Side PanelExpand side panel Topic 6 Cultivation

Cell Metabolism

1. Catabolism

2. Anabolism

Catabolism

releases energy (think catalyze)

Anabolism

Consumed energy (

Cell matabolism visual

Nutritional Requirements

1. macronutrients

2. micronutrients

macronutrients

• required by ALL cells to build macromolecules

• C, N, P, S, O, H

micronutrients

• required by some cells
• includes Fe, Cu, Na, Mg, Mn, and others

Fundamentals of Nutrition

1. ENERGY SOURCE

2. ELECTRONS

3. CARBON SOURCE

1. ENERGY SOURCE

(for oxidation, providing electrons for ETC)

Photo (photosynthetic; organic or inorganic e-)

OR

Chemo (organic or inorganic)

2. ELECTRONS

organo

(e.g., H2, NH3, S0, NO2-)

litho

(e.g., glucose, acetate)

3. CARBON SOURCE

(for cell maintenance and division)

Fixed organic (C-C bonds)

heterotroph

Greek heterone = (an)other and trophe = nutrition

OR

Gaseous inorganic (CO2)

autotroph

Greek autos = self and trophe = nutrition

Funamentals of Nutrition Naming Visual

Appropiate Naming System for Metabolism Visual

Energy sources (3)

1. Chemoorganotrophs

2. Chemolithotrophs

3. Phototrophs

Chemoorganotrophs

energy from oxidation of organic compounds and electrons

Chemolithotrophs

• energy from oxidation of inorganiccompounds

• found only in prokaryotes

Phototrophs

• energy from light captured by pigments

• may be oxygenic or anoxygenic

Carbon Sources

Carbon is a major requirement for all organisms

1. heterotroph

2. autotroph

Carbon Source - heterotroph

• primary producers”

• fix C directly from CO2

Carbon Source - Heterotrophs

use organic molecules produced by autotrophs

Conservation Energy Visual - Carbon focused

Idea - energy stored within chemicals “saved up”

ATP - high energy bonds

Acquisition of Nitrogen

Microorganisms must be able to incorporate nitrogen into a usable form.

Assimilation of ammonia into glutamate/glutamine most common

Glutimate

Glutamite

Acquisition of Nitrogen - Critical to making numerous macromolecules

amino acids

nucleic acids

Nutrient Concentration

• growth rate depends on amount of nutrients available

• key nutrient available in the lowest amount will limit growth

Effects on Oxygen - condition

aerobic growth uses oxygen

anaerobic growth occurs without oxygen

Aerobic growth

• obligate aerobes require O2

• microaerophiles grow best in low levels of O2

anaerobic growth

• aerotolerant anaerobes aren’t harmed by O2 but don’t use it

• obligate anaerobes facultative cannot grow when O2 is present

• facultative anaerobes

facultative anaerobes

can grow in the absence of O2 but grow better when it is present

Toxic Oxygen Species

impact of O2 respiration on a cell depends on a cell’s available defenses

Toxic Oxygen Species - Singlet Oxygen

Toxic Oxygen Species - Superoxide anion

Toxic Oxygen Species - Hydroxyl radical and Hydrogen Peroxide

Catalase Test

Some microbles produce catalase

H2O2 + H2O2 → 2H2O + O2