Polymorphism of red cell phosphoglucomutase, adenylate kinase and adenosine deaminase in a Polish population.

Genetic variants of PGM1, AK and ADA were studied in a sample of unrelated individuals from the Polish population. The gene frequencies observed are: PGM1/1: 0.715, AK1: 0.962 AND ADA1: 0.940.     

ECTO-enzyme activity of human erythrocyte adenosine deaminase

Summary Adenosine deaminase is found primarily in the cytoplasm of many cell types. In the human erythrocyte, about 30 per cent of the total adenosine deaminase activity is membrane associated, and about two-thirds of this is inactivated by treatment of intact erythrocytes with the nonpenetrating reagent diazotized sulfanilic acid, without affecting lactate dehydrogenase, a soluble cytoplasmic enzyme. This indicates that within the cell membranes, the catalytic site of about two-thirds of the adenosine deaminase faces the external medium, i.e., ecto adenosine deaminase. Localization of adenosine deaminase activity at the cell membrane is demonstrated directly by electron microscopy by use of the substrate 6-Chloropurine ribonucleoside, which is dechlorinated by adenosine deaminase to produce Cl^–, which is precipitated at its locus of formation by added Ag⁺, and the precipitated AgCl converted into the electron dense Ag⁰ upon exposure to light.From the Hydropathic Profile of the amino acid sequence of adenosine deaminase it is evident that there are two hydrophobic domains of sufficient length to span a biological membrane, and it is proposed that these domains could function to anchor the enzyme to the membrane.The importance of adenosine deaminase is indicated by the fatal immuno-deficiency which results from untreated genetic adenosine deaminase deficiency. It may be important to determine whether the amount of ecto adenosine deaminase activity is better suited to assess the clinical status of adenosine deaminase deficient patients that the currently used total cellular enzyme activity.Abbreviations ADA Adenosine Deaminase - LDH Lactate Dehydrogenase - HEPES N-2-Hydroxyethylpiperazine-N-2-ethanesulfonic acid - CPR 6-Chloropurine Ribonucleoside - SDS Sodium Dodecyl Sulfate - NAD -Nicotinamide Adenine Dinucleotide - HBSS Hank's Balanced Salt Solution - DASA Diazotized Sulfanilic Acid     

Increased erythrocyte adenosine deaminase activity without haemolytic anaemia

A 4-fold increase of red blood cell adenosine deaminase (ADA) activity was found in a patient without haemolytic anaemia, but with mild anisopoikilocytosis. High-performance liquid chromatography showed a 40% reduction of adenosine-5'-triphosphate (ATP) while all the other nucleotides were in normal ranges. The patient's parents (first cousins) and a brother displayed the same enzyme activities as the controls. This observation suggests that mild increases of ADA activity is neither a marker for congenital hypoplastic anaemia as previously reported nor associated with haemolytic anaemia.     

Adenosine deaminase,adenylate kinase and acid phosphatase polymorphism in a French-Canadian population

Summary Adenosine deaminase (ADA), adenylate kinase (AK1), and acid phosphatase (ACP1) red blood cell enzymes were studied for allelic variation in a French-Canadian population from Quebec City, Canada. Allele frequencies in 887 unrelated individuals were for ACP1, ACP1^*A: 0.305; ACP1^*B: 0.635 and ACP1^*C: 0.060, for ADA, ADA^*1: 0.969, ADA^*2: 0.031, and for AK1, AK1^*1: 0.976, AK1^*2: 0.024. The allele frequencies for each enzyme were identical to those previously reported in other Caucasian populations.     

Activity of adenosine deaminase and adenylate deaminase on adenosine and 2', 3(')-isopropylidene adenosine: role of the protecting group at different pH values

The deamination rate of 2',3'-isopropylidene adenosine catalyzed by adenosine deaminase (ADA) from calf intestine and adenylate deaminase (AMPDA) from Aspergillus species has been evaluated and compared with that of the enzymatic reactions of adenosine, to elucidate the influence of the protecting group on enzyme activity.     

Polymorphism of adenosine deaminase in the pig: allelic variation in erythrocytes

Within the frame of our investigations on genetic variation of pig red cell enzymes, by means of enzymo-electrophoresis and spectrophotometric measurements, four kinds of adenosine deaminase phenotypic patterns were identified in haemolysates from 542 Belgian Landrace and 502 Pietrain pigs. Segregation data are consistent with the hypothesis that these phenotypes are determined by two codominant alleles ADA ^A and ADA ^B and a recessive silent allele ADA ^O, at an autosomal locus. Differences in gene frequencies between the two breeds are highly significant.