Bacterial Metabolism Flashcards
-synthesis of cellular constituents
Anabolism
- major pathway of glucose catabolism
Embden-Myerhof-Parnas Pathway(glycolysis)
-major pathway for glucose by obligate anaerobes
Entner-Duodoroff pathway
-major mechanism for ATP production, final pathway for complete oxidation of amino acids,fatty acids,and carbohydrates
Tricarboxylic acid cycle
-consist of polymeric backbones of repeating N acetylglucosamine and N acetyl muramic acid joined together by a tetrapeptide bonds
Peptidoglycan biosynthesis
cross linked peptidoglycan-murein sacculus
Cell wall peptidoglycan
envelope proteins-M proteins
Non peptidoglycan components
-dispensable,does not affect viability of the cell
Capsular polysaccharides
-strong rigid cell wall, devoid of protein and lipids, with teichoic acid
Gram positive
-more complex, thin peptidoglycan
Gram negative
Bacterial cell envelope
-contain unique LPS various proteins(transmembrane proteins) -porins,integral proteins bilayer
Outer membrane
Bacterial cell envelope
-asymmetrical, LPS
Enteric bacteria
Bacterial cell envelope
-all phospholipids
Non enteric
Bacterial cell envelope functions
barrier,
filter,
attachment site for phage and conjugation, proteases and other enzymes
-use inorganic compounds as sole source of carbon like CO2. Derive energy from light(photolithotrophs) or oxidation of inorganic(chemolithotrophs
Autotrophic(lithotrophs)
- use organic compounds as carbon source like glucose.Cant use CO2 as sole source of carbon.derive energy from li(photoorganotrophs), or inorganic-(chemoorganotrophs
Heterotrophic(organotrophic)
Nitrogen-major component of proteins and nucleic acids. Assimilated by
fixation,
reduction,
and ammonia assimilation
Oxygen is toxic for these anaerobes which lack 2 enzymes:
a. Superoxide dismutase-destroys SOD
b. Catalase-destroys hydrogen peroxide
-can resist exposure to oxygen, not killed
Aerotolerant anaerobes