AMP-deaminase from human preterm placenta – Kinetic regulatory properties of enzyme

Placenta ◽  
2011 ◽  
Vol 32 (9) ◽  
pp. 704-707 ◽  
Author(s):  
I. Rybakowska ◽  
A. Świeca ◽  
R. Milczarek ◽  
J. Klimek ◽  
K. Kaletha
Keyword(s):  
Amp Deaminase ◽  
Regulatory Properties

scholarly journals Developmental forms of human skeletal-muscle AMP deaminase. The kinetic and regulatory properties of the enzyme

1988 ◽  
Vol 249 (1) ◽  
pp. 255-261 ◽  
Author(s):  
K Kaletha ◽  
G Nowak
Keyword(s):  
Skeletal Muscle ◽  
Human Fetus ◽  
Human Skeletal Muscle ◽  
Fetal Tissue ◽  
Amp Deaminase ◽  
Half Saturation Constant ◽  
Substrate Saturation ◽  
Regulatory Ligands ◽  
Regulatory Properties ◽  
Similar Kinetic

AMP deaminase isoforms from human skeletal muscle can be separated chromatographically [Kaletha, Spychała & Nowak (1987) Experientia 43, 440-443]. In adult tissue nearly all the AMP deaminase activity was eluted from phosphocellulose with 0.75 M-KCl (‘adult’ isoform), and the remaining activity could be eluted with 2.0 M-KCl. Conversely, most of the AMP deaminase activity from 11-week-old fetal tissue was eluted from phosphocellulose with 2.0 M-KCl (‘fetal’ isoform). In the present paper the kinetic and regulatory properties of AMP deaminase extracted from 11- and 16-week-old fetal skeletal muscle are reported. The two isoforms from 11-week-old human fetus differed distinctly in these properties. The ‘fetal’ isoform had about 5-fold higher half-saturation constant (S0.5) value than the ‘adult’ form. It was also more sensitive to the influence of some important regulatory ligands (ADP, ATP and Pi), and exhibited a different pH/activity profile. The ‘adult’ isoform of AMP deaminase from fetal muscle and the enzyme from mature muscle possessed similar kinetic and regulatory properties. This isoform seems not to be subject to any major modifications during further ontogenesis. This is not true, however, for the ‘fetal’ isoform. In the muscle of 16-week-old human fetus, the ‘fetal’ isoform showed a peculiar, biphasic, type of substrate-saturation kinetics. This phenomenon may reflect appearance of the next, developmentally programmed, isoform of human skeletal-muscle AMP deaminase.

Regulatory properties of rat heart AMP deaminase

1979 ◽  
Vol 568 (1) ◽  
pp. 80-90 ◽  
Author(s):  
Krystian Kaletha ◽  
Andrzej Skladanowski
Keyword(s):  
Rat Heart ◽  
Amp Deaminase ◽  
Regulatory Properties

scholarly journals Regulatory Properties of AMP Deaminase from Snapper Muscle

1994 ◽  
Vol 60 (1) ◽  
pp. 103-106
Author(s):  
Takashi Matsumoto ◽  
Kumiko Terauchi ◽  
Nozomu Hirota
Keyword(s):  
Amp Deaminase ◽  
Regulatory Properties

scholarly journals Developmental changes of chicken liver AMP deaminase

1985 ◽  
Vol 231 (2) ◽  
pp. 329-333 ◽  
Author(s):  
J Spychała ◽  
K Kaletha ◽  
W Makarewicz
Keyword(s):  
Developmental Stages ◽  
Liver Extract ◽  
Kinetic Studies ◽  
Chicken Liver ◽  
Amp Deaminase ◽  
Enzyme Preparations ◽  
Enzyme Form ◽  
Substrate Saturation ◽  
Two Peaks ◽  
Regulatory Properties

The AMP deaminase activity measured in crude chicken liver extract did not change significantly during development. The livers of 10- and 14-day chick embryos, 1-day, 5-, 10- and 16-week-old chickens and adult hens were examined for the existence of multiple forms of AMP deaminase. Phosphocellulose column chromatography revealed the existence of two peaks of enzyme activity in the liver of 10- and 16-week-old chickens and adult hens. Kinetic studies with the preparations of AMP deaminase revealed sigmoid-shaped substrate-saturation curves at all developmental stages and hyperbolic-shaped saturation curves for the enzyme form appearing in 10-week-old chickens. All AMP deaminases investigated were susceptible to activation by ATP and inhibition by Pi. Kinetic and regulatory properties as well as pH optima of all the enzyme preparations tested indicate that AMP deaminase isolated from the embryos and from 1-day-old chicks was similar to the form I isolated from adult hens and differed significantly from the form II of this enzyme.

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