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E I Pimenova

Publications and source records attributed to E I Pimenova.

6 recordsLinked to original sources
PubMed1989

[The characteristics of amino acid catabolism in bacteria of the genus Citrobacter].

The comparison of the occurrence of enzymes effecting the deamination of dicarbon, aromatic and oxyamino acids, as well as transamination enzymes, in Citrobacter bacteria and the activity levels of these enzymes was made. The constant sign of such bacteria was the presence of serine and threonine dehydratase activity. 92% of the strains showed the presence of phenylalanine deaminase. No tryptophan activity was established. 96-98% of Citrobacter strains possessed phenylalanine, tyrosine and tryptophan aminotransferases with alpha-ketoglutaric acid functioning as the acceptor of the amino group.

Amino Acids↗
PubMed1978

[Aromatic amino acid metabolism in Enterobacteriaceae microorganisms].

The authors revealed phenylalanine deaminase (PAD) in the majority of the Citrobacter strains investigated; the activity of PAD varied within a rather considerable range (0.3--4.58 micrometer of phenylpiruvate in 1 hr per 1 mg of bacterial protein). The presence of this enzyme thus served as an auxiliary biochemical test characterising this group of conditionally pathogenic microbes of the Enterobacteriacea family. Tyrosine decarboxylase was absent in 26 of 50 strains of Citrobacter examined. In the rest of the strains the activity of this enzyme was low. Consequently, tyrosine decarboxylase could not be used for identification of microorganisms of the Citrobacter genus.

Amino Acid Oxidoreductases↗
PubMedDate not supplied

[Catabolism of amino acids in bacteria of the genus Klebsiella].

Propagation and activity level of 18 enzymes catalyzing deamination reactions of dicarboxylic and oxyamino acids and enzymes of amino acid reamination and amino acid N-acyl-derivatives' deacylation have been studied in Klebsiella bacteria. Klebsiella the most actively utilizes serin, threonine, aspartic and glutamic acids and aromatic amino acids. The first three amino acids are utilized by deamination, aromatic acids- in aminotransferase reaction with alpha-ketoglutaric acid, glutamic acid--by deamination and decarboxylation. Besides, Klebsiella actively deacylates N-acyl-derivatives of amino acids.

Amino Acids↗
PubMedDate not supplied

[Isolation and various characteristics of tryptophan deaminase from Proteus vulgaris].

Tryptophan deaminase was isolated from Proteus vulgaris and purified. The procedure for enzyme purification included the cell destruction on USD-1, fractionation by ammonium sulphate, gel chromatography on ultragel AcA34, ion exchange chromatography on DEAE-cellulose. A degree of the enzyme purification--95, yield--5.7%. The pH optimum was 7.5, the temperature optimum--47 degrees C. The enzyme molecular weight (105 kD) was estimated by gel chromatography on Sephadex G-200, Km--5.0 mM in the K-phosphate buffer (pH 7.5). The SH groups are supposed to be present in the active site of the enzyme. The enzyme does not accelerate oxidation deamination of phenylalanine and tyrosine.

Amino Acid Oxidoreductases↗