Cell wall- biogeterogenny-polymer - covers the entire surface of the cell - kc-the foundation of all bacteria - peptidoglycan component (murein). relatively more in Gram (+) bacteria-share mureinovoy network in about 40 layers is 30-70% by dry weight of the COP, Gram (-) only 1-2 layers (10% by dry weight kc) - provide rigidity and elasticity kc -protected from external influences -gives shape - through it-done-nutrient transport and excretion of metabolites in -positioned on its surface receptors (bacteriophage bacteriocins him.v-c) -supports a constant internal environment and can withstand pressure from within (30 atm) -sense dyes (define tinctorial properties)
removing the cellular structure leads to lysis of the bacteria, or the formation of protoplasts and spheroplasts of differing origin and osmotic stability protoplast of Gram (+) - Bacteria completely devoid kc, e.g. under the action of lysozyme, for the need to maintain a spherical shape in an isotonic medium (in hypo - and lose their integrity hypermedia) spheroplasts of Gram (-) - bacteria lacking kc part (spherical form even in an isotonic medium - are resistant to osmotic pressure difference m / s from the intra-and extracellular divisions) L - form (named after the Institute. D. Lister) - kc deprived bacteria, but are able to reproduce (spontaneous or induced). -There are stable (not capable of reversion) and unstable (return to original shape after removal of the causative factor). -Large and small balls (regardless of the original form cells (rods, cocci) L-forms of these bacteria morphologically indistinguishable) 3 The main shapes: - coccus - bacillus - spiral
Bacterial metabolism - combines two processes: Catabolism (dissimilation or energy metabolism) - cleavage of various substrates for energy and anabolism (assimilation or plastic metabolism) - synthesis of macromolecular compounds for the formation of cellular structures.
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