microbial metabolism & growth
DESCRIPTION
Microbial Metabolism & Growth. Basic Organic Chem Review. Four Basic Types of Macromolecules A) Proteins (Made up of Amino Acids) B) Nucleic Acids (Made up of Nucleotides) C) Carbohydrates (Mainly Carbon, Hydrogen, and Oxygen in a 1:2:1 ratio) D) Lipids (Mainly Carbon & Hydrogen). - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/1.jpg)
Microbial Metabolism & Growth
![Page 2: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/2.jpg)
Basic Organic Chem Review
• Four Basic Types of Macromolecules• A) Proteins (Made up of Amino Acids)• B) Nucleic Acids (Made up of Nucleotides)• C) Carbohydrates (Mainly Carbon, Hydrogen,
and Oxygen in a 1:2:1 ratio)• D) Lipids (Mainly Carbon & Hydrogen)
![Page 3: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/3.jpg)
A. Proteins
• consist of long, complex chains of amino acids (20 kinds)
• the most abundant organic components of microbes
• function as structural materials as well as __________
• destruction of the proteins in an organism usually results in death
![Page 4: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/4.jpg)
Protein structure: amino acids
• AMINO ACIDS are the building blocks of proteins
a specific amino acid
![Page 5: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/5.jpg)
Protein structure: amino acids
NOTE: All amino acids look alike except for the highlightedportions. This is important in building many different proteins.
![Page 6: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/6.jpg)
Peptide bonding of amino acids
• Proteins are built by linking amino acids end to end. Each link is a ____________.
![Page 7: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/7.jpg)
Protein structure: Primary
![Page 8: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/8.jpg)
Protein structure: Secondary
![Page 9: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/9.jpg)
Protein structure: 3 dimensional • The 3 dimensional shape of a protein
dictates its function.• If the 3 dimensional shape is altered, the
protein is destroyed.
![Page 10: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/10.jpg)
![Page 11: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/11.jpg)
Protein structure: Quaternary (Hemoglobin)
![Page 12: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/12.jpg)
Protein _________
Altered 3-D shape = destroyed protein
![Page 13: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/13.jpg)
B. Nucleic Acids• Two types function in all living
things: • _____ ( deoxyribonucleic acid )
acts as the genetic material of the chromosome
• _____ ( ribonucleic acid ) functions
in the construction of proteins• Both DNA and RNA are composed
of repeating units called nucleotides
• As with proteins, the nucleic acids cannot be altered without disrupting the organism or killing it.
![Page 14: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/14.jpg)
C. Carbohydrates
• 1. general formula = (CH2O)n
• 2. sugars, starches, cellulose, etc• 3. have a vital function as energy sources
in cells• 4. also found in several cellular structures
such as cell walls and bacterial capsules • 5. monosaccharides are the simplest
carbohydrates, the building blockse.g. ________, fructose C6H12O6
![Page 15: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/15.jpg)
Carbohydrates• 6. disaccharides are double sugars (2
monosaccharides bonded together)– e.g. _______ (table sugar) is one glucose and
one fructose– C12H22O11: one H2O lost when bond forms
glucose fructose
NOTE: 2 monosaccharides linked together.
Dehydration Synthesis (Putting together) Hydrolysis (breaking apart)
![Page 16: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/16.jpg)
OCH2OH CH2OH CH2OH CH2OH
H HH H
HH
H
H
H
H
H
H
HH
HH
H
HHO O O
OH
OHOH
OH OH OH
OH OH OHHO HO HO OHO H2O
OH
Dehydration SynthesisHydrolysis
Macromolecules (How to Make Them)
![Page 17: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/17.jpg)
C. Carbohydrates
• 7. complex sugars are called polysaccharides or complex carbohydrates (e.g. starch, cellulose )
• long chains of sugars:
sugar—sugar—sugar—sugar—sugar—sugar—sugar—
![Page 18: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/18.jpg)
D. Lipids• Broad group of organic compounds that
dissolve in oily solvents (e.g. acetone, or benzene) and alcohol but generally do not dissolve in water
• Mostly composed of carbon and hydrogen
![Page 19: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/19.jpg)
D. Lipids• 1. Best known lipids are fats
– serve living organisms as important energy sources
– consist of glycerol and up to three long-chain fatty acids
• 2. Modified fats called phospholipids are the major components of membranes
• 3. Other types of lipids include waxes and steroids
glycerine fatty acid
![Page 20: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/20.jpg)
Fatty Acids + Glycerol
![Page 21: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/21.jpg)
Fats
![Page 22: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/22.jpg)
Other important lipids you should know!
Steroids such as cholesterolPhospholipids
![Page 23: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/23.jpg)
I. MICROBIAL PHYSIOLOGY
• _____________: the sum of all biochemical processes taking place in a living cell. Two phases:
• _____________: constructive metabolism; the synthesis reactions; small molecules bonded into larger molecules; energy is “used up”
• _____________: destructive metabolism; decomposition reactions; large molecules split into smaller molecules; energy is released
![Page 24: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/24.jpg)
![Page 25: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/25.jpg)
![Page 26: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/26.jpg)
A._________
• the enzymes present in an organism determine the nature of its physiology
• enzymes are biological catalysts (catalysts are agents that speed up chemical reactions)
• Enzymes “are reusable protein molecules that brings about a chemical change while remaining unchanged itself”
![Page 27: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/27.jpg)
________________= the amount of energy required to do the reaction
![Page 28: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/28.jpg)
Without enzyme
lactose
With enzyme
lactose glucose + galactose
activation energy without enzyme
net energy released
glucose + galactose
activation energy with enzyme
net energy releasedfrom splitting of lactose
Activation Energy = the amount of energy required to do the reaction
![Page 29: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/29.jpg)
Enzymes __________ = what the enzymes works on
________ = what is made
![Page 30: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/30.jpg)
Enzymes
Competitive Inhibitor Noncompetitive inhibitor
Active Site Allosteric Site
![Page 31: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/31.jpg)
Action of enzyme inhibitors
Examples of inhibitors:
1. Competitive=sulfa drug (sulfanilamide)
2. Noncompetitive=Certain poisons, such as cyanide and fluoride (enzyme poison in bacteria)
![Page 32: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/32.jpg)
Factors influencing enzyme action:
• a. Terms:• optimum: the environmental state where the
enzyme works the fastest.• maximum: The maximum environmental limit
where the enzyme works at all.• minimum: The minimum environmental limit
where the enzyme works at all.• e.g. temperature: every enzyme has its optimum
temperature (where it works fastest). Curve is unusual:
![Page 33: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/33.jpg)
enzyme activity vs temperature
![Page 34: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/34.jpg)
pH• Measurement of acid/base balance
• Logarithmic scale• 0-6.9 = acid• 7.1-14 = basic
(alkaline)• 7 = neutral
(like pure water)
![Page 35: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/35.jpg)
enzyme activity vs pH• every enzyme has its optimum pH (where
it works fastest). Bell curve
![Page 36: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/36.jpg)
Naming of enzymes
• names end with -ase• name of substrate + ase
e.g. sucrose is digested by sucrase• kind of reaction + ase
e.g. an enzyme that causes oxidation is called oxidase
![Page 37: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/37.jpg)
Types of Enzymes based on location
• endoenzymes: remain inside of the cell (work internally)– enzymes of cellular metabolism– vulnerable enzymes
• exoenzymes: released to the exterior of the cell (work externally)– digestive enzymes and enzymes of virulence
![Page 38: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/38.jpg)
Constitutive vs Induced Enzymes
• ___________ enzymes: – always present– necessary for life of cell
• __________ enzymes:– produced only when substrates are present– e.g. digestive enzymes – provide efficiency and adaptability
![Page 39: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/39.jpg)
B. Energy and ATP• Energy released from catabolism of foods is stored in a
compound called ATP (adenosine triphosphate)• a molecule of ATP acts like a portable battery—it’s instant
energy for a cell to use• ATP molecules are used everywhere in a cell to meet
energy needs. (When the supply is exhausted, the cell dies)
![Page 40: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/40.jpg)
ADP + Phosphate + Energy = ATP
captures heat releases heat
![Page 41: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/41.jpg)
ATP• Although ATP molecules are used everywhere in the
cell to meet energy needs, they are not suitable for storing energy. The molecules are large and bulky, and surplus takes up too much space in a cell.
• Therefore, cells synthesize or obtain small molecules such as glucose or lipids for energy storage. When needed, these energy storage molecules can be converted to ATP!
• glucose is a principle source of energy for ATP production.
![Page 42: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/42.jpg)
C. Pathways of Energy Production• Most of a cell’s energy is produced from
carbohydrate catabolism • Glucose is the most commonly used
carbohydrate:
• C6H12O6 + 6 O2 + 38 ADP + 38 P 6 CO2 + 6 H2O + 38 ATP
![Page 43: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/43.jpg)
• To produce energy (ATP) from glucose, microbes use 2 general processes:– 1. respiration
• in which glucose is completely broken down– 2. fermentation
• in which glucose is partially broken down
• Both processes usually start with the same first step (glycolysis), but follow different subsequent pathways
![Page 44: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/44.jpg)
Glycolysis• the first stage in the breakdown of glucose
glucose
2 pyruvic acid
(energysource )
series of controlled reactions releasing a
little ATP
![Page 45: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/45.jpg)
![Page 46: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/46.jpg)
Overview of Respiration & Fermentation
glycolysis
respiration fermentationpathwayspathways
Aerobic=CO2 + H2O + 38 ATP an organic end-product
(like alcohol or lactic acid) with low ATP yield
![Page 47: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/47.jpg)
Classification of organisms by oxygen use (study table 6.1)
• 1. obligate aerobes: (= strictly aerobic): must have oxygen to grow (go dormant without oxygen)
• 2. microaerophiles: grow best at low oxygen levels (less than atmospheric)
• 3. facultative anaerobes: use oxygen if it’s present, but can also grow anaerobically (capable of growing at any oxygen level, but greater growth with oxygen present)
• 4. aerotolerant anaerobes: never use oxygen, but not inhibited by it
• 5. obligate anaerobes: grow only in absence of oxygen (inhibited by oxygen)
Good Essay Question! (This or the picture or BOTH)
![Page 48: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/48.jpg)
Growth at different oxygen levels
![Page 49: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/49.jpg)
E. Growth at different temperatures
• Each species has different temperature requirements• minimum growth temperature: lowest temperature at which
growth will occur (very slow growth at this temp)– below the minimum, most microorganisms go dormant,
but do not die• optimum growth temperature: temp at which most rapid
growth occurs• maximum growth temperature: highest temp at which
growth occurs– above this temp, enzymes are denatured and death
might occur• NOTE: Growth parallels rate of enzyme activity.
![Page 50: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/50.jpg)
Growth speed vs temperature
Gro
wth
Sp
eed
![Page 51: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/51.jpg)
F. Classification by temperature requirements
• _____________ (= cryophiles): cold-loving organisms; have optimum growth temp below 25° C
• _____________ (meso = middle): have optimum of 25-40°C
• ____________: heat-loving organisms; have optimum > 40°C
• ______________: growth range = 70-105oC; optimum > 90oC
mesophiles
hyperthermophiles
Good Essay Question Also!
![Page 52: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/52.jpg)
Growth versus temperature
![Page 53: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/53.jpg)
![Page 54: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/54.jpg)
![Page 55: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/55.jpg)
Does size of pan (with same volume) matter?
![Page 56: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/56.jpg)
G. pH and microbial growth
• every organism has its minimum, optimum, and maximum growth pH
• microorganisms often change the pH of their environment– usually create acidity– sometimes create alkalinity
Gro
wth
spe
ed
![Page 57: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/57.jpg)
Thus, the requirements for bacterial growth include:
• Physical aspects– Temperature– pH– Osmotic pressure
• Chemical aspects– Carbon, nitrogen, sulfur, phosphorus, trace
elements, oxygen, and organic growth factors
![Page 58: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/58.jpg)
H. Bacterial fission (cell division)
• less complex than mitosis (division of eucaryotic cells)– only one chromosome
• Binary fission (see figure 6.12)
![Page 59: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/59.jpg)
Remember...• When we talk about microbial growth, we
are really referring to the number of cells, not the size of the cells.
• Microbes that are “growing” are increasing in number, accumulating into clumps of hundreds, colonies ( can be seen with naked eye ) of hundreds of thousands, or populations of billions.
![Page 60: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/60.jpg)
How do we measure microbial growth?
• Plate counts and serial dilutions– We’ll do as part of the microbiology of water and milk lab– See figure 6.16
• Filtration– We’ll do as part of the microbiology of water lab– See figure 6.18
• Direct Microscopic Count– See figure 6.20
• Turbidity– Using the spectrophotometer– See figure 6.21
• Dry weight
![Page 61: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/61.jpg)
I. Population dynamics
• potential populations:– huge– doubling time of 20-30 minutes for many
microorganisms– from 1 cell to over a million in 10 hours (with 30
minute generation)– See figure 6.13 & 6.14
• populations are self-limiting– depletion of food supply– accumulation of toxic metabolic wastes
![Page 62: Microbial Metabolism & Growth](https://reader035.vdocuments.us/reader035/viewer/2022062410/56816547550346895dd7bf44/html5/thumbnails/62.jpg)
• population growth curve
lag phase:slow growth
logarithmic (log)phase: rapid growth
maximumstationaryphase (aging population)
death phase:rapid decline
survivor phase
time