Question

Which of the following statements are TRUE for archaea?

• A. Cell wall in archaea contains muramic acid and D-amino acid
• B. N-Formylmethionine is the first amino acid to initiate new polypeptide chain synthesis in archaea
• C. Methionine is the first amino acid used during protein synthesis in archaea
• D. Membrane of archaea contains phytanyl rather than fatty acids

Hint:

Archaea have unique cell structures and metabolic processes, including the use of methionine in protein synthesis and phytanyl in their membranes.

Answer 1

The Correct Option is C, D

Step 1: Understanding the unique features of archaea.
Archaea are a group of microorganisms with unique features in their cell structure, metabolism, and protein synthesis mechanisms. They differ from bacteria and eukaryotes in several ways.

Step 2: Analyzing the options.
- (A) Incorrect, archaea do not contain muramic acid, which is specific to bacterial cell walls.
- (B) Incorrect, N-Formylmethionine is the first amino acid used in protein synthesis in bacteria, not in archaea.
- (C) Correct, methionine is indeed the first amino acid used during protein synthesis in archaea, similar to eukaryotes.
- (D) Correct, archaea have a unique membrane structure, where the lipid bilayer is composed of phytanyl groups (derived from isoprenoid units), not fatty acids as in bacteria and eukaryotes.
Step 3: Conclusion.
The correct statements about archaea are that methionine is the first amino acid in protein synthesis, and their membranes contain phytanyl rather than fatty acids.