Coenzyme B

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IntEnz
BRENDA
ExPASy
KEGG
MetaCyc

Coenzyme B is a critical cofactor in the biochemical processes of methanogenic archaea. It plays a vital role in the final step of methanogenesis, which is the biological production of methane.

Structure

Coenzyme B, also known as 7-mercaptoheptanoylthreonine phosphate, is characterized by its unique thiol group, which is essential for its function in enzyme catalysis. The presence of the thiol group allows Coenzyme B to participate in redox reactions that are crucial for methane production.

Function

In the process of methanogenesis, Coenzyme B acts as an electron donor. It interacts with coenzyme M to form a heterodisulfide, which is then reduced to regenerate the active forms of both coenzymes. This reaction is catalyzed by the enzyme methyl-coenzyme M reductase, which is the key enzyme in methane biosynthesis.

Biological Importance

Methanogenesis is an important anaerobic process carried out by methanogenic archaea, which are found in diverse environments such as wetlands, rumen of cattle, and anaerobic digesters. The production of methane by these organisms is a significant component of the global carbon cycle and has implications for climate change due to methane's role as a potent greenhouse gas.

Applications

Understanding the role of Coenzyme B in methanogenesis has applications in biotechnology and environmental science. For instance, manipulating methanogenic pathways can lead to improved biogas production and strategies to mitigate methane emissions from agricultural sources.

See also

• Methanogenesis
• Coenzyme M
• Methyl-coenzyme M reductase
• Archaea