Extending the Carbon Chain: Hydrocarbon Formation Catalyzed by Vanadium/Molybdenum Nitrogenases

• Published in: Science (American Association for the Advancement of Science) Vol. 333; no. 6043; pp. 753 - 755
• Main Authors: Hu, Yilin, Lee, Chi Chung, Ribbe, Markus W.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 05.08.2011; The American Association for the Advancement of Science
• Subjects: Analytical, structural and metabolic biochemistry; Azotobacter vinelandii; Biocatalysis; Biological and medical sciences; Carbon; Carbon monoxide; Carbon Monoxide - metabolism; Catalysis; Catalysts; Chemical bonds; Chemical reactions; Deuterium; Electrons; Enzymes; Enzymes and enzyme inhibitors; Ethane; Ethylene; Ethylenes - metabolism; Fundamental and applied biological sciences. Psychology; General aspects, investigation methods; Hydrocarbons; Hydrocarbons - metabolism; Methane; Methane - metabolism; Molybdenum; Nitrogenase - chemistry; Nitrogenase - metabolism; Oxidation-Reduction; Product displays; Product distribution; Propylene; Substrate Specificity; Transition metals; Vanadium; Substrate; Carbon monoxide; Hydrocarbon; Organic compounds
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1206883

In a small-scale reaction, vanadium-dependent nitrogenase has previously been shown to catalyze reductive catenation of carbon monoxide (CO) to ethylene, ethane, propylene, and propane. Here, we report the identification of additional hydrocarbon products [α-butylene, n-butane, and methane (CH 4 )] in a scaled-up reaction featuring 20 milligrams of vanadium-iron protein, the catalytic component of vanadium nitrogenase. Additionally, we show that the more common molybdenum-dependent nitrogenase can generate the same hydrocarbons from CO, although CH 4 was not detected. The identification of CO as a substrate for both molybdenum- and vanadium-nitrogenases strengthens the hypothesis that CO reduction is an evolutionary relic of the function of the nitrogenase family. Moreover, the comparison between the CO-reducing capacities of the two nitrogenases suggests that the identity of heterometal at the active cofactor site affects the efficiency and product distribution of this reaction.