scholarly journals Amino-acid composition of pyruvate kinase M2 isoenzyme variants from rat liver and Morris hepatoma 7777.

1998 ◽  
Vol 45 (3) ◽  
pp. 775-780 ◽  
Author(s):  
J Ignacak ◽  
M Gumińska ◽  
J Steczko
Keyword(s):  
Amino Acid ◽  
Pyruvate Kinase ◽  
Rat Liver ◽  
Acid Content ◽  
Polyacrylamide Gel Electrophoresis ◽  
Amino Acid Content ◽  
Normal Rat ◽  
Morris Hepatoma ◽  
Amino Acid Analyser ◽  
Blue Sepharose

Cytosolic fractions B (salted out between 51-70% ammonium sulphate saturation) from rat liver and Morris hepatoma 7777, containing pyruvate kinase (EC 2.7.1.40) M2 isoenzymes, were purified by affinity chromatography on Blue Sepharose CL-6B. When compared by polyacrylamide gel electrophoresis at pH 8.3, all three M2 pyruvate kinase variants from Morris hepatoma 7777 had lower mobilities (alpha2, beta2, gamma3) than the three corresponding variants (alpha1, beta1, gamma2) from normal rat liver. Using an automatic amino-acid analyser, significant differences in selected amino-acid content have been found in corresponding highly purified gamma3 and gamma2 variants from Morris hepatoma and normal rat liver, respectively. The gamma3-variant of the Morris hepatoma M2 isoenzyme had twice the amount of L-tyrosine and L-cysteine, and a content of L-serine higher by 20% than the corresponding gamma2 variant of the normal rat liver M2 isoenzyme. It contained, however, significantly less dicarboxylic amino acids which explains its lower electrophoretic mobility. It showed also a decrease (by about 10%) in several other amino-acid content, corresponding to a 10% decrease in the tumour enzyme molecular mass.

scholarly journals N-acetylneuraminic acid, phosphate and thiol groups of pyruvate kinase isoenzymes from Morris hepatoma 7777 and normal rat liver.

1997 ◽  
Vol 44 (2) ◽  
pp. 201-208 ◽  
Author(s):  
J Ignacak ◽  
M Gumińska
Keyword(s):  
Pyruvate Kinase ◽  
Electrophoretic Mobility ◽  
Rat Liver ◽  
Amino Acid Content ◽  
Normal Liver ◽  
Regulatory Change ◽  
Thiol Groups ◽  
Acetylneuraminic Acid ◽  
Normal Rat ◽  
Morris Hepatoma

The highest amount of N-acetylneuraminic acid (AcNeu) was found in pyruvate kinase isoenzyme L from normal rat liver (24 moles/mole of enzyme tetramer), with the highest electrophoretic mobility. On the other hand, isoenzyme M2 from Morris hepatoma 7777, with the lowest electrophoretic mobility, had the lowest AcNeu content (5 moles/mole of enzyme tetramer). This tumour isoenzyme M2 of pyruvate kinase was, however, characterised by the highest phosphate content (12 moles/mole protein), in comparison to isoenzyme L (3 moles/mole protein) or normal liver isoenzyme M2 (6 moles/mole protein). This could indicate a regulatory change caused by reversible enzyme phosphorylation and dephosphorylation or sialization and desialization. Despite these differences, the sum of the two negatively charged residues was lower in tumour pyruvate kinase isoenzyme M2, with the slowest migration rate, than in normal rat liver isoenzyme M2. Moreover, isoenzyme M2 from tumour material, in comparison with isoenzyme M2 from normal rat liver, had a twice as high content of thiol groups (20 moles/mole protein), especially of free and superficially located ones, than the isoenzyme M2 from normal liver (10 moles/mole protein). This may explain abnormal susceptibility of tumour isoenzyme M2 to stereospecific inhibition by exogenous L-cysteine, and indicate genetically dependent changes in amino-acid content of tumour enzyme which take place during cell tumourigenic transformation.

scholarly journals Comparison of pyruvate kinase variants from rat liver and Morris hepatoma 7777, obtained by an affinity chromatography on blue sepharose CL-6B.

1993 ◽  
Vol 40 (2) ◽  
pp. 261-267 ◽  
Author(s):  
J Ignacak ◽  
M Gumińska
Keyword(s):  
Affinity Chromatography ◽  
Pyruvate Kinase ◽  
Rat Liver ◽  
Kinase Activity ◽  
Signal Molecules ◽  
Pyruvate Kinase Activity ◽  
Normal Rat ◽  
Morris Hepatoma ◽  
Blue Sepharose ◽  
Main Substrate

Fractions A (salted out by ammonium sulphate between 21-30% saturation), and fractions B (salted out between 51-70% saturation) of pyruvate kinase (EC 2.7.1.40.) corresponding respectively to pyruvate kinase types L and M2 from rat liver and Morris hepatoma 7777 were purified by an affinity chromatography on Blue Sepharose CL-6B. Peaks of inactive proteins were eliminated and the enzyme fractions bound biospecifically to the gels were eluted by free ADP. The molecular mass of purified hepatoma pyruvate kinase fraction B was smaller than that of liver pyruvate kinase fraction B. Morris hepatoma pyruvate kinase fraction B represented a variant of type M2, characterised by greatest affinity to 2-phosphoenolpyruvate as a main substrate and different sensitivity to low-molecular effectors in comparison with types L from both liver and hepatoma and in comparison with type M2 from normal rat liver. Only this hepatoma fraction B showed a tumour specific sensitivity to L-cysteine and was insensitive to normal signal molecules i.e. to ATP and fructose-1,6-diphosphate which influence liver pyruvate kinase activity. L-Cysteine inhibited the tumour fraction B of pyruvate kinase by decreasing its Vmax and increasing the Km values in relation to 2-phosphoenolpyruvate.

scholarly journals The effects of insulin and adrenaline on the amino-acid content of blood

1933 ◽  
Vol 27 (5) ◽  
pp. 1648-1654 ◽  
Author(s):  
James Murray Luck ◽  
Stanley Wallace Morse
Keyword(s):  
Amino Acid ◽  
Acid Content ◽  
Amino Acid Content

Evaluation of seed amino acid content and its correlation network analysis in wild soybean (Glycine soja) germplasm in Japan

2021 ◽  
Vol 19 (1) ◽  
pp. 35-43
Author(s):  
Awatsaya Chotekajorn ◽  
Takuyu Hashiguchi ◽  
Masatsugu Hashiguchi ◽  
Hidenori Tanaka ◽  
Ryo Akashi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Acid Content ◽  
Free Amino ◽  
Glycine Soja ◽  
Wild Soybean ◽  
Amino Acid Content ◽  
Soybean Seeds ◽  
Free Amino Acid Content

AbstractWild soybean (Glycine soja) is a valuable genetic resource for soybean improvement. Seed composition profiles provide beneficial information for the effective conservation and utilization of wild soybeans. Therefore, this study aimed to assess the variation in free amino acid abundance in the seeds of wild soybean germplasm collected in Japan. The free amino acid content in the seeds from 316 accessions of wild soybean ranged from 0.965 to 5.987 mg/g seed dry weight (DW), representing a 6.2-fold difference. Three amino acids had the highest coefficient of variation (CV): asparagine (1.15), histidine (0.95) and glutamine (0.94). Arginine (0.775 mg/g DW) was the predominant amino acid in wild soybean seeds, whereas the least abundant seed amino acid was glutamine (0.008 mg/g DW). A correlation network revealed significant positive relationships among most amino acids. Wild soybean seeds from different regions of origin had significantly different levels of several amino acids. In addition, a significant correlation between latitude and longitude of the collection sites and the total free amino acid content of seeds was observed. Our study reports diverse phenotypic data on the free amino acid content in seeds of wild soybean resources collected from throughout Japan. This information will be useful in conservation programmes for Japanese wild soybean and for the selection of accessions with favourable characteristics in future legume crop improvement efforts.

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