Oxidative Decarboxylase UndA Utilizes a Dinuclear Iron Cofactor.

Area of Science:

• Biochemistry
• Enzymology
• Bioinorganic Chemistry

Background:

• Nonheme iron enzymes play crucial roles in biological catalysis.
• Decarboxylation reactions are essential metabolic processes.
• Dinuclear iron enzymes catalyze a variety of oxidative transformations.

Purpose of the Study:

• To characterize the structure and function of the UndA enzyme.
• To investigate the mechanism of dodecanoic acid decarboxylation.
• To determine if UndA represents a new class of dinuclear iron enzymes.

Main Methods:

• Optical spectroscopy
• Mössbauer spectroscopy
• Single turnover kinetic studies

Main Results:

• UndA contains a coupled dinuclear iron cluster.
• The enzyme catalyzes the decarboxylation of dodecanoic acid to undecene and CO2.
• The reaction stoichiometry indicates one product molecule formed per enzyme cluster per turnover.
• UndA is identified as the first diiron decarboxylase.

Conclusions:

• UndA expands the known catalytic activities of dinuclear iron enzymes.
• The coupled dinuclear iron cluster is essential for UndA's decarboxylase activity.
• This study provides new insights into the mechanisms of nonheme iron enzymes.