Schematic diagram of bacterial cell walls G ram+ Gram- eptidoclycan Peptidoglycan -Membrane ,Membrane Periplasm Lipopolysaccharide and protein Bacteria can be divided into two major groups. called gram-positive and gram-negative. The original distinction between gram-positive and gram-negative was based on a special staining procedure, the Gram stainGram+ Gram￾Schematic diagram of bacterial cell walls Bacteria can be divided into two major groups, called gram-positive and gram-negative. The original distinction between gram-positive and gram-negative was based on a special staining procedure, the Gram stain