A comparison of certain isozyme patterns in lobeless and normal embryos of the snail, Ilyanassa obsoleta

Development ◽  
1971 ◽  
Vol 26 (3) ◽  
pp. 339-349
Author(s):  
Sallie B. Freeman

A study was made of the emergence of certain enzymes during the embryogenesis of Ilyanassa. Lobeless and normal embryos were compared in order to determine the effect of polar lobe removal on subsequent molecular developments. Polyacrylamide gel electrophoresis in capillary tubes, a technique requiring only small numbers of embryos, was used to obtain the isozyme patterns of alkaline phosphatases and of esterases. It was found that lobe removal interfered with the emergence of normal isozyme patterns of alkaline phosphatase and esterase during development. Certain bands of enzyme activity were severely reduced or absent while others appeared to be normal. The results provide further evidence that the influence of the polar lobe on development is of a specific nature.

1975 ◽  
Vol 147 (2) ◽  
pp. 205-214 ◽  
Author(s):  
E D Adamson ◽  
S E Ayers ◽  
Z A Deussen ◽  
C F Graham

The solubilization of 80% of the acetylcholinesterase activity of mouse brain was performed by repeated 2h incubations of homogenates at 37 degrees C in an aqueous medium. Analysis of the soluble extract by gel filtration on Sephadex G-200 showed that up to 80% of the enzyme activity was eluted in a peak which was estimated to consist of molecules of about 74000mol.wt. This peak was called the monomer form of the enzyme. After 3 days at 4 degrees C, the soluble extract was re-analysed and was eluted from the column in four peaks of about 74000, 155000, 360000 and 720000 mol.wt. Since the total activity of the enzyme in these peaks was the same as that in the predominantly monomer elution profile of fresh enzyme, we concluded that the monomer had aggregated, possibly into dimers, tetramers and octomers. Extracts of the enzyme were analysed by polyacrylamide-gel electrophoresis and the resulting multiple bands of enzyme activity on gels were shown to separate according to their molecular sizes, that is by molecular sieving. All these forms had similar susceptibilities to the inhibitors eserine, tetra-isopropyl pyrophosphoramide and compound BW 284c51 [1,5-bis-(4-allyldimethylammoniumphenyl)pentan-3-one dibromide]. Thus the forms of the enzyme in mouse brain which can be detected by gel filtration and polyacrylamide-gel electrophoresis may all be related to a single low-molecular-weight form which aggregates during storage. This supports similar suggestions made for the enzyme in other locations.


1975 ◽  
Vol 149 (3) ◽  
pp. 609-617 ◽  
Author(s):  
J Dunkerton ◽  
S P James

1. 2-Oxoaldehyde dehydrogenase was purified from sheep liver and gave one band on polyacrylamide-gel electrophoresis. 2. The enzyme was completely dependent for its activity on the presence of Tris or one of a number of related amines, all of general structure: (See article). When more than one R group was hydrogen no enzyme activity was observed. 3. Only one of these amines is known to exist in living tissues and large concentrations of all amines were required for maximum activity. L-2-Aminopropan-1-ol was the most effective amine on the basis of substrate Km and Vmax. values and the amine Km values. 4. The enzyme was activated by phosphate which lowered the Km values for methylglyoxal, amine and NAD+. 5. The pH optimum of the enzyme was 9.3 and there was no activity at pH values below 7.8. A search for activators that might produce activity at pH 7.4 proved unsuccessful. 6. The enzyme was inhibited by rather large concentrations of barbiturates (6-46 mM) and nitro-alcohol analogues of the activating amines (66-139 mM).


1979 ◽  
Vol 177 (1) ◽  
pp. 107-114 ◽  
Author(s):  
T G Villa ◽  
V Notario ◽  
J R Villanueva

The endo-1,3-beta-glucanase (EC 3.2.1.6) secreted into the culture medium by cells of Candida utilis was isolated and purified to homogeneity on polyacrylamide-gel electrophoresis and in ultracentrifugation studies (s20,w = 1.97S). The purified enzyme represented only 0.001% of the total 1,3-beta-glucanase activity, the remainder being due to an exo-1,3-beta-glucanase enzyme, and behaved as an acidic glycoprotein (pI 3.3) in isoelectric-focusing experiments. The mol.wt. was estimated to be 21 000 by gel filtration and polyacrylamide-gel electrophoresis. Studies on the hydrolysis of different substrates showed that the enzyme was only able to break down (1 leads to 3)-beta-linkages, by an endo-splitting mechanism. Glucono-delta-lactone, D-glucoronolactone and heavy metal ions such as Hg2+ were inhibitors of the enzyme activity. The function of this endo-beta-glucanase in C. utilis is discussed.


Author(s):  
TJ Brooks ◽  
HG Sammons

Loss of activity of the isoenzymes of γ-glutamyl transferase and alkaline phosphatase has been shown to occur during electrophoresis on polyacrylamide gel. After studying the possible factors concerned in this loss, reasonable recovery from the gel can be obtained only for the isoenzyme staying at the origin. Maximum recovery is 60% for origin γ-glutamyl transferase and 92% for origin alkaline phosphatase.


1979 ◽  
Vol 177 (1) ◽  
pp. 49-62 ◽  
Author(s):  
C M Clarke ◽  
B S Hartley

The restriction endonuclease BstI was purified from 70kg of Bacillus stearothermophilus. The final product is at least 97% pure as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis; this major protein species co-migrates with the enzyme activity on native polyacrylamide-gel electrophoresis and isoelectric focusing. Pure restriction endonuclease BstI has a subunit mol.wt. of 26,000 and is probably a loosely associated dimer. The enzyme shows maximum activity at pH values between 7 and 9.5, and in the presence of 0.5-2mM-Mg2+. NaCl inhibits the restriction enzyme activity. Restriction endonuclease BstI cleaves DNA in a position identical with that cleaved by endonuclease BamHI (for Bacillus amyloliquefaciens), i.e.: (formula: see text). In the presence of high concentrations of enzyme, DNA cleavage occurs at secondary sites. This side-specificity is enhanced by the addition of glycerol. Preliminary studies indicate that these sites are of the type: (formula: see text).


1982 ◽  
Vol 56 (2) ◽  
pp. 111-116 ◽  
Author(s):  
Masoodul Haque ◽  
Ather H. Siddiqi

ABSTRACTThe isoenzymes of acid and alkaline phosphatases and their histochemical localization were studied by polyacrylamide disc gel electrophoresis in four species of trematodes: Gigantocotyle explanatum from the liver and Gastrothylax crumenifer from the rumen of water buffalo (Bubalus bubalis) and Echinostoma malayanum and Fasciolopsis buski from the small intestine of the pig (Sus scrofa). Both acid and alkaline phosphatases were present in the tegument, gastrodermis, suckers, testes, ovary, eggs, vitellaria and uterus but alkaline phosphatase activity was demonstrated only in the parenchyma and excretory ducts. Polyacrylamide gel electrophoresis revealed two to four isoenzymes for both acid and alkaline phosphatase.


1973 ◽  
Vol 17 (2) ◽  
pp. 71-76
Author(s):  
Manabu Masuzawa ◽  
Takenobu Kamata ◽  
Yasuhiko Sakoyama ◽  
Yasuto Chiba ◽  
Zen-ichi Ogita

Sign in / Sign up

Export Citation Format

Share Document