Korean J Dermatol.  1983 Feb;21(1):71-75.

Further Studies of Adenosine Deaminase in the Human Skin (II)

• Ihm CW
• Kim YP
• Choi YS

Abstract

Adenosine deaminase (adenosine aminohydrolase, E.C.3. 5. 4. 4; ADA), which catalyzes the deamination of adenosine to yield inosine and ammonia, was characterized in the human penile foreskin. ADA was found to be present in both layers of the skin with slightly higher activity in the epidermis(Epidermis; (7. 2+2. 3) * 10-4 unit/mg protein, Dermis;(5. 7 +1. 9) *10-4 unit/mg protein). The enzyme exhibited a broad pH optimum from 6. 5 to 8. 0 in both layers of the skin, and was heat-labile, being completely inactivated by heat treatment at 70C-75 C for 10 minutes. In contrast to the ADA of other tissue, the enzyme was inhibited by 2 mM of Cu2+, Fe2+ and Co2+ at pH7. 0 in both layers of the skin. The inhibitory effect of Cu2+ on the enzyme was stronger than other metal ions, and the enzyme was completely inactivated by 20 mM of Cu2+ in both layers. The Cu2+ inhibited enzyme activities which were recovered by adding EDTA. From the above results, it is suggested that the enzyme in both layers of the skin are consisted of same types of isozymes.

MeSH Terms

Adenosine Deaminase*
Adenosine*
Ammonia
Deamination
Edetic Acid
Foreskin
Hot Temperature
Humans*
Hydrogen-Ion Concentration
Inosine
Ions
Isoenzymes
Skin*
Adenosine
Adenosine Deaminase
Ammonia
Edetic Acid
Inosine
Ions
Isoenzymes