Question

Gram positive bacteria are more rigid than Gram negative bacteria because of the

• A. presence of multiple layers of peptidoglycan
• B. lack of D-amino acids in their cell wall
• C. presence of N-acetylgalactosamine in the peptidoglycan backbone
• D. presence of lipopolysaccharide

Answer 1

The correct option is A presence of multiple layers of peptidoglycan

Because gram-positive bacteria are surrounded by layers of peptidoglycan which is many times thicker than is found in the gram negatives. Gram-negative bacteria are surrounded by a thin peptidoglycan cell wall, which is surrounded by an outer membrane containing lipopolysaccharide which is not present in gram-positive bacteria.

So, the correct answer is 'presence of multiple layers of peptidoglycan'.