Cell Wall of Acid Fast Contains an inner peptidoglycan layer and an outer membrane The inner peptidoglycan layer is joined to the cell membrane by the Phosphatidyinositol mannosides (PIM) Also the inner peptidoglycan layer is joined to an arabinogalactan layer (arabinose and galactose) by a lipoarabinomannan The arabinogalactan layer is attached directly to the mycolic acids layer.

@ The mycolic acids layer is followed by a layer of acyl Porins are found to transport the hydrophilic molecules through the outer membrane Proteins are located on the surface of Mycolic acids are esterified to form polysaccharides (wax D) and Lipids are responsible for : * Acid fast staining * Stickiness of mycobacteria

Bacterial Loss of cell wall because murein for wall synthesis is Spheroplasts: gram negative Protoplasts: gram positive Origin: * Spontaneous (Streptobacillus, Bacteroides) * Presence of penicillin or lysozyme * Destruction of wall by complement * Absence of nutrient for wall No pathological or clinical significance.

Bacterial Cell Membrane Composed of 3 2 phospholipids layers with phosphate heads and lipid They are hydrophilic at their phosphate heads and hydrophobic at their lipid The hydrophobic lipid tails point inwards and the hydrophilic phosphate heads point Glycoproteins point outwards & attached to carbohydrate chain

@ Integral proteins help to anchor the cytoskeleton in Transmembrane proteins have enzymatic activity & catalyze chemical The third layer is the hydrophobic It contains proteins (70%) and lipids ٍ CM: semipermeable to nutrients, water, Folded towards cytoplasm to form mesosome

Functions of Cell Forms an osmotic barrier between cytoplasm and Transport of: # Respiratory electrons # Nutrients inside cell. # Waste product outside Synthesis and transfer of peptidoglycan, teichoic acids, & other contents of cell Secretion of extracellular enzymes and Segregation of chromosomal and plasmid DNA into daughter cells.

Mainly invaginations of cell Functions include: # Involved in nuclear division # Provide respiratory enzymes # Excretion of material outside the cell # Involved in cell wall synthesis # Involved in cell wall Convoluted & formed of lamellae or Developed in mycobacteria, E. coli, May join cell wall or nuclear body

Contains: water, ions, metabolites, proteins, nucleic acids, storage granules, Ribosomes actively translating messenger RNAmessenger RNA into Storage granules serve as reserves of energy and Metachromatic (volutin) granules are reserves of high energy phosphates in Contains the bacterial chromosome as a single circular molecule.

Bacterial Bacterial chromosomal DNA is not enclosed by an The chromosomal DNA molecule is 1.6 mm in a form of Plasmid is a separate DNA molecule that can replicate Plasmids are double-stranded and circular. Their number can range from 1 to Plasmids can integrate and replicate with bacterial cells.

Induced by: Changes of pH, temp., oxygen tension, nutrients, waste products, moisture, minerals (Ca ++, Mn, Differences from vegetative cells: # More resistant to heat, disinfectants, dryness, starvation # Low water content (5 - 20%) # Thick, impermeable coat # Low metabolic activity # Contain Ca ++ and dipicolinic acid

Endospore Endospores form within a vegetative bacterial Exosporium: a thin delicate Spore coat: thick layer of protein & Cortex: made of Core Core: contains ribosomes and nucleoid

Cycle of spore formation and Bacterium makes a copy of its chromosome DNA & the bacterial cell membrane begins invaginating inward until there’s a little daughter cell within the mother Next, membrane of mother cell surrounds the daughter cell. Then two membrane layers will surround the daughter Then a thick peptidoglycan wall forms and a tough outer protein coat forms around all daughter cell, which is now spore.