Micro Ch 10 (Metabolism)

(metabolism)

Metabolism

Sum of all the chemical reactions in a cell, includes:  catabolism and anabolism

Anabolism

•Buildup of small molecules

•Products are large molecules

•Photosynthesis

•Mediated by enzymes

•Energy is required (endergonic)

Catabolism

•Breakdown of large molecules

•Products are small molecules

•Glycolysis, Kreb’s cycle

•Mediated by enzymes

•Energy released (exergonic)

Dehydration Reaction

glycosidic bond between two glucose molecules to generate maltose requires the removal of water molecule and energy from ATP

Hydrolysis

breaking peptide bond between two amino acids requires a water molecule that adds an H and OH to amino acids

Apoenzyme

protein component of an enzyme

Cofactors

non-protein

Holoenzyme

aponenzyme + cofactor

noncompetitive inhibition

the regulator molecule does not bind in the same site as the substrate

Ribozymes

 are RNA molecules that catalyze reactions on other RNA.

 constitutive enzyme

 always present and in relatively constant amounts, regardless of the cellular environment.

enzyme induction

enzymes appear (are induced) only when suitable substrates are present

endergonic:-require the addition of energy

ATP

a three-part molecule consisting of a nitrogen base (adenine) linked to a 5-carbon sugar (ribose), with a chain of three phosphate groups bonded to the ribose.

Photophosphorylation

 the ATP is formed through a series of sunlight-driven reactions.

What is glucose broken by?

glycolysis

Denaturation

loss of a protein

Phosphorylation

Creatine Phosphate + ADP à creatine + ATP

Oxidative Phsophorylation

1. electron transport chain

2. Chemiosmosis

Anaerobic Respiration

no oxygen required

Denitrification- reduce nitrite to nitric oxide, nitrous oxide, and nitrogen gas

Aerobic respiration

 -converts glucose to CO2 and allows the cell to recover significant amounts of energy

Fermentation

incomplete oxidation of glucose or other carbohydrates in the absence of oxygen. 

Alcoholic fermentation

 in yeast or bacterial species that have metabolic pathways for converting pyruvic acid to ethanol. decarboxylation of pyruvic acid to acetaldehyde, followed by a reduction of the acetaldehyde to ethanol. In oxidizing the NADH formed during glycolysis, NAD is regenerated, which allows the glycolytic pathway to continue.

Lactic acid fermentation

Mycobacterium

Obligate aerobes require oxygen for metabolism

Staphylococcus, E. coli

Facultative anaerobes can use oxygen, but also have anaerobic methods of energy production

Beta oxidation

2-carbon units are successively transferred to coenzyme A, creating acetyl CoA, which enters the Krebs cycle.

amphibolism

 to integrate catabolic and anabolic pathways to improve cell efficiency

 loss of electrons from the photocenter has two major effects

It creates a vacancy in the chlorophyll molecule forceful enough to split an H2O molecule into hydrogen (H+) (electrons and hydrogen ions) and oxygen (O2)

Photophosphorylation

located in this same thylakoid uses the energy from H+ transport to phosphorylate ADP to ATP.

Amphibolic metabolism

can integrate catabolic and anabolic pathways to improve cell efficiency