《微生物学》课程教学课件（PPT讲稿）The procaryotic cell wall

The procaryotic cell wall

The procaryotic cell wall

Oxidative phosphorylation occurs at cell membrane since there are no mitochondria) HAw AWIOSAWI Cytoplasm Cell membrane The cell wall is outside of cell membrane rigid, protecting cell from osmotic lysis

Cytoplasm Oxidative phosphorylation occurs at cell membrane (since there are no mitochondria). Cell membrane The cell wall is outside of cell membrane – rigid, protecting cell from osmotic lysis. Cell Wall

The Cell Envelope Gram stain Gram Positive Gram Negative

The Cell Envelope Gram Positive Gram Negative

Gram Positive Gram Negative Fixation Crystal violet lodine treatment Decolorization Counter stain safranin

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Cell membrane cell wall ( plus outer membrane Cell wal peptidoglycan attached structures

Cell Envelope • Cell membrane + cell wall (+ plus outer membrane) • Cell wall – peptidoglycan – attached structures

Gram positive Peptidoglycan Plasma membrane Gram negative Outer membrane Peptidoglycan Periplasmic space Plasma membrane

Gram positive Gram negative

GRAM POSITIVE CELA ENVELOPE Degradative enzyme Lipoteichoic acid Peptidoglycan-tejchoic acid 倡但含飞 Cytoplasmic membrane Cytoplasm

Cytoplasm Lipoteichoic acid Peptidoglycan-teichoic acid Cytoplasmic membrane GRAM POSITIVE CELL ENVELOPE Degradative enzyme

Peptidoglycan single macromolecule highly cross-linked surrounds cell provides rigidity

Peptidoglycan • single macromolecule • highly cross-linked • surrounds cell • provides rigidity