study of the axoneme led to the identification of a previously unknown adenosine triphosphatase (ATPase), which is likely a major component of inner dynein arms. The ATPase was isolated from a soluble fraction of axonemes obtained from pf 28, a Chlamydomonas mutant lacking the outer dynein arms. The activity hydrolyzed up to 2.3 mumol of ATP.min-1.mg-1 of protein (at pH 7.2, in the presence of both Ca++ and Mg++), had a sedimentation coefficient of 11S in sucrose gradient, and cosedimented with four polypeptides of apparent molecular weight 325,000, 315,000 140,000, and 42,000. Several arguments indicate that the new ATPase is a component of the inner dynein arms. Three or four polypeptides cosedimenting with the activity belong to a group of axonemal components that are deficient in the axonemes of pf 23 and pf 30, two mutants that display different levels of inner dynein arm deficiency. The 42,000 component is axonemal actin, a subunit of two other inner dynein ATPases. The two polypeptides of molecular weight greater than 300,000 have electrophoretic mobility similar to that of high molecular weight components of outer and inner dynein arms. In spite of some similarities each ATPase isolated from inner or outer arms is composed of a different set of polypeptides. Different ATPases may be required for the modulation of localized sliding of adjacent outer double microtubules in the axoneme.


1971 ◽  
Vol 26 (10) ◽  
pp. 1040-1044 ◽  
Author(s):  
Wolfram Gerlich

Gel chromatography with 6% agarose gel (Sepharose 6B) can be used for measuring the Stokes’ radius of biological particles within the range of 1,5 nm and 35 nm. The molecular weight determination of proteins is not very reliable with this method. Hepatitis sera have been chromatographied to measure the size of hepatitis associated antigen (Australia-antigen).The radius of this antigen was determined to be 10,3 nm, which agrees with the results of electron microscopy and ultracentrifugation. The Stokes’ radius of human serum IgM was found to be 10,6 nm.


1967 ◽  
Vol 18 (01/02) ◽  
pp. 089-100 ◽  
Author(s):  
J.-E Niléhn

SummaryEnd split products of fibrinogen after prolonged interaction with plasmin were separated on DEAE-cellulose. The D and E compounds measured with light ab- sorbancy constituted about 75% respectively 10% of the end split products.The D product was separated by electrophoresis into 8 components with slight difference in charge and all of them carried the same antigenic determinants. All components were found in plasmin digested fibrinogen prepared from a pool and from single donors. Four of the ∼D components were predominant. The sedimentation coefficient of the D preparation with these 4 components was 5.3 and the fraction sedimented as an homogenous peak. Slight heterogeneity of the preparation was, however, found on determination of the diffusion coefficient. The molecular weight was calculated as 80,000. On gel filtration of the D fraction on Sephadex G 200, the D products were eluted in the beginning of the albumin peak. It is suggested that the D product which is practically homogenous on ultracentrifugation dissociates on electrophoresis. The combination of the electrophoretic, immunologic and ultracentrifugal data suggests that the fibrinogen molecule consists of a series of similar repetitive units.The E product was homogenous in the ultracentrifuge and on electrophoresis. The sedimentation coefficient was 3.3 and the molecular weight was estimated to 40,800.On filtration through Sephadex G 200 the E product was hardly distinguishable from the D product and was eluted together with the ablumin.


1969 ◽  
Vol 113 (1) ◽  
pp. 131-138 ◽  
Author(s):  
U E Loening

1. The effects of changes in experimental conditions on the mobility of RNA in polyacrylamide-gel electrophoresis were investigated. 2. The linear relation between log(molecular weight) and electrophoretic mobility was shown to be independent within limits of salt or gel concentration. 3. The relative mobility of RNA with low content of guanylic acid and cytidylic acid residues was decreased in low-ionic-strength buffer. This was related to a small relative decrease in sedimentation coefficient. 4. However, Mg2+ ion caused almost no increase in mobility although it was associated with large increases in sedimentation coefficient. This suggested opposing actions of Mg2+ ion on the size and effective charge of the RNA. 5. It is concluded that the method provides a satisfactory measurement of molecular weight, which is almost independent of the nucleotide composition of RNA at moderate salt concentrations.


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