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384 terms

Microbiology (Exam 1)

Study of small forms of life
The unit of measure of bacteria
Micron | Micrometer | 10^-6m
Shapes of bacteria
1. Cocci | 2. Rod | 3. Spiral or Spirochetes
Study of heredity or genes
Study of fungi
Study of protozoa
Study of viruses
Study of the immune system
Size of Cocci Bacteria
0.5 to 2 Microns
Size of Rod Bacteria
1 by 3 Microns
Size of Spiral Bacteria or Spirochetes
1 by 600 Microns
Characteristics of Protozoans
1. Kingdom: Protista | 2. Single Cell Animals | 3. Advanced Cell | 4. Eucaryotes | 5. Lack Cell Wall | 6. Saprophytes (98%) | 7. Pathogens (2%)
Characteristics of Algae
1. Kingdom: Protista | 2. Eucaryotes | 3.Photosynthesis | 4. Cell Wall Present | 5. Non-pathogens
Characteristics of Fungi
1. Two Types: Mold and Yeast | 2. Kingdom: Fungi | 3. Eucaryotes | 4. Non-photosynthetic | 5. Saprophytes (98%) | 6. Pathogens (2%)
Characteristics of Mold
1. Multicellular | 2. Some have Septate Hyphae | 3. Mycelium (Colony)
Characteristics of Yeast
1. Unicellular
Characteristics of Bacteria
1. Kingdom: Prokaryotae or Monera | 2. Procaryotes | 3. Saprophytes (96%) | 4. Pathogens (4%)
Characteristics of Viruses
1. Size: Nanometer (10^-9m) | 2. Non-Cellular | 3. Lacks: cell membrane, cytoplasm, nuclear apparatus, enzymes, ATP | 4. Non-living | 5. Kingdom: None
Parts of a Virus
1. Capsid | 2. Nucleic Acid (RNA or DNA - NOT both) | 3. Envelope (Host Cell Membrane - Optional)
Characteristics of Prions
1. Naked free proteins | 2. (I.E.) Mad Cow Disease
Characteristics of Eucaryotes
1. Advanced Cell | 2. Membrane Bound Organelles | 3. Size: Millimeters | 4. Reproduction: Mitosis and Meiosis | 5. Nucleus - membrane bound
Characteristics of Procaryotes
1. Primitive Cell | 2. Lack Organelles | 3. Reproduction: Amitosis | 4. Size: Microns
Converts organic (living or once-living) material into organic material (nonliving); recycles nutrients
Why are microbes ideally suited to demonstrate principles of biology?
1. Easily grown in small test tubes and flasks | 2. Low maintenance (economical) | 3. Growth rate: Quick; ex. E. coli - 17 minutes | 4. Metabolism: similar to higher plants and animals; ex. fermentation
Septate Hyphae
Microscopic filaments in some mold cells
Colony of mold
1. 13th century philosopher | 2. Disease - punishment from God or Gods
Robert Hooke
1. Coined term 'Cell' from viewing cork
Van Leeuwenhoek
1. Father of microbiology | 2. Developed first true microscope (400x) | 3. Observed pond water; "Animalcules"
Spontaneous Generation Theory
1. Life arises from non-life | 2. "Vital Force" need in air
Francesco Redi
1. Against spontaneous generation theory | 2. Experiment: Two jars each with meat. One jar is covered with gauze, other jar is uncovered. Jar with gauze did not have maggots. jar without gauze had maggots. No vital force due to gauze
John Needham
1. Supported spontaneous generation theory. | 2. Experiment: Broth in a capped flask is boiled. Broth is transfered to another flask. Microbes grows in broth because of contamination.
1. Against spontaneous generation theory. | 2. Experiment: Broth in a capped flask is boiled. Cooled down with cap. Result: sterile broth. No "vital force" able to enter broth.
Louis Pasteur
1. Removed spontaneous generation theory. | 2. Experiment: Broth in flask with long curved neck that is open to air is boiled and cooled down. Broth remains sterile because microbes are not able to pass curved neck. | 3. Developed biogenesis | 4. Developed aseptic technique | 5. Ubiquity of microbes: microbes found everywhere
Life from life
John Tyndall
1. Developed method of sterilization called Tyndallization | 2. Bacteria can exist in two forms: spores and vegetative cells
Procedure: boil nutrient solution for 1 hour on three consecutive days. Exospores that survive from boiling in the 1st and 2nd day germinate into vegetative cells. After the 3rd day, any remaining exospores would have germinated and killed with boiling on the 3rd day.
Germ Theory of Disease
Microbes may cause disease
John Lister
English doctor who soaked surgical instruments in a disinfectant | Rate of infection went down | * Applied germ theory of disease to surgery
Science dealing with the classification of living organisms
Refers to a system by which organisms are classified
General Characteristics (Plant Kingdom, Animal Kingdom)
Scientific Name
Genus and species (ex. Escherichia coli)
Specific type of a species (ex. Escherichia coli B)
Binomial System
Double name | Rules: Underline Genus and species, Capitalize Genus name only, small letter for species name
Criteria used to classify Bacteria
1. Morphology (structure) Ex. Cocci, Rod, Spiral shaped | 2. Genetic similarities (DNA, RNA) | 3. Physiological (Biochemical) Characteristics
Biochemical Test
Based upon the ability of a specific microbe to produce a specific enzyme | Ex. E. coli and Shigella produce Amylase | Enzymes are created by RNA and RNA are created by DNA | If two Bacteria produce the same enzyme, then they are related
What is used to make RNA?
Classical Approach
Biased, indirect approach | Based on some characteristics are more important than others (biased) | Ex. Phenotype characteristic and Physiological characteristics (Biochemical test)
Numerical Taxonomy Approach
Unbiased approach | Uses a Similarity Coefficient (% Similarity) |
% Similarity Equation
(Number of Similar Characteristics / Total Number of Characteristics Tested) x 100
Criteria: Cell (Microscopic) Morphology
1. Shapes | 2. Sizes | 3. Arrangement of cells | 4. External and internal structures
Criteria: Macroscopic Morphology
Colony size, appearance
First Step in bacteria identification
Differential Staining (Gram Stain, Acid-Fast Stain)
Criteria: Mode of Obtaining Energy
Phototrophs, Chemotrophs
Criteria: Carbon Source
Organotroph, Lithotroph
"Cold Loving" | 15C-20C | Ex. Marine bacteria, Red algae
"Middle Loving" | 35C-40C | Ex. Pathogens
"Heat Loving" | 50C-60C (Boiling water) | Ex. Archaeobacteria
Criteria: Oxygen Requirements
Aerobic: 16% | Microaerophilic: 6-10% | Facultative Anaerobe: 0-21% | Anaerobes: 0%
Criteria: Metabolic/Biochemical Characteristics
Based on the ability of a microbe to synthesize or not synthesize a specific enzyme
Criteria: Serology
Science that deals with blood serum (Antibodies) and immunology
Serum proteins produced by body after exposure to antigens which bind specifically to those antigens
Anything foreign to body and stimulates production of antibodies | Microbes are antigens
Agglutination Reaction
Positive test of unknown bacteria plus known antiserum (antibodies)
Criteria: DNA Base Composition
% G-C Ratio | Determine the % Guanine-Cytosine nitrogen base composition of DNA | Theory: Similar organism have similar genes and therefore similar % G-C ratios
% G-C Ratio Equation
%G-C Ratio = ((G-C) / ((G-C) + (A - T))) x 100
Criteria: DNA Hybridization
Determine the sequences of Nucleotide Bases | Similar organisms have similar sequences of nucleotide bases
DNA Hybridization Procedure (One type of DNA)
Heat DNA (complementary DNA strands break apart (denatured), hydrogen bonds are broken | Cool DNA (two DNA strands associate, Double helix reformed due to complementary base pairing)
DNA Hybridization of Two types of DNA
If two organisms are related, then the sequence of bases on each DNA molecule will be complementary to each other and the two different DNA molecules will reassociate as a double helix
DNA Probes
DNA fragments tagged with radioactive isotopes or fluorescent dyes
Criteria: Bacterial Recombination (Sexual Conjugation)
Exchange of DNA (plasmid) from one bacteria to another through a pili | Theory: Common to closely related organisms
Criteria: Ribosomal RNA Base Sequencing
Sequence of r-RNA nucleotide bases reflects sequence of bases on DNA molecule
Criteria: Amino Acid Sequences
Amino acid sequence of the same protein take from two different microbes reflect sequences of bases on the different DNA molecules
Criteria: Protein Analysis
Characteristic pattern of cell's proteins compared to other cells protein profile
Criteria: Fatty Acid Analysis
Analysis of fatty acids in cell wall, cell membrane, and as waste products | Fatty Acid Profile
Kingdom Classification
1. Monera/Procaryotae | 2. Protista | 3. Fungi | 4. Plantae | 5. Animalia
Bergey's Three Kingdom Classification
1. Procaryotae (Div I: Blue-Green Algae/Cyanobacteria, Div II: Eubacteria and Archaeobacteria) | 2. Plantae (Fungi, True Algae) | 3. Animalia (Protozoans)
Types of Spirochetes
* Treponema pallidum
Characteristics of Spirochetes
Gram Negative | Aerobic - Facultative Anaerobes | 3 to 600 Microns | Motility: Axial Filament | * Chemoorganotrophic, Phatogenic
Axial Filament
Motile by corkscrew motion and flexing
* Disease caused by Treponema pallidum
Types of Spiral and Curved Bacteria
Spirillum | Campylobacter fetus
Characteristics of Spiral and Curved Bacteria
Gram Negative | Microaerophilic | 0.5 to 60 Microns | Motility: Monotrichous, Lophotrichous, Amphitrichous | * Chemoorganotrophic, Saprophytic, Phatogenic
* Single Flagella
* Tuft of Flagella at one end
* Flagella at both ends
Diseases caused by Campylobacter fetus
Cause miscarriages in humans | Enteritis (food poisoning, turkey meat)
Food poisoning
Types of Gram Negative Aerobic Bacteria
Pseudomonas aeruginosa | Neisseria gonorrheae | Neisseria meningitidis | Francisella tularensis | Brucella abortus | Bordetella pertussis
Characteristics of Pseudomonas
Aerobic | Rods | Motility: Monotrichous | Chemoorganotrophic | Ubiquitous | Fastidious | * Produce pyocyanin
Diseases caused by Pseudomonas aeruginosa
3rd degree patients - No "Get well flowers" | Causes ear infections, eye infections, nosocomial infections, urinary tract infections, respiratory infection (trachea), septicemia (blood infection), meningitis
Nosocomial Infections
Hospital acquired infections
Blue - Green pigment | Produced by Pseudomonas aeruginosa
Characteristics of Neisserias
Microaerophilic | Cocci (single, pairs, chains) | Chemoorganotrophic | Fastidious
Disease caused by Neisseria gonorrhoeae | Inhabits urogenital tract (mucus membrane) | STD/STI
Disease caused by Neisseria meningitidis | Inhabits upper respiratory tract (mucus membrane)
Characteristics of Francisella tularensis
Gram Negative | Aerobic | Pleomorphic Rods | 0.2 Microns (smallest bacteria) | * Chemoorganotrophic
Disease caused by Francisella tularensis | "Hunter's disease", 105F fever, swollen lymph nodes | * Transmission: contact w/ blood, penetrates small cuts and pores of skin; from infected animals or vectors (ticks, mosquitos, deer flies)
Characteristics of Brucella abortus
Gram Negative | Aerobic | Short rods | Chemoorganotrophic | * Pathogens of reproductive and GI tract
* Disease caused by Brucella abortus | "Undulant Fever" in humans
Characteristics of Bordetella pertussis
Gram Negative | Aerobic | Short rods | Chemoorganotrophic | * Pathogens of respiratory tract
Whooping cough
* Disease caused by Bordetella pertussis
Types of Gram Negative Facultative Anaerobic Rods
Escherichia | Enterobacter | Serratia | Salmonella | Shigella | Proteus | Vibrio | Yersinia
Characteristics of Escherichia
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | *Opportunistic Pathogen
Characteristics of Enterobacter
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | *Opportunistic Pathogen
Characteristics of Serratia
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | *Opportunistic Pathogen
Characteristics of Proteus
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | *Opportunistic Pathogen
Diseases caused by Escherichia coli
Urinary tract infection | Peritonitis | Gastroenteritis (food poisoning) | Diarrhea | Nosocomial infections | Enterohemorrhagic strain
Characteristics of Yersina
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Fleas on Rodents| * Pathogen
Characteristics of Salmonella
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | * Pathogen
Characteristics of Shigella
Gram Negative | Small Rod | Peritrichous flagellation or nonmotile | Chemoorganotrophic | Facultative anaerobes | Ferments carbohydrates | Coliform | Transmission: Oral-fecal, food/water borne | * Pathogen
Bubonic Plague
Disease caused by Yersina pestis | "Black Death" | * Mortality Rate: 70%
Pneumonic Plague
Disease caused by Yersina pestis | Mortality Rate: 100%
* Disease caused by Salmonella enteritidis (from chicken) or Vibrio parahaemolyticus (from seafood)
Typhoid Fever
* Disease caused by Salmonella typhi
Bacillary dysentery
Disease caused by Shigella dysenteriae | Ulcerated colon | * Bleed out in 2 days
Characteristics of Vibrio
Gram Negative | Short, straight or curved rod | Monotrichous flagella } Chemoorganotrophic | Facultative anaerobes | Occurs in fresh and salt water and GI tract of humans and animals
Disease caused by Vibrio cholerae | Bacteria coats intestinal lining causing diarrhea, dehydration, and electrolyte loss | Death from cardiovascular disease | Loss of 20 liters of liquid per day
Types of Anaerobic Gram Negative Rods
* Bacteroides
Characteristics of Bacteroides
Gram Negative | Anaerobic | Pleomorphic rods | Peritrichous flagellation | Chemoorganotrophic | Most numerous in intestine | * Transmission: Internal wounds: knife, gunshots, ulcers
Diseases caused by Bacteroides fragilis
Abscesses and bloodstream infections | Peritonitis
Disease caused by Bacteroides fragilis | It is an inflammation of the peritoneum, the tissue that lines the wall of the abdomen and covers the abominal organs
What group of bacteria is the smallest?
Rickettsias and Chlamydias | 0.2 Microns to 0.1 Microns
Characteristics of Rickettsia
Gram Negative | Pleomorphic rods | Nonmotile | Among the smallest bacteria (0.1 to 0.2 Microns) | Fastidious | Obligate intracellular parasites | * Transmission: Insect vector required
Rocky Mountain Spotted Fever
Disease caused by Rickettsia | Transmitted by Insect: Dog or Wood Tick
Epidemic Typhus
Disease caused by Rickettsia | Transmitted by Insect: Lice
Murine Typhus
Disease caused by Rickettsia | Transmitted by Insect: Fleas
Strict Obligate Intracellular Parasite
Requires host cell to reproduce inside of
Various shapes and sizes
Characteristics of Chlamydia
Gram Negative | Pleomorphic rods | Nonmotile | Among the smallest bacteria (0.1 to 0.2 Microns) | Fastidious | Obligate intracellular parasites | Steals energy from host cell | Transmission: Interpersonal contact, Airborne (flies)
Disease caused by Chlamydia trachomatis | Eye infection | * No. 1 cause of blindness in the world
Chlamydial Infection (STD)
Disease caused by Chlamydia trachomatis | No. 1 STD | * Transmission: Mucus membrane to mucus membrane
Characteristics of Mycoplasma
Naturally lacks cell wall | Gram Negative | Highly pleomorphic | Colony: "Fried Egg" appearance | Saprophytic or Pathogenic | Fastidious
Primary Atypical Pneumonia
Disease caused by Mycoplasma and L-Forms | "Walking pneumonia"
L Forms
Lacks cell wall | Induced in lab with antibiotics | Protoplasts - originally gram positive | Spheroplast - originall gram negative
A type of L-Form bacteria | Originally a gram positive bacteria
A type of L-Form bacteria | Originally a gram negative bacteria
Types of Gram Positive Cocci
Staphylococcus | Streptococcus
Characteristics of Staphyloccus
Gram Positive | Cocci (Clusters, single, pairs, fours) | 1 to 2 Microns | Chemoorganotrophic | * Facultative anaerobe | Habitat: Nasopharynx, Skin
Diseases caused by Staphylococcus aureus
Wound, skin infections | Abscesses | Toxic shock syndrome | Nosocomial infections | * Food poisoning (most common)
Characteristics of Streptococcus
Gram Positive | Chains of cocci | Facultative anaerobe 1 to 2 Microns | * Habitat: Nasopharynx, Urogenital
Strep Throat
* Disease caused by Streptococcus pyogenes
Scarlet Fever
* Disease caused by Streptococcus pyogenes
Rhumatic Fever
Disease caused by Streptococcus pyogenes | Autoimmune disease (Infection of heart valves)
Bacterial pneumonia
* Disease caused by Streptococcus pneumoniae
Methicillin resistant Staphylococcus auerus
Types of Endospore Forming Gram Positive Rods
Bacillus | Clostridium
Characteristics of Bacillus
Gram Positive | Rods in chains| Aerobic | Endospore forming | Chemoorganotrophic | Strict Aerobes - facultative anaerobes | * Habitat: Soil, water
Disease caused by Bacillus anthracis | disease of animals
Pulmonary Anthrax
Disease caused by Bacillus anthracis | Man made disease | * Inhaled spores
Characteristics of Clostridium
Gram Positive | Rods | Anaerobic | Endospore forming | Chemoorganotrophic | Obligate anaerobes | Habitat: Soil, marine/fresh water sediments, intestinal tract of humans and other animals
Disease caused by Clostridium botulinum | Fatal food poisoning | * Neurotoxin
* Disease caused by Clostridium tetani
Gas Gangrene
* Disease caused by Closridium perfringes
Type of Irregular Nonsporing Gram Positive Rods
* Corynebacterium
Characteristics of Corynebacterium
Gram Positive | Rods | Aerobic | Chemoorganotrophic
Disease caused by Corynebacterium diptheriae | Pseudo-membrane blocks trachea | * Toxins
Characteristics of Mycobacterium
Acid Fast Positive | Gram Positive | Rods | Mycolic Acid in Cell Wall | Aerobic | Chemoorganotrophic | * Pathogenic species are fastidious
Disease caused by Mycobacterium tuberculosis | Lung infection but may spread to other vital organs (kidneys, bone tissue)
Disease caused by Mycobacterium leprae | Skin and nervous system disease
Types of Anoxygenic Photosynthetic (Phototrophic) Bacteria
Purple-Sulfur Bacteria | Green-Sulfur Bacteria
Characteristics of Anoyxgenic Photosynthetic (Phototrophic) Bacteria
Gram Negative | Rod | Photolithotrophic | Photosynthetic apparatus: Chromatophores | Pigment: Bacteriochlorophyll and Carotenoid | Accumulates sulfur granules within cell | Releases CO2| Habitat: Aquatic | * Nonpathogenic
Types of Budding And/Or Appendaged Bacteria (Clean Water)
* Caulobacter
Characteristics of Caulobacter
Gram Negative | Rod | Strictly Aerobic| Secrete appendages: Stalk and Holdfast | Chemoorganotrophic | Habitat: Aquatic: Fresh water containing low levels of organic material (clean water) | May clog clean or ultra pure water systems | Biofouling
Types of Sheath Bacteria (Sewage Water)
* Sphaerotilus
Characteristics of Sphaerotilus
Gram Negative | Rod | Sheath, holdfast, stalk | Chemoorganotrophic | Habitat: Aquatic: Fresh water contaminated with sewage or wastewater | May clog sewage/polluted water systems | * Biofouling
* Biological induced problems
Which bacteria has Stalk and Holdfast appendages?
* Caulobacter and Sphaerotilus
Which bacteria has a Sheath, Stalk and Holdfast appendages?
* Sphaerotilus
Types of Gliding Bacteria
* Cytophaga
Characteristics of Cytophaga
Gram Negative | Rods or long filaments | Glide motility | Predatory: "Pathogens of bacteria" | * Chemoorganotrophic
Which bacteria is a pathogen of other bacteria?
* Cytophaga
Types of Archaeobacteria (Archaea)
Methanogens | Halophiles | * Thermophiles
Characteristics of Archaeobacteria
Primitive Bacteria | Diverse: Cocci, Rod, Spirals | Lack Peptidoglycan in cell wall | Unique ribosomal RNA and proteins | Chemolithotrophic | Habitat: Ubiquitous, adverse, harsh, extreme | * Nonpathogens
Type of archaeobacteria that release methane gas
Archaeobacteria that live in extremely salty environment (salt crystals)
Archaeobacteria that live in high temperatures (50-60C)
Types of Oxygenic Photosynthetic Bacteria
Cyanobacteria (Blue-Green Algae)
Characteristics of Cyanobacteria (Blue Green Algae)
No membrane-bound organelles | Presence of Peptidoglycan in cell wall | 5 to 15 Microns | Pigment: Chlorophyll a | Thylakoids (Photosynthetic apparatus) | Reproduction: Binary Fission (Amitosis), Fragmentation, Spores (Akinetes) | Photolithotrophs | Aerobic | Photosynthetic | Nitrogen Fixation (Heterocysts) | Habitat: Aquatic, Fresh and marine water, soil | Symbiotic relationship with fungus (Lichens)
Which bacteria use spores for reproduction?
Cyanobacteria (Blue-Green Algae)
Which bacteria produce Chlorophyll a?
Cyanobacteria (Blue-Green Algae)
Type of Cyanobacteria
Nitrogen Fixation
* Nitrogen (N2) is converted to Ammonia
What is Oxygenic Photosynthesis?
Following photosynthesis, oxygen is released
Types of Procaryotic Cells
Eubacteria | Archaeobacteria (Archaea) | * Cyanobacteria (Blue-Green Algae)
Procaryotic | Largest Group of Bacteria | Most advanced | Peptidoglycan in cell wall
Archaeobacteria (Archaea)
Procaryotic | Primitive Bacteria | Kingdom: Archaea | Unique RNA, Proteins | Habitat: Harsh conditions, boiling water (thermophiles), ice (psychophiles), salt (halophiles) | Lack peptidoglycan in cell wall
Cyanobacteria (Blue Green Algae)
Procaryotic | Undergo Photosynthesis | * Peptidoglycan in cell wall
3 Ways Bacteria Show Motility
Flagella | Axial Filament | * Gliding
Flagella Structure
Thin, long, hair like
Flagella Composition
Flagellin (100% protein)
Function of Flagella
One Flagella on one end
One Flagella on each end
Tuft of Flagella
Flagella all over surface
No Flagella
Methods of Determining Motility
Wet Mount Technique | Motility Media (Stab Culture Method) | * Flagella Stain
Wet Mount Technique
Method for determining motility | Sample on slide | * Disadvantage: exposed to live pathogens
Motility Media (Stab Culture Method)
Method for determining motility | Semi Solid Agar (0.5% Conc) in test tubes | "Fuzzy" result shows motility (Positive test) | Covered test tubes means not exposed to pathogens
Flagella Stain
Method for determining motility | Prepared slides | * Not exposed to microbes (killed microbes) | Disadvantage: 8-12 hours to prepare
Axial Filament
Function: Motility | Protein band around spirochete | Corkscrew motion with flexing | Ex. Treponema pallidum
Function: Motility | Electrostatic propulsion | * Ex. Cytophaga
Fine, hair-like structure with "sticky ends" | Hollow tube | Smaller and more numerous than flagella | Not used for motility
Function of Pili/Fimbriae
Adherence | Transfer of genetic information (chromosome or plasmid) from one cell to another
* Slime layer or Glycocalyx
Function of Capsule
Adherence | Prevents Phagocytosis | Collects nutrients | Removes wastes
Detection of Capsule
Capsule Stain
Function of Cell Wall
Rigidity and shape: protection, strength | Prevents osmotic shock | Anchorage for flagella | Gram Stain (based on lipid concentration of cell wall) | Lipopolysaccharide in Gram Negative bacteria | Site of Action for antibiotics (Ex. Penicillin attacks peptidoglycan in cell wall)
Lipopolysaccharide (LPS)
Found in outer layer of cell wall of gram negative bacteria | causes fever and allergic reactions
Peptidoglycan Unit
Backbone of Cell Wall | Lattice net-like structure
Gram Positive Cell Wall
1% to 4% Lipid | Teichoic Acid | Multilayered, thick (two-thirds peptidoglycan) | Tight rigid lattice network, extensively cross linked | * Many cross bridges between peptidoglycan units
Teichoic Acid
Found in Gram Positive Cell Wall | Acts as a 2nd chemical shield
What is the Lipid % of G+ Cell Wall?
1 to 4%
Gram Negative Cell Wall
10% to 23 % Lipid | Thinner layer (one-quarter peptidoglycan) | Less rigid, looser lattice network | Fewer cross bridges between peptidoglycan units | * Outer layer (Lipoprotein, Phospholipid, Lipopolysaccharide (LPS))
Composition of Outer layer of Gram Neg CW?
Lipoprotein | Phospholipid | * Lipopolysaccharide (LPS)
Purpose of Peptidoglycan Layer?
* Chemical Shield
Which bacteria lacks a cell wall?
Mycoplasma and L-Forms
Which bacteria lacks peptidoglycan units in CW?
Archaeobacteria (Archaea)
Structure of Cell Membrane (Bacteria)
* Phospholipid Bilayer with Protein Gates and Channels
Composition of Cell Membrane
40% Protein | 60 % Lipid
Function of Cell Membrane
Selective semi-permeable membrane (Cell Transport) | Initiates cell division | Site of ATP Synthesis (Infolding of CM) | Site of Photosynthesis (Infolding of CM)
Types of Cell Transport
Diffusion | Osmosis | Passive Transport | Active Transport
Site of Photosynthesis in Photosynthetic Bacteria | Infolding of Cell Membrane
Site of Photosynthesis in Cyanobacteria Bacteria | Infolding of Cell Membrane
Periplasmic Space
Located between cell wall and cell membrane | stores and releases digestive enzymes
* Liquid, viscous fluid that contains and support cellular contents
* Genetic material stored in one, circular, double stranded chromosome
Function of Nucleoid
controls cellular activities | controls reproduction
* Additional circular piece of DNA, self replicating and not essential to the life of the cell
Appears as granules | Responsible for protein synthesis
* Granules (Cytoplasmic inclusions)
Functions as storage | Ex. Starch granules
Most resistant biological structure | Survival mechanism, not a form of reproduction | * Fromed under adverse, harsh conditions
Structure of Endospore/Exospore
Central Core (chromosome) | Cortex (Calcium-Dipicolonic Acid Complex) | * Inner and Outer Spore coat
Calcium-Dipicolinic Acid Complex
composition of cortex of endospore/exospore | Chemical, UV shield
Composition of Spores
Dehydrated (25% less water than vegetative cell) | Dormant (Low metabolic activity) | Calcium-Dipicolinic Acid Complex (Cortex) | Thick Spore Coat
Life cycle of Endospore/Exospore
Sporulation Cycle/Phase | Vegetative Cycle/Phase
Examples of Eucaryotic Cells
Protozoan | Fungi | True Aglae | Higher Plants and Animals
Characteristics of Eucaryotic Cell
More advanced | Organelles | Larger than procaryotic cells | Mitosis and Meiosis
More numerous and shorter | Functions in motility
Cell Wall of Eucaryotes
Gives structure, strength, protection | No peptidoglycan units
Eucaryotes with Cell Walls
Plant cells | Algae | * Fungi
Eucaryotes without Cell Walls
Animal Cells | Protozoans
Structure of Cell Membrane (Eucaryotes)
Fluid Mosaic Model | Phospholipid bilayer with protein molecules | * Sterols
* Complex Lipids
Movement of solutes (particles) from an area of high concentration of solutes to an area of low concentration of solutes through a selective semipermeable membrane | No energy (ATP) required | * No protein gates required
Diffusion of Water | Movement of water from high concentration of water to an area of low concentration of water through a selective semipermeable membrane | No energy (ATP) required | No protein gates required
Less solutes | High concentration of water
More solutes | Low concentration of water
Facilitated Passive Transport (Facilitated Diffusion)
Movement of solutes (particles) from high concentration of solutes to an area of low concentration of solutes using protein gates/channels/carriers through a selective semipermeable membrane | No energy (ATP) required | * Requires Protein Gates
Active Transport
Movement of solutes from an area of low concentration of solutes to an area of high concentration of solutes through a semipermeable membrane | Requires ATP | * Requires Protein Gates
Functions as internal support | Protein microtubules and protein microfilaments
* Intracellular membrane bound structures, that perform specific functions within a eucaryotic cell | Procaryotic cells do not contain organelles
Organelle | contains chromosomes with protein histones | Nuclear membrane | Controls all cellular activities and reproduction
Endoplasmic Reticulum
Organelle | Canals or tubules that run throughout the cytoplasm connecting all interanl cellular components | Rough ER (with ribosomes) | * Smooth ER (without ribosomes)
Function of Endoplasmic Reticulum
Transport | Storage | * Large surface area for chemical reactions (protein synthesis, lipid synthesis)
Golgi Apparatus (Complex)
4 to 8 flattened sacks | Modifies proteins and packages proteins into vesicles
Vesicle (small)
Small membrane bound sacks | Transport and storage
Vesicle (large)
Large membrane bound sacks | Transport and storage
Lysosome Vacuole
"Suicide packets or sacs" | contains digestive lysozome enzymes | Digest worn out or damaged cells | Digest worn out organelles or foreign material that enter cell
"Power house of the cell" | Fat rod-shaped, double membrane, internal membrane called Cristae | * Functions in ATP synthesis
Cylindrical tubes, protein microtubules | Functions in cell division, spindle fibers
Algae and Plants | Photosynthetic pigment | Functions in photosynthesis| Chromatophore and Thylakoids
Cytoplasmic Inclusions/Granules
Glycogen Inclusions | Starch Inclusions | * Fat Inclusions
Dissolved Particles | Ex. Salts, Sugars
* Water (Universal Solvent)
Isotonic Solution
* Solute and solvent concentration of a living cell is equal to the outside solution
What is physiological saline?
A 0.85% salt (NaCl) solution | Isotonic solution
Hypertonic Solution
Solute concentration of an outside solution is greater than the solute concententration of a living cell | If higher concentration of solute outside, water flows out of cell causing Plasmolysis
Cell shrinks due to cell being in hypertonic solution | Water flows out of cell to hypertonic solution
Hypotonic Solution
Solute concentration of an outside solution is lower than the solute concentration of a living cell | If lower concentration of solute otuside, water flows into cell causing Plasmoptysis
Cell bursts due to cell being in a hypotonic solution | Water flows into cell from hypotonic solution
Who developed first true microscope?
Van Leeuwenhoek
What is needed in Spontaneous Generation Theory?
Vital Force
Koch's Postulate
1. Specific causative agent must be found in every case of the disease | 2. The disease's organism must be isolated in pure culture | 3. Inoculation of a sample of the culture into a healthy, susceptible animal must produce the same disease | 4. The disease's organism must be recovered from the inoculated animal
bent rod
Synthesis of mRNA from a DNA template
Disease causing
Acid-Fast Bacteria
Mycobacterium | Cell wall composed of mycolic acid | * Stains gram positive
What is the most resistant biological structure known to humans?
What happens to exospores in optimal condition?
Germinate into vegetative cells
When does vegetative cells form exospores?
During adverse conditions
Ability to make a spore
Exospore turns into a vegetative cell | Requires optimal conditions
How are vegetative cells destroyed?
What does a nutrient broth represent?
Optimal conditions
What happens to vegetative cells in adverse conditions?
Cell Lysis | Exospore released
In Tyndallization, why do vegetative cells not form exospores between day 1-2 and day 2-3?
Not an adverse condition | Exospore formation takes longer than 24 hours.
Who developed asceptic technique?
Louis Pasteur
Silkworm disease caused by Fungi | Showed germ theory of disease
Robert Koch
Gave first proof that microbes can cause disease | Associated Bacillus anthrasis as cause of skin disease, anthrax | * Defined Koch's Postulate
Cell Theory
Cell is basic unit of life | Smallest living unit | * Schleiden and Schwann
Schleiden and Schwann
Formed Cell Theory
Common Theme of Structure
* All living cells must have common characteristics
What are characteristics that all living cells must have?
Cell Membrane | Cytoplasm | Nuclear Apparatus | Four Basic Elements | ATP | Enzymes | * Macromolecules
What are the four basic elements of living cells?
Carbon | Nitrogen | Oxygen | Hydrogen
What are the macromolecules (polymers)?
Protein | Lipid | Carbohydrate | Nucleic Acid
What are DNA and RNA composed of?
Nucleic Acid
Naked, free floating chromosome
Energy molecule
Protein catalyst
Diversity of bacteria
Spore formers | Photosynthetic bacteria | Methanogens | Flagella
How are chemical bonds classified?
By strength of the bonds
Covalent Bond
Sharing of electrons between 2 or more atoms | Associated with organic molecules (ex. Methane (CH4)) | Strong bond | Exception: Water (H20 - inorganic)
Hydrogen Bond
Electrons spends more time with one atom (unequal sharing) | Polarity | Single H-bond is weak | Many H-bond is strong
Ionic Bond
One atom lose an electron while another gains an electron | No sharing of electrons | Associated with inorganic molecules (ex. NaCl) | Weak bond
What chemical bonds are organic molecules associated with?
Covalent bond
Types of Organic Molecule
Protein | Carbohydrates | Lipids | Nucleic Acids | * ATP
Sub-unit of proteins
Amino Acids
Composition of Amino Acids
Central Carbon | Hydrogen | Carboxyl Group (COOH) | Amine Group (NH2) | * R-Group
Carboxyl Group
Amine Group
Function of Protein
Structure Role: strength, support (collagen, keratin) | Energy source (after conversion) | * Enzymatic (most important function)
Organic protein catalyst that speeds up a chemical reaction without being chemically altered
How many types of amino acids?
20 types
"Lock & Key Fit"
Formed between a substrate and an enzyme to create a reaction | Ex. Sucrose (substrate) and Sucrase (enzyme)
Structure of DNA
Double Helix
Composed of two Monosaccharides
Parts of a Nucleotide
Sugar (Deoxyribose) | Phosphate | * Nitrogen Bases (Purines and Pyrimidines)
What gives a Nucleotide its structure?
* Sugar (Deoxyribose) and Phosphate
Nitrogen base group of a nucleotide | Functions as genes | * Adenine and Guanine
Nitrogen base group of a nucleotide | Functions as genes | * Thymine and Cytosine | Note: the 'y' to remember
Replaces Thymine in RNA
What bonds form between Nitrogen base pairs?
Hydrogen bonds
What are the complimentary base pairs?
Adenine = Thymine | Guanine = Cytosine
How many H-bonds between Adenine and Thymine?
Two Hydrogen Bonds
How many H-bonds between Guanine and Cytosine?
Three Hydrogen Bonds
Function of RNA | Protein synthesis
Type of Spiral/Curved Bacteria | Microaerophilic
Type of Spiral/Curved Bacteria | Microaerophilic
Largest RNA
mRNA (messenger RNA)
Single stranded | Function: Protein Synthesis
Three types of RNA
mRNA (messenger) | tRNA (transfer) | *rRNA (ribosomal)
What replaces Thymine in RNA?
Function of Carbohydrates
Source of energy (Glucose) | Storage of Energy (Glycogen, Starch) | Gives Structure (DNA)
Carbohydrates | Storage form of Energy | Animals | Polysaccharides |
Carbohydrates | Storage form of Energy | Plants | Polysaccharides
One simple sugar | Ex. Glucose, Fructose, Galactose
Simple sugar | Monosaccharide
Two monosaccharides | * Ex. Lactose
Disaccharide | * Glucose + Galactose
What chemical bonds for disaccharides?
Covalent bonds
Disaccharide | * Glucose + Fructose
Disaccharide | * Glucose + Glucose
Glycogen | Starch | * Glucose units
Simple sugar | Monosaccharide
Simple sugar | Monosaccharide
Functions of Lipid
Storage form of Energy (converted to glucose) | Structural role (cell membrane - phospholipid)
Two types of lipids
Simple Lipid (Triglycerides) | Complex Lipid
Simple type of lipid
Subunit of lipids
One Glycerol | Three Fatty Acid Chains
Adenosine Triphosphate (ATP)
Energy Currency of Cell | Breaking off of covalent bond of Phosphate releases energy (ATP to ADP)
Hydrogen (H+) ion concentration of a solution
Compound that splits in H2O and releases Hydrogen (H+) Ions | Ex. HCl
Compound that splits in H2O and releases Hydroxyl (OH-) Ions
What chemical bond is broken to release energy from ATP?
Covalent Bond | ATP to ADP
pH Scale
Acidic (0-7) | Basic/Alkaline (7-14) | * Neutral (7)
OH- Ion
What does neutral means on the pH scale?
Hydrogen (H+) ions equals Hydroxyl (OH-) ions concentration
Spores formed by cyanobacteria for reproduction
Energy from light | Carbon source from inorganic materials
Energy from chemical reaction | Carbon source from organic materials
Concentration of Solid Agar
Concentration of Semi-Solid Agar
Give an example of how pili is used by bacteria
Genetic information (R-plasmid) form E. coli that is resistant to antibiotics is transferred to Shigella and it becomes resistant to antibiotics and untreatable
If two organisms are related then the sequences of bases on each DNA molecule will be _____ and _____.
Complimentary to each other | The two DNA molecules will reassociate as a double helix
What chemical bonds are broken in DNA by heat?
Hydrogen bonds
Function of plasmid
Transfer of antibiotic resistant genes | Transfer of new genes
Obtains energy from Light
Obtain energy from Chemical Reactions
Carbon source from organic material
Carbon source from inorganic material
Which is an unbiased approach for bacterial classification?
Numerical Taxonomy Approach
Which is a biased approach for bacterial classification?
Classical Approach
Types of cell morphology
Shapes | Sizes | Arrangement of cells | External and Internal structures
Criteria: Temperature
Psychrophiles | Mesophiles | Thermophiles
Why would DNA that have been denatured reassociate?
Complimentary base pairing
Function of Heterocyst
Nitrogen Fixation | N2 gas to Ammonium (NH4+)