What is teichoic acid?

What is teichoic acid?

• A. Polysaccharide linking peptidoglycan to the plasma membrane for rigidity and structure
• B. A lipid component of the cell membrane
• C. A protein component of the capsule
• D. A lipid A molecule in LPS

Answer: (A)

Teichoic acids are anionic polymers found in the thick cell wall of Gram-positive bacteria. They come in two forms: wall teichoic acids, which are covalently attached to peptidoglycan, and lipoteichoic acids, which are anchored in the cytoplasmic membrane by lipid groups. Their role is to contribute to the cell wall’s structure and rigidity, help regulate ion balance, and influence surface charge and interactions with the environment or host tissues. The description that emphasizes linking the peptidoglycan to the plasma membrane and supporting rigidity aligns best with what teichoic acids do, even though they are phosphate-containing polymers rather than true polysaccharides. The other options describe components that aren’t teichoic acids: a lipid component of the membrane would be a lipid, a protein component of the capsule would be a capsule protein, and lipid A is part of LPS in Gram-negative bacteria.

Teichoic acids are anionic polymers found in the thick cell wall of Gram-positive bacteria. They come in two forms: wall teichoic acids, which are covalently attached to peptidoglycan, and lipoteichoic acids, which are anchored in the cytoplasmic membrane by lipid groups. Their role is to contribute to the cell wall’s structure and rigidity, help regulate ion balance, and influence surface charge and interactions with the environment or host tissues. The description that emphasizes linking the peptidoglycan to the plasma membrane and supporting rigidity aligns best with what teichoic acids do, even though they are phosphate-containing polymers rather than true polysaccharides. The other options describe components that aren’t teichoic acids: a lipid component of the membrane would be a lipid, a protein component of the capsule would be a capsule protein, and lipid A is part of LPS in Gram-negative bacteria.