Week #5 Intro to Microbial metabolism

Metabolism

The sum of controlled chemical reactions that occur within cells, including catabolism and anabolism.

Catabolism

The breakdown of nutrients that provides energy and precursor metabolites for anabolism and other cellular functions.

Anabolism

The biosynthesis process that uses energy and precursor metabolites from catabolism to create macromolecule subunits.

Redox Reactions

Reactions involving the transfer of electrons from an electron donor to an electron acceptor, crucial for energy extraction from nutrients.

Dehydrogenation Reactions

Biological oxidations that involve the transfer of hydrogen atoms (one electron plus one proton) during redox reactions.

Coenzymes

Electron carriers, such as NADH and FADH2, that are produced during catabolism and used to generate ATP.

ATP

The energy currency of the cell, synthesized through substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation.

Metabolic Pathways

Series of sequential chemical reactions organized in cells, with each step catalyzed by specific enzymes.

Active Site

The distinctive site on an enzyme where the substrate specifically fits and interacts to form an enzyme-substrate complex.

Cofactors

Non-protein chemical compounds (e.g., magnesium, iron) that assist enzymes in their catalytic activity.

Enzyme Inhibition

The process by which enzyme activity is reduced, which can be reversible (competitive/noncompetitive) or irreversible.

Glycolysis

The metabolic pathway that oxidizes glucose to produce pyruvate, NADH, and ATP, serving as a common pathway for cellular respiration and fermentation.

Krebs Cycle

A series of reactions that oxidize acetyl CoA to CO2, producing NADH, FADH2, and ATP.

Proton Motive Force

The potential energy generated by a proton gradient across a membrane, used to synthesize ATP and power other cellular processes.

Oxidase Test

A laboratory test that detects the presence of cytochrome c oxidase in the electron transport chain, distinguishing between bacterial species.

Theoretical ATP Yield

The maximum number of ATP molecules produced from the complete oxidation of one glucose molecule, estimated at 38 ATP.

Fermentation

A metabolic process that harvests energy from the oxidation of organic molecules without involving the Krebs cycle or electron transport chain.

Lactic Acid Fermentation

A type of fermentation carried out by lactic acid bacteria, producing lactic acid as a byproduct.

Anabolic Pathways

Metabolic pathways that synthesize new cellular components using ATP and precursor metabolites from catabolic pathways.

Amphibolic Pathways

Metabolic pathways, such as glycolysis and the Krebs cycle, that function in both anabolism and catabolism.