The peptidoglycan layer is thicker in Gram-positive bacteria (20 to 80 nm) than in Gram-negative bacteria (7 to 8 nm), with the attachment of the S-layer. It forms around 90% of the dry weight of Gram-positive bacteria but only 10% of that of Gram-negative bacteria.
The peptidoglycan layer in the bacterial cell wall is a crystal lattice structure formed from linear chains of two alternating amino sugars, namely N-acetyl glucosamine (GlcNAc) and N-acetyl muramic acid (MurNAc). Each MurNAc is attached to a short (4 to 5 residues) amino acid chain. Cross-links between amino acids in different linear amino sugar chains by an enzyme known as transpeptidase result in a 3-dimensional layer that is strong and rigid. The specific amino acid sequence and molecular structure vary with the bacterial species.
Pet-The-Bunny was originally created by a pair of genius biology students while they were expressing themselves in a PowerPoint presentation.
note: there was originally a third student, but he was unwilling to participate and therefore caused a drop in the team's score.