Premium
The Quantitative Significance of the Two Transsulfuration Enzymes for Tissue H2S Production
Author(s) -
Xie Peter,
Kabil Omer,
Vitvitsky Victor,
Banerjee Ruma
Publication year - 2011
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.25.1_supplement.912.3
Subject(s) - cystathionine beta synthase , transsulfuration , cystathionine gamma lyase , kidney , enzyme , chemistry , cysteine , western blot , homocysteine , biochemistry , biology , endocrinology , gene
Hydrogen sulfide (H 2 S) is a gaseous signaling molecule that participates in various physiological processes such as regulation of blood pressure. Cystathionine beta‐synthase (CBS) and gamma‐cystathioninase (CSE) are the two enzymes that are responsible for the formation of H 2 S in the transsulfuration pathway. Quantitative Western blot analysis was used to determine the relative abundance of each enzyme in murine liver and kidney. In this study, we report quantification of CBS and CSE in murine liver and kidney and their contribution to H 2 S generation in these tissues and in brain. Our results show that the level of CBS protein is significantly lower than CSE; 60‐fold and 20‐fold in liver and kidney respectively. Levels of both enzymes are higher in liver compared to kidney, 2‐fold and 6‐fold for CBS and CSE respectively. At high substrate concentrations (20 mM each cysteine and homocysteine), CBS and CSE contribute equally to H 2 S production in liver extract while CBS constitutes the major source of H 2 S in kidney and brain with CSE contributing approximately 20% and 6% respectively. Determination of tissue levels of these enzymes is important for therapeutic reasons that aim to specifically modulate H 2 S synthesis in tissue‐specific manner.