Identify the Archaebacterium.

The correct answer is Methanobacterium.

 Key Points

• Methanobacterium is a genus of microbes in the domain Archaea and is known as archaebacteria. They are methanogens, which means they produce methane as a metabolic byproduct.
• Archaebacteria are known for living in extreme environments, such as hot springs, salt lakes, or in the gut of ruminants where Methanobacterium can be found.
• They have unique properties that differentiate them from other bacteria, such as distinctive ribosomal RNA sequences and unique membrane lipids.

 Additional Information

• Acetobacter and Erwinia are types of true bacteria (eubacteria), not archaebacteria.
• Treponema is also a genus of bacteria, known for causing diseases like syphilis and yaws.