| Developed and produced by www.MechanismsinMedicine.com Animation Description This animation starts with the explanation of bacterial cell wall synthesis, the process targeted by ß-Lactams. Structurally, most bacteria consist of a cell membrane surrounded by a cell wall and, for some bacteria, an additional outer layer. Internal to the cell membrane is the cytoplasm which contains ribosomes, a nuclear region and in some cases granules and/or vesicles. Depending on the bacterial species, a number of different external structures may be found such as a capsule, flagella and pili. In gram negative bacteria, the gap between the cell membrane and the cell wall is known as the periplasmic space. Most gram positive bacteria do not possess a periplasmic space but have only periplasm where metabolic digestion occurs and new cell peptidoglycan is attached. Peptidoglycan, the most important component of the cell wall, is a polymer made of N-acetyl muramic acid alternating with N-acetyl glucosamine which are cross-linked by chains of four amino acids. The function of the bacterial cell wall is to maintain the characteristic shape of the organism and to prevent the bacterium from bursting when fluid flows into the organism by osmosis. Synthesis of peptidoglycan and ultimately the bacterial cell wall occurs in a number of stages. One of the first stages is the addition of 5 amino acids to N-acetyl muramic acid. Next, N-acetyl glucosamine is added to the N-acetyl muramic acid to form a ... |
