SSC MTS EXAM

Detailed explanation-1: -Gram-positive bacteria lack an outer membrane but are surrounded by layers of peptidoglycan many times thicker than is found in the Gram-negatives. Threading through these layers of peptidoglycan are long anionic polymers, called teichoic acids.

Detailed explanation-2: -Most Gram-positive bacteria have a relatively thick (about 20 to 80 nm), continuous cell wall (often called the sacculus), which is composed largely of peptidoglycan (also known as mucopeptide or murein).

Detailed explanation-3: -The peptidoglycan (murein) sacculus is a unique and essential structural element in the cell wall of most bacteria. Made of glycan strands cross-linked by short peptides, the sacculus forms a closed, bag-shaped structure surrounding the cytoplasmic membrane.

Detailed explanation-4: -Gram-positive bacteria possess a thick multilayered peptidoglycan that is exposed to the cell exterior with covalently bound glycopolymers-teichoic acids-whereas Gram-negative bacteria have a thin, predominantly monolayered peptidoglycan covered by an additional lipid bilayer-the outer membrane or OM (16).