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Bacteria are protected by a rigid cell wall composed of peptidoglycans. LEARNING OBJECTIVE [ edit ] Memorize the characteristics of a bacterial cell wall KEY POINTS [ edit ] A cell wall is a layer located outside the cell membrane found in plants, fungi, bacteria, algae, and archaea. A peptidoglycan cell wall composed of disaccharides and amino acids gives bacteria structural support. The bacterial cell wall is often a target for antibiotic treatment. TERM [ edit ] binary fission The process whereby a cell divides asexually to produce two daughter cells. Give us feedback on this content: FULL TEXT [ edit ] Bacterial cells lack amembranebound nucleus. Theirgeneticmaterial is naked within thecytoplasm. Ribosomes are their only type of organelle. The term "nucleoid" refers to the region of the cytoplasm where chromosomal DNA is located, usually a singular, circularchromosome. Bacteria are usually singlecelled, except when they exist in colonies. These ancestral cells Register for FREE to stop seeing ads reproduce by means of binary fission, duplicating their genetic material and then essentially splitting to form two daughter cells identical to the parent. A wall located outside the cell membrane provides the cell support, and protection against mechanical stress or damage from osmotic rupture and lysis . The major component of the bacterial cell wall ispeptidoglycan or murein. This rigid structure of peptidoglycan, specific only to prokaryotes, gives the cell shape and surrounds the cytoplasmic membrane. Peptidoglycan is a huge polymer of disaccharides (glycan) cross linked by short chains of identical amino acids(peptides) monomers. The backbone of the peptidoglycanmolecule is composed of two derivatives of glucose: Nacetylglucosamine (NAG) and Nacetlymuramic acid (NAM) with a pentapeptide coming off NAM and varying slightly among bacteria. The NAG and NAM strands are synthesized in the cytosol of the bacteria. They are connected by interpeptide bridges. They are transported across the cytoplasmic membrane by a carrier molecule called bactoprenol. From the peptidoglycan inwards all bacterial cells are very similar. Going further out, the bacterial world divides into two major classes: Gram positive (Gram +) and Gram negative (Gram ). The cell wall provides important ligands for adherence andreceptor sites for viruses or antibiotics. Bacterial Cell Wall The anatomy of bacterial cell structure.