Amino acid composition of rat and human liver microsomes in normal and pathological conditions

1995 ◽  
Vol 15 (2) ◽  
pp. 111-116 ◽  
Author(s):  
Gheorghe Benga ◽  
William Ferdinand
Keyword(s):  
Liver Cirrhosis ◽  
Amino Acid ◽  
Obstructive Jaundice ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Human Subjects ◽  
Liver Microsomes ◽  
Normal Liver ◽  
Pathological Conditions ◽  
Species Specific

The amino acid composition of proteins from liver microsomes has been studied in rats and in human subjects with normal liver, with obstructive jaundice or liver cirrhosis. The pattern of the amino acid composition of microsomes appeared to be species-specific. Phenylalanine, threonine, serine, proline, histidine and [aspartic acid plus asparagine] were increased, while alanine, tyrosine, glycine and arginine were decreased in the human compared to the rat microsomes. In patients with obstructive jaundice of short duration (less than two months) only a slight decrease in leucine and phenylalanine could be noticed, while in the case of liver cirrhosis amino acid composition was markedly changed.

Amino acid composition of human liver mitochondrial membranes in normal and pathological conditions

1991 ◽  
Vol 11 (2) ◽  
pp. 95-100 ◽  
Author(s):  
Gheorghe Benga ◽  
Adriana Hodârnău ◽  
Rozalia Tilinca ◽  
Victoria Borza ◽  
William Ferdinand
Keyword(s):  
Liver Cirrhosis ◽  
Amino Acid ◽  
Obstructive Jaundice ◽  
Fatty Liver ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Normal Liver ◽  
Mitochondrial Membranes ◽  
Pathological Conditions ◽  
Methionine Content

The amino acid composition of proteins from liver mitochondrial membranes has been studied in patients with normal liver, with biliary diseases and fatty liver, with obstructive jaundice or liver cirrhosis. A characteristic pattern of the amino acid composition in patients with normal liver has been found. In the mitochondrial membranes of patients with fatty liver tryptophan and lysine were decreased while [aspartic acid plus asparagine] and [glutamic acid plus glutamine] were increased compared to their counterpart in the normal liver. In patients with obstructive jaundice of short duration (less than two months) only a slight decrease in methionine content was found, while in the case of liver cirrhosis amino acid composition was markedly changed.

scholarly journals Interrelation between plasma amino acid composition and growth hormone secretion in patients with liver cirrhosis.

1984 ◽  
Vol 31 (5) ◽  
pp. 557-564 ◽  
Author(s):  
SHOJIRO NAOMI ◽  
TERUHISA UMEDA ◽  
JUNICHI TAJIRI ◽  
JUNNOSUKE INOUE ◽  
SHINICHIRO HAMASAKI ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Liver Cirrhosis ◽  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Plasma Amino Acid

scholarly journals Site-directed mutation studies of human liver cytochrome P-450 isoenzymes in the CYP2C subfamily

1993 ◽  
Vol 289 (2) ◽  
pp. 533-538 ◽  
Author(s):  
M E Veronese ◽  
C J Doecke ◽  
P I Mackenzie ◽  
M E McManus ◽  
J O Miners ◽  
...  
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Human Liver ◽  
Liver Microsomes ◽  
Amino Acid Sequences ◽  
Site Directed Mutagenesis ◽  
Kinetics Of ◽  
Cytochrome P 450

Evidence from human studies in vivo and in vitro strongly suggests that the methylhydroxylation of tolbutamide and the 4-hydroxylation of phenytoin, the major pathways in the elimination of these two drugs, are catalysed by the same cytochrome P-450 isoenzyme(s). In the present study we used site-directed mutagenesis and cDNA expression in COS cells to characterize in detail the kinetics of tolbutamide and phenytoin hydroxylations by seven CYP2C proteins (2C8, 2C9 and variants, and 2C10) in order to define the effects of small changes in amino acid sequences and the likely proteins responsible in the metabolism of these two drugs in man. Tolbutamide was hydroxylated to varying extents by all expressed cytochrome P-450 isoenzymes, although activity was much lower for the expressed 2C8 protein. While the apparent Km values for the 2C9/10 isoenzymes (71.6-131.7 microM) were comparable with the range of apparent Km values previously observed in human liver microsomes, the apparent Km for 2C8 (650.5 microM) was appreciably higher. The 2C8 enzyme also showed quite different sulphaphenazole inhibition characteristics. The 4-hydroxylation of phenytoin was also more efficiently catalysed by the 2C9/10 enzymes. These enzymes showed similarities in kinetics of phenytoin hydroxylation and sulphaphenazole inhibition compared with human liver phenytoin hydroxylase. Also of interest was the observation that, among the 2C9 variants, small differences in amino acid composition could appreciably affect both tolbutamide and phenytoin hydroxylations. The amino acid substitution Cys-144->Arg increased both the rates of tolbutamide and phenytoin hydroxylations, while the Leu-359->Ile change had a greater effect on phenytoin hydroxylation. We conclude that: (1) although 2C8 and 2C9/10 proteins metabolize tolbutamide. only 2C9/10 proteins play a major role in human liver; (2) 2C9/10 proteins also appear to be chiefly responsible for phenytoin hydroxylation; and (3) subtle differences in the amino acid composition of these 2C9/10 proteins can affect the functional specificities towards both tolbutamide and phenytoin.

Effect of maternal diet on the amino acid composition of human uterine fluid

2014 ◽  
Author(s):  
Alexandra Jayne Kermack ◽  
Ying Cheong ◽  
Nick Brook ◽  
Nick Macklon ◽  
Franchesca D Houghton
Keyword(s):  
Amino Acid ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Maternal Diet ◽  
Uterine Fluid
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