KINGDOM MONERA
(BACTERIA)
What makes this kingdom unique?
 Most abundant organisms on Earth
 Outnumber all other organisms combined
 More in a handful of dirt than the total number of
people who have ever lived
Characteristics
Prokaryotes: no nucleus or membrane-bound organelles
Characteristics
eukaryotes
prokaryotes
smaller than
 Smaller than smallest eukaryotes
 All are unicellular
 Now considered two kingdoms:
Archaebacteria and Eubacteria
KINGDOM ARCHAEBACTERIA
 Archae = ancient
 Evolution considers them the first organisms
 Can live where no others can
Types of Archaebacteria: methanogens
 Convert CO2 into methane gas
 O2 is poison to them
 Require anaerobic conditions
(i.e. sewage or swamp)
 Thrive in cow and human intestines
Types of Archaebacteria: thermoacidophiles
 Love hot and acidic environment
 Many are chemosynthetic
volcanic vents
hydrothermal vents
Types of Archaebacteria:
extreme halophiles
 Salt-loving
 Great Salt Lake and Dead Sea
 Use salt to generate ATP
KINGDOM EUBACTERIA
 Classified in two ways: shape and stain
 3 different shapes
 Unicellular or colonies
1. SPHERE-SHAPED: COCCUS
Diplococcus - two
Staphylococcus –
clusters
Streptococcus –
strings
2. ROD-SHAPED: BACILLUS
Diplobacillus - two
Streptobacillus - strings
3. CORK SCREW: SPIRILLUM
REACTION TO STAIN
 Gram stain used for classification
 Differing reaction based on cell wall
Cell membrane
(Phospholipid)
Peptidoglycan
(Protein + sugar)
Lipopolysaccharide
(Fat + sugar)
Gram-negative
Gram-positive
GRAM-POSITIVE EUBACTERIA
 Absorb Gram stain and appear purple
 Simple cell wall
antibiotics are effective
GRAM-NEGATIVE EUBACTERIA
 Do not absorb Gram stain
 Absorb a secondary pink stain
 Complex cell wall
antibiotics are ineffective
ALEXANDER FLEMING - 1928
 Scottish bacteriologist
 Grew Staphylococcus bacteria in dish
 Contaminated by Penicillium mold
 Mold inhibited the bacteria
1st antibiotic
ANTIBIOTICS
 Fight pathogens
 Interfere with formation of cell walls
 Many obtained from bacteria or fungi
 Others produced synthetically
NATURAL BODY DEFENSES
1.
2.
3.
4.
5.
6.
SKIN
MUCUS
TEARS
STOMACH ACID
LEUCOCYTES
ANTIBODIES
CELLULAR RESPIRATION
1. Obligate aerobes require oxygen
(i.e. Mycobacterium tuberculosis)
2. Facultative anaerobes can use oxygen
when available but do not require it
(i.e. Escherichia coli)
3. Obligate anaerobes cannot grow in
the presence of oxygen
(i.e. Clostridium tetani)
BACTERIA IN NATURE ~
Photosynthesis
 Cyanobacteria are photosynthetic
O2
 Availability of O2
advent of aerobic organisms
Oscillatoria
Nostoc
Anabaena
BACTERIA IN NATURE ~
Nitrogen fixers
 Rhizobacteria grow in roots of soybeans, alfalfa
 Convert atmospheric N2 into usable form for plants
BACTERIA IN NATURE ~
Decomposers
 Break down matter into simpler substances
 Nutrients released into the soil
BACTERIA IN NATURE ~
Living Together (Symbioisis)
 Mutualism: both
organisms benefit
 Bacteria and
Komodo dragons
 Bacteria-laden
saliva
 Mouth provides
habitat
BACTERIA IN NATURE ~
Eutrophication
Excess phosphates and nitrates
Cyanobacteria thrive
Death and decomposition
Decomposition requires oxygen
Fish kill
BACTERIA and INDUSTRY ~
Food Production
 Ferment lactose in milk
sour cream, yogurt, and buttermilk
 Digest protein in milk
ricotta cheese and cottage cheese
 Fermentation
pickles and sauerkraut
BACTERIA and INDUSTRY ~
Genetic engineering
 Insert genes into bacteria
 Develop medical products
(i.e. synthetic insulin)
 Develop disease-resistant crops
(i.e. Bt corn)
Bt Corn



Bt is a naturally-occurring soilborne bacterium that is found worldwide. This bacterium
produces crystal-like proteins that selectively kill specific groups of insects. Once the
protein is eaten, insects stop feeding within two hours of a first bite and, if enough toxin is
eaten, die within two or three days.
Plant geneticists create Bt corn by inserting selected exotic DNA into the corn plant's own
DNA.
Bt corn improves European corn borer control.