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The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
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The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis

Published on: March 17, 2010

The development of cystathionase activity during the first year of life

S H Zlotkin, G H Anderson

    Pediatric Research
    |January 1, 1982
    PubMed

    Insights

    Hepatic cystathionase activity in infants develops with age, with full-term infants showing higher levels than pre-term infants. Premature infants can produce cysteine if given methionine, despite lower initial enzyme activity.

    Area of Science:

    • Biochemistry
    • Pediatric Physiology
    • Enzymology

    Background:

    • Hepatic cystathionase (EC 4.4.1.1) is crucial for amino acid metabolism.
    • Understanding its developmental trajectory in infants is vital for nutritional support.

    Purpose of the Study:

    • To investigate the developmental patterns of hepatic cystathionase activity in relation to gestational and postnatal age.
    • To assess cystathionase distribution in other infant organs.
    • To evaluate the potential for endogenous cysteine production in premature infants.

    Main Methods:

    • In vitro enzymatic assays were performed on liver, kidney, adrenal, and pancreas tissues from infants.
    • Enzyme activity was measured and correlated with infant age (gestational and postnatal).

    Main Results:

    • Hepatic cystathionase activity is significantly influenced by both gestational and postnatal age.
    • Full-term infants exhibit higher baseline activity than premature infants, with rapid postnatal increases.
    • Significant cystathionase activity is found in kidneys and adrenals, but not the pancreas, in both infant groups.

    Conclusions:

    • Infant cystathionase activity matures postnatally, with variations based on prematurity.
    • Premature infants possess the enzymatic capacity for endogenous cysteine synthesis, contingent upon methionine availability.

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