Bact. Lecture 22
a. Scientist named Werner Arbor observed that not every phage could grow on
every bacterial cell. There were problems involved. Also found that could
rescue some phage. Called his observations restriction and modification.
Bact. Lecture 23
o Factors - Time - More time you expose an organism to disinfecting agent,
the more effect it will have.
o Log # survivors
o Temp- As temperature increases, amt of killing increases.
o Concentration - Hig
Bact. Lecture 9
Number of factors that affect bacterial growth:
Temperature- If plot growth rate as function of increasing temperature, have a
bell shaped curve. Have a growth range between the maximum and minimum
growth temperatures. Beyond max and mi
In the real world, bacteria exist for the most part in the form of biofilms.
Biofilm- Flat thick growth on a surface. Bacteria in the real world dont live
freely swimming in individual cells, live on a film. The surface
THE CELL MORPHOLOGY AND PHYSIOLOGY
II. Comparison of prokaryotic and eukaryotic cell structure
III. General features of bacterial cells and colonies
IV. The Gram stain
V. Anatomy and cytology of the bacterial cell
A. The Cytoplasmic Membra
inserts into cell
Soap fits into
Phenol = toxic.
that are less toxic
New York College of Podiatric Medicine
53 East 124th Street, New York, NY 10035
PATHOGENIC MECHANISMS AND HOST RESPONESES
I. Routes of entry
III. Active mechanisms
IV. Passive mechanisms
A. Avoiding phagocytosis
B. Avoiding antibodies
V. Other mechanisms
VI. Host response
A. Innate responses
I. Introduction. The strategy of chemotherapy: consider the three fold interaction of drugmicrobehost.
A. Microbe vs. Host
2. Toxin production
B. Host vs. Microbe
1. Innate immunity
2. Adaptive immuni
STERILIZATION AND DISINFECTION
INHIBITION AND KILLING OF MICROORGANISMS
I. A. Definitions
3. Germicidal agents
4. Antiseptic agents
II. B. Factors Affecting Sterilization
1. Cell wall damage
II. Structure of DNA
Organization of the genome
V. The genetic code
A. Mutations base substitution, frameshift
B. Mutagens physical, biological, chemical
NUTRITION OF BACTERIA
I. Basic nutritional requirements
1. Requirements: Carbon, Nitrogen, Phosphorus, Sulfur, Inorganic Ions
2. Minimal vs. enriched media
B. The role of exoenzymes
C. Nitrogen and Sulfur utilization
Bact. Lecture 25
a. Antimicrobial agent vs. Antibiotic
i. Antimicrobial agent - General, includes drugs chemically synthesized
ii. Antibiotic More specific, refers only to those drugs of microbial
origin. There are some antibiotics produced by bacteria su
PHYSICAL AND CHEMICAL FACTORS AFFECTING GROWTH
I. Reasons For Study
A. Understanding growth in culture and in the body
B. Understanding how to kill undesirable bacteria
A. Growth Temperature Range
Minimum, maximum and optimum
Bact. Lecture 27
For each drug know mechanism, side effect, spectrum, resistance mechanisms
a. Antibiotics that work by competitive inhibition
i. E+S = ES = E + P or E + I = EI
ii. Reverse - can overcome by supplying more substrate. Alternatively,
Bact. Lecture 29
Bioterrorism- Intentional use of microorganisms and toxins of microbial, plant,
or animal origin to produce disease and/or death in humans, livestock, or crops.
a. Why turn to bioweapons?
i. Low production cost- In comparison to nuclea
Bact. Lecture 26
i. Inhibits mitosis of eukaryotes (fungi)
ii. Fights fungus of hair, skin, and nails. Attacks
ii. Antibiotics that affect RNA synthesis
1. RNA polymerase consists of core enzyme, a multisubunit
Bact. Lecture 28
a. Transmissioni. Clinical manifestations- Vibrio Cholerae- Transmitted by diarrhea.
Intestinal organism that causes diarrhea. Someone ingests it and
passes it on. Also want to consider role of see food. Have wate
Bact. Lecture 24
2. Oxidizing agents
Iodine - Famous as skin disinfectant.
Betadine - Is iodine + surface active agent
Chlorine - Famous as water disinfectant. Active agent is HOCl.
This oxidizes, acts as oxidizing agent. In that fashion di
Bact. Lecture 21
a. Transposable elements- In bacteria there are segments of DNA that have
ability to move from one location to another on the same chromosomes or
even to a different chromosome. Essential elements called insertion
sequences are sections o
Bact. Lecture 20
Regulation at the level of translation - This is to say whether RNA will
function or not.
a. Riboswitches- Focusing on mRNA. The story of riboswitches involves
observation of small molecules that interact with messenger RNA to
Bact. Lecture 19
i. Physical mutagen1. Have ultraviolet light, causes pyrimidine (usually thymine)
dimers. The emphasis here is on error prone repair. Now we
are looking at thymine dimers looking at their repair through
error prone mechanisms
Bact. Lecture 18
i. Timing of replication- If replication occurs too soon or have too many
this is a problem. If too soon will have too many copies. IF too late
septum chops Key idea is that this involves methylation.
1. Start of replication site is oriC,
Bact. Lecture 17
a. Lysine Decarboxylation
i. Lys in presence of LDC produces Cadaverine.
Orn in presence of ORN produces putreseine.
Medium used is high lys + dye. If has the
enzyme, produces alkaline material that changes
color of medium from yellow to
Bact. Lecture 15
a. Catabolism Breakdown.
b. Anabolism - Synthetic reactions
c. Amphibolic - A pathway that can be considered catabolic or anabolic
depending on POV. Amphibolic pathways are usually central pathways. If
POV is breakdown of glucose, then gl
Bact. Lecture 16
i. Preservation of bacterial cultures
1. Freezing- -20- -30 Celsius. Can get ultracold freezer with
liquid N2. When we spoke about freezing last time we were
talking about freezing down to ice.
2. Lyophilization- Good for long term preser
Bact. Lecture 14
a. What kind of carbon sources can bacteria utilize?
i. Anything that can feed directly into a central pathway.
1. Bacteria can grow on glucose, lactose (split into glucose +
galactose), fructose, glycerol (converted to DHAP), pyruvate
Bact. Lecture 13
Exam Four Material Start
What do bacteria need for life and growth?
a. Need source of carbon.
i. Provides energy source
ii. Provides backbone for small molecules
b. Source of nitrogen- Have many nitrogen containing compounds in the cel
Bact. Lecture 12
Moisture as it effects growth rate
a. Bacteria require 95% water - This is to say that even on solid medium isnt
totally dry. There is plenty of water on the plate. Yeast- 75% Fungi-50%
Bacteria growing on the surface of the skin - fai