SURVEY OF BACTERIA

1
SURVEY OF BACTERIA

• Taxonomic scheme according to
• Bergey's Manual of Determinative Bacteriology,
  9th ed. and Bergey's Manual of Systematic
  Bacteriology, 1st ed., (2nd edition coming out)

2
The bacteria have been classified according to 4
volumes

• Volume 1 Gram negatives of general, medical or
  industrial importance
• Volume II Gram positives other than actinomycetes
• Volume III Gram negatives with distinctive
  properties, cyanobacteria and
  archaeobacteria
• Volume IV Actinomycetes (Gram positive
  filamentous bacteria)

3

• Each division is divided into sections 33 total
  sections
• Each section may contain several taxonomic
  groupings that are then followed by classes,
  orders, families, genera and species
• Classification of the bacteria has been based
  upon phenotypic characteristics such as
• morphology
• cell wall
• Gram reaction
• oxygen requirements
• spore formation
• cell structures (capsules, sheaths, etc.)
• motility
• reproduction
• growth conditions
• metabolic patterns (oxidative, fermentative,
  photosynthetic, etc.)

4
Bergeys Manual of Systematic Bacteriology 2nd
edition

• 2 domains Archaea and Bacteria
• 25 phyla
• 5 volumes (2 volumes have been published so far)

5

• Volume 1 The Archaea and the Deeply Branching
  and
• the Phototrophic Bacteria
• Volume 2 The Proteobacteria
• Volume 3 The Low G C Gram-Positive Bacteria
• Volume 4 The High G C Gram-Positive Bacteria
• Volume 5 The Planctomycetes, Spirochaetes,
  Fibrobacteres, Bacteroidetes,
  Fusobacteria

6

• Classification is now based on molecular
  characteristics
• Phylogenetic Classification which shows the
  evolutionary relationships between organisms.
• new molecular techniques are able to increase the
  understanding of the relatedness of organisms,
  such as
• DNA base composition - G C
  (G C / G C A T X 100)
• Nucleic acid hybridization
• Nucleic acid sequencing
• RNA sequencing
• Protein sequencing amino acids are direct
  reflections of mRNA sequences
• clinically significant species will not be
  grouped together

7
The basic unit of classification the bacterial
species is defined as

• a collection of strains that share many stable
  properties and differ significantly from other
  groups of strains (subjective definition)
• a more precise definition may be a collection of
  strains that have a similar G C composition and
  70 or greater similarity as judged by DNA
  hybridization experiments
• it should be phenotypically distinguishable from
  other similar species

8

• a strain a population that is distinguishable
  from at least some other populations within a
  particular taxonomic category. It is considered
  to have descended from a single organism or a
  pure culture, though they may vary slightly from
  one another.
• biovars variant stains characterized by
  biochemical or physiological characteristics
• morphovars variant strains that differ
  morphologically
• serovars variant strains that have different
  antigenic properties
• type strain a strain of species

9
BERGEYS MANUAL OF SYSTEMATIC BACTERIOLOGY 1ST
EDITION

• VOLUME 1 - Gram negatives of general, medical or
  industrial importance

10
SPIROCHETES 2nd ed. classified in volume 5
Phylum Spirochaetes

• Gram negative
• helical or spiral shaped
• flexible - can twist or contort their shape
• movement by axial filaments - appearance of
  gliding
• may be anaerobic, aerobic or facultative
• live in all types of environments
• examples
• Treponema pallidum syphillus
• Borrelia burgdorferi - Lyme disease

11
Figure 21.14
12
axial filament complex of axial fibrils
(periplasmic flagella)
Figure 21.15 (a1) and (a2)
13
Lyme Disease

• LD or Lyme borreliosis
• caused by Borrelia burgdorferi, B. garinii, and
  B. afzelii

Figure 38.8 (a)
14
Stages of Lyme disease

• localized stage
• develops 1 week to 10 days after infection
• expanding, ring-shaped, skin lesion
• flu-like symptoms
• disseminated stage
• occurs weeks or months after infection
• neurological abnormalities, heart inflammation,
  and arthritis
• late stage
• occurs years later
• demyelination of neurons, behavioral changes, and
  symptoms resembling Alzheimers disease and
  multiple sclerosis

15
Figure 38.8 (b) and (c)
16
AEROBIC, MICROAEROPHILIC, MOLTILE,
HELICAL/VIBRIOD GRAM NEGATIVE 2nd ed.
classified in volume 2 class 5
Epsilonproteobacteria

• rigid cells (as opposed to spirochetes)
• polar flagella for locomotion

17
Figure 22.27
18
Examples

• Campylobacter jejuni - becoming a more serious
  pathogen recently is being found in milk, water
  and food, esp. a problem in raw milk, carried in
  feces of many animals (humans too) and bird
  guano, low infective dose, so incubation time not
  needed
• Helicobacter peptic ulcers

19
Peptic Ulcer Disease and Gastritis

• caused by Helicobacter pylori
• colonizes gastric mucus-secreting cells
• produces urease, which acts to increase pH
• releases toxins that damage epithelial mucosal
  cells

Figure 38.14
20
GRAM NEGATIVE AEROBIC RODS AND COCCI in 2nd ed.
classified in volume 2 class 3 Gammaproteobacteria
, class 2 Betaproteobacteria, class 1
Alphaproteobacteria

• cocci, straight or slightly bent rods
• require higher concentrations of sodium chloride
• one of the largest and most diverse groups
• oxidase positive

21
Examples

• Pseudomonas - many are a part of normal
  intestinal flora
• Pseudomonas aeroginosa - common cause of ear and
  eye infections, problem in swimming pools and
  spas and hospitals (nosocomial inf.), found in
  solutions, including hexachlorophene soap, dilute
  phenolic solutions and benzalkonium chloride
  solutions
• Neisseria gonorrhoeae - gonorrhea
• Neisseria meningiditis - meningitis

22
Figure 22.24
23

• Azobacter and Rhizobium -
• involved with
• nitrogen fixation
• live in symbiosis
• with plant roots

Figure 22.9
24

• Legionella - found in most water, nosocomial
  infections
• range of respiratory infections, some subspecies
  can be very virulent, all require L-cysteine to
  grow
• Bordetella pertussis - Whooping cough

25
Figure 22.13
26
FACULTATIVELY ANAEROBIC GRAM NEGATIVE RODS
2nd ed. volume 2 class 3 Gammaproteobacteria

• straight rods
• lateral flagella for locomotion
• oxidase negative
• simple nutritional requirements (do not require
  sodium chloride)

27
Examples

• Coliform bacteria - bacteria commonly found in
  mammal intestinal tracts used as indicators of
  fecal contamination
• def. gram negative, non spore forming anaerobic
  or facultatively anaerobic rods which ferment
  lactose with the formation of gas in 48 hrs. at
  35 C
• Fecal coliforms - same def but at 44 C
• Escherichia coli
• E. coli 0157H7 - cause of enterotoxigenic
  infections, highly virulent, widespread

28

• Shigella - bacillary dysentery, low infective
  dose
• Salmonella - 2000 antigenic types, many pathogens
  high infective dose, but new forms with low dose
• Serratia - opportunistic pathogen, used in
  studies of germ warfare
• Yersinia pestis - plague
• Vibrio cholera - cholera
• Haemophilus influenza - major cause of meningitis
  in children

29
Yersinia pestis proliferates inside phagocytic
cells
Plague
Figure 38.9 (a)
30
Plague
Yersinia pestis causative agent
Figure 38.9 (b) and (c)
31
Plague (A Select Agent)

• caused by Yersinia pestis, a gram-negative
  organism
• initial spread by contact with flea-infested
  animals followed by spread among people by
  airborne transmission
• in body multiply in blood and lymph
• survive and proliferate in phagocytic cells

32
Plague

• clinical manifestations
• subcutaneous hemorrhages, fever, and buboes
  (hence name bubonic plague)
• high mortality if untreated
• pneumonic plague arises from
• primary exposure to infectious respiratory
  droplets of infected persons or cats
• secondary to hematogenous spread in a patient
  with bubonic plague

33
Plague

• diagnosis made in reference labs which use direct
  microscopic examination, culture and serological
  tests, and PCR
• treatment, prevention, and control
• antibiotic therapy
• ectoparasite and rodent control, isolation of
  human patients, prophylaxis of exposed persons,
  immunization of persons at high risk

34
Shigellosis

• bacillary dysentery
• caused by four species of genus Shigella
• gram-negative, non-spore forming rods
• organisms cause inflammatory reaction in mucosa
• humans are the only host

35
Shigellosis

• endotoxins and exotoxins may play role in disease
  progression
• watery stools often contain blood, mucus and pus
• diagnosis
• biochemical characteristics
• serology
• treatment, prevention and control
• antibiotic therapy
• prevention by use of good personal hygiene and a
  clean water supply

36
Salmonellosis

• caused by gt2,000 Salmonella serovars,
  gram-negative non-spore forming rods
• transmitted to humans by contaminated foods such
  as beef products, poultry, egg products, and
  water
• disease results from food-borne infection
• bacteria in intestinal mucosa produce enterotoxin
  and cytotoxin

37
Salmonellosis

• symptoms include abdominal, pain, cramps,
  diarrhea, nausea, vomiting and fever
• diagnosis
• isolation of organism from food or patients
  stools
• treatment, control and prevention
• fluid and eletrolyte replacement
• good food handling practices, proper
  refrigeration, adequate cooking

38
Typhoid Fever

• caused by Salmonella enterica subspecies enterica
  serovar Typhi a gram-negative rod
• acquired by ingestion of food or water
  contaminated by feces in infected humans or
  person-to-person contact
• paratyphoid fever
• milder form of disease

39
Typhoid Fever

• bacteria spread from small intestine to lymphoid
  tissue, blood, liver and gallbladder
• symptoms include fever, headache, abdominal pain,
  anorexia and malaise
• in carriers (e.g., Typhoid Mary) bacteria grow in
  gallbladder and reach intestine through bile duct

40
Typhoid Fever

• diagnosis
• demonstration of typhoid bacilli in blood, urine,
  or stools
• serology (Widal test)
• treatment, prevention and control
• antibiotic therapy
• vaccine for high risk individuals
• purification of drinking water, prevention of
  food handling by carriers, and isolation of
  patients

41
ANAEROBIC GRAM NEGATIVE STRAIGHT, CURVED AND
HELICAL RODS 2nd ed. volume 5 phylum
Bacteroidetes

• obligate anaerobes
• straight, curved or helical rods, many are
  pleomorphic
• motile or non motile
• not biochemically very active, can only undergo
  glycolysis - produces 2 ATP
• example
• Bacteroides - common in intestinal tract,
  opportunistic pathogen

42
ANAEROBIC GRAM NEGATIVE COCCI 2nd ed. volume 3
class 1 Clostridia

• similar to Anaerobic Gram Negative Rods, except
  cocci
• example
• Veillonella - capnophilic, cause of gum disease

43
RICKETTSIAS AND CHLAMYDIAS 2nd ed. volume 5
phylum Clamydiae and volume 2 class
Alphaproteobacteria

• most are obligate intracellular parasites
• between a bacteria and virus
• size may be as large as the largest virus

44
RICKETTSIAS

• rods and cocci
• more complex metabolism than chlamydias
• able to synthesize ATP
• lack a complex developmental cycle like
  chlamydias
• most require growth in vivo, some may grow on lab
  media
• many are associated with various arthropods which
  act as vectors
• may also maintain a mutualistic relationship with
  arthropods
• providing factors essential for the growth and
  reproduction
• families Rickettsiaceae, Bartonellaceae and
  Anaplasmataceae
• examples
• Rickettsia rickettsii - Rocky Mountain spotted
  fever

45
Rocky Mountain Spotted Fever

• caused by Rickettsia rickettsii
• transmitted by ticks
• transovarian passage transmission of bacteria
  from generation to generation of ticks through
  their eggs

Figure 38.10
46
Rocky Mountain Spotted Fever

• clinical manifestations
• vasculitis and sudden onset of headache, high
  fever, chills, and skin rash
• can destroy blood vessels in heart, lungs, or
  kidneys, leading to death
• diagnosis
• observation of signs and symptoms, and
  serological tests
• treatment, prevention,and control
• antibiotic therapy and symptomatic/supportive
  therapy
• tick control and avoidance of ticks

47
CHLAMYDIAS

• absolute reliance on host cells for energy -
  cannot produce ATP
• Gram negative cocci
• do not contain n-acetyl muramic acid (NAM) in
  cell wall - no peptidogylcan
• must be grown in vivo

48
Have a characteristic developmental cycle

• an infectious small particle - "elementary body"
  - (electron dense nucleoid) is taken into the
  host cell by phagocytosis
• elementary body is enclosed within a membrane
  bounded vacuole in the cytoplasm of the host cell
• elementary body is reorganized into a
  "reticulate" or "initial body" 2 or 3 times the
  size of the E. body, but less dense nucleoid
• the reticulate body is metabolically active
  producing proteins, enzymes and nucleic acids
• reticulate body is not infectious
• reticulate body undergoes binary fission until
  many are formed
• reticulate bodies are reorganized into elementary
  bodies and liberated form the
• host cell where they can now proceed to infect
  other cells

49
Examples

• Chlamydia psittaci - bird and human pathogen,
  psitticosis - parrot fever
• Chlamydia trachomatis - cause of urethritis, the
  most prevalent sexually transmitted disease today
  trachoma, keratoconjunctivitis, blindness

50
Psittacosis (Ornithosis)

• caused by Chlamydophilia (Chlamydia) psittaci
• enters respiratory tract, transported to and
  reproduces in liver and spleen, and then invades
  lungs
• infectious disease of birds
• transmitted to humans by direct contact with
  infected birds or by inhalation of dried bird
  excreta
• occupational hazard in poultry industry

51
Psittacosis

• clinical manifestations
• inflammation and hemorrhaging of lung tissue and
  pneumonia
• diagnosis
• isolation from blood or sputum, or by serology
• treatment, prevention, and control
• antibiotic therapy
• chemoprophylaxis for pet birds and poultry

52
Inclusion Conjunctivitis

• caused by C. trachomatis serotypes D-K
• spread primarily by sexual contact
• in newborns, acquired during passage through
  infected birth canal
• clinical manifestations
• copious discharge from eye and inflamed, swollen
  conjunctiva
• in newborn, can cause respiratory system
  infections, including pneumonia
• resolves spontaneously

53
Trachoma

• caused by C. trachomatis serotypes A-C
• transmitted by hand-to-hand contact, contact with
  infected soaps and towels, and flies
• the greatest single cause of blindness throughout
  the world

54
Figure 38.22
55
Trachoma

• treatment, prevention, and control
• diagnosis and treatment same as for inclusion
  conjunctivitis
• health education, personal hygiene, and access to
  clean water for washing

56
MYCOPLASMAS 2nd ed. classified in volume 3
class Molicutes

• no cell wall , enclosed in a single lipoprotein
  cell membrane
• facultative or strict anaerobes
• small amount of genetic material - 1/5 to 1/2 the
  normal
• complex nutritional requirements
• limited biosynthetic abilities
• form very small, sometimes microscopic colonies -
  "fried egg colonies"
• different shapes, flexible since no cell wall -
  cocci to filamentous
• can sometimes pass through bacteriological
  filters lt3 micrometers
• many require cholesterol or urea for growth, so
  sometimes associated with the joints or urinary
  tract

57
Figure 23.3
58
Figure 23.4
59
Examples

• Mycoplasma pneumoniae - primary atypical
  pneumonia

60
Mycoplasmal Pneumonia

• caused by Mycoplasma pneumoniae
• produces peroxide, which may be toxic factor
• spread by close contact and/or airborne droplets
• clinical manifestations
• usually mild in infants and more serious in older
  children and young adults
• headache, weakness, low fever, characteristic
  cough, and pneumonia that persists for weeks

61
Mycoplasmal pneumonia

• diagnosis
• rapid immunological tests
• isolation from respiratory secretions ? fried
  egg appearance of organisms on agar
• treatment, prevention, and control
• other bacteria and viruses cannot be detected and
  immunodiagnostic tests
• antibiotic therapy
• no preventive measures

62
VOLUME II - Gram positives other than
actinomycetes

• GRAM POSITIVE COCCI 2nd ed. volume 3 class 3
  Bacilli
• aerobic, microaerophilic, facultative, or
• anaerobic
• motile or nonmotile
• possess cytochromes (function in respiration)
• all undergo aerobic respiration but may also
  obtain energy by fermentation)

63
Figure 23.13
64
Examples

• Staphylococcus aureus - found on the skin and in
  nose
• cause of boils, abcesses, toxic shock syndrome,
  produces heat stable exotoxin

65
Staphylococcal Diseases

• caused by members of genus of Staphylococcus
• gram-positive cocci, occurring singly, in pairs,
  tetrads, or grape-like clusters
• facultative anaerobes and usually catalase
  positive
• normal inhabitants of upper respiratory tract,
  skin, intestines, and vagina
• S. aureus coagulase positive, pathogenic
• S. epidermidis coagulase negative, less
  pathogenic
• many pathogenic strains are slime producers

66
Staphylococcal scalded skin syndrome (SSSS)

• caused by strains of S. aureus that carry a
  plasmid-borne gene for exfoliative toxin
  (exfoliatin)
• epidermis peels off revealing red area underneath
• diagnosis
• isolation/identification of staphylococcus
  involved or use of commercial kits

67
Staphylococcal scalded skin syndrome (SSSS)

• treatment, prevention, and control
• isolation and identification based on catalase
  test, coagulase test, serology, DNA
  fingerprinting, and phage typing
• antibiotic therapy
• many drug-resistant strains
• personal hygiene, food handling, and aseptic
  management of lesions

68
Staphylococcal scalded skin syndrome (SSSS)

• treatment, prevention, and control
• isolation and identification based on catalase
  test, coagulase test, serology, DNA
  fingerprinting, and phage typing
• antibiotic therapy
• many drug-resistant strains
• personal hygiene, food handling, and aseptic
  management of lesions

69
Staphylococcal Food Poisoning

• bacteria produce heat-stable enterotoxins in food
• properly cooking the food will not destroy toxin
  intoxications can result from thoroughly cooked
  foods
• symptoms include abdominal pain, cramps,
  diarrhea, vomiting and nausea

70
Staphylococcal Food Poisoning

• diagnosis
• based on symptoms or laboratory identification of
  bacteria from food
• enterotoxins can be detected in foods by animal
  toxicity tests
• treatment, prevention, and control
• fluid and electrolyte replacement
• avoidance of food contamination, and control of
  personnel involved in food preparation and
  distribution

71

• Streptococcus - divided into Lancefield groups
  based on differences in cell wall polysaccharides
  - Group A, B etc.
• may cause hemolysis of blood - alpha or beta
• alpha - slight hemolysis, green or cloudy
  appearance on blood agar
• beta - complete hemolysis, clear, colorless zone
  around growth on blood agar
• Streptococcus pyogenes - Strept throat, scarlet
  fever, rheumatic fever - now producing a toxin
  similar to toxic shock (TSLS)
• Necretizing Faciitis "Flesh-eating" bacteria

72
Streptococci
Lancefield grouping system based on
polysaccharide and techoic acid antigens in cell
wall or between cell wall and plasma membrane

• nonmotile
• facultative and
• strict anaerobes
• homolactic
• fermentation

73
Figure 23.17
74
Figure 23.18
75
ENDOSPORE FORMING GRAM POSITIVE RODS AND COCCI
2nd ed. volume 3 class 3 Bacilli and class 1
Clostridia

• aerobic, facultative and anaerobic
• mostly rods, few cocci
• many form exoenzymes which hydrolyze proteins or
  complex polysaccharides
• problem in food spoilage - not killed during
  pasteurization

76
Figure 23.6
77
Examples

• Bacillus cereus - cause food poisoning
• Bacillus anthracis - pathogenic to humans and
  animals, tested for germ warfare, usually
  transmitted by animals (sheep and goats) may
  affect the skin, respiratory tract or
  gastrointestinal tract, varied symptoms
• Bacillus thuringiensis - used as a biological
  pesticide

78

• Clostridium botulinum - botulism
• Clostridium tetani - tetanus
• Clostridium perfringens - gas gangrene and food
  poisoning
• Clostridium difficile nosocomial infections,
  post antibiotic infections

79
Figure 23.7
80
Figure 23.9
81
endospore
parasporal body
Figure 23.10 (a)
82
REGULAR NON SPORE FORMING GRAM POSITIVE RODS
2nd ed. volume 3 class 3 Bacilli

• aerobic, facultative or anaerobic
• short or long rods, regular shape

83
Examples

• Listeria monocytogenes - cause of the Jalisco
  cheese food poisoning, the worst epidemic in the
  U.S. - many other outbreaks also problem in raw
  milk and vegetables, grows at refrigeration
  temps, hidden in the cow's white blood cells in
  milk and may survive pasteurization, high
  fatality, affects pregnant women, meningitis,
  gastrointestinal symptoms
• Lactobacillus acidophilus - normal flora of
  intestinal and urogenital tract, used in the
  production of cheese and yogurt

84
Figure 23.14
85
IRREGULAR NON SPORE FORMING GRAM POSITIVE RODS
2nd ed. volume 4 phylum Actinobacteria

• pleomorphic, irregularly shaped rods or branching
  filaments
• aerobic, facultative or anaerobic

86
Examples

• Mycobacterium tuberculosis - tuberculosis
• Mycobacterium leprae - leprosy (Hansen's disease)
• Mycobacterium smegmatis - "smegma" found in the
  genitals

87
Figure 24.10
88
VOLUME III - Gram negatives with distinctive
properties, cyanobacteria and archaeobacteria
89
OXYGENIC PHOTOTROPHIC BACTERIA CYANOBACTERIA
2nd ed. volume 1 phylum Cyanobacteria

• produce oxygen during photosynthesis

90
Figure 21.11
91
Oxygenic Photosynthetic Bacteria
Figure 21.8
92
ANOXYGENIC PHOTOTROPHIC BACTERIA- 2nd ed. volume
2 class 1 Alphaproteobacteria and volume 1 phylum
Chlorobi

• Gram negative
• anaerobic
• photolithotrophic and photoorganotrophic
  metabolism
• use light as energy and organic and inorganic
  sources for electrons
• contain bacteriochlorophyll and carotenoid
  pigments
• primitive

93

• do not liberate oxygen during photosynthesis
• absorb long wavelengths of light, the reds and
  infrareds
• found in anaerobic fresh or marine water such as
  stagnant ponds, salt marshes
• can be very deep, where the red and infrared
  light make their way to those depths
• the shorter light is absorbed by the oxygenic
  organisms
• some nitrogen fixation
• color is determined by the carotenoid pigments
  and divides them into 2 groups

94
Purple

• bacteriochlorophyll a and b found in the cell
  membrane and mesosomes
• diversity of shapes
• may divide by binary fission or budding
• may be sulfur - photoautotrophs and anaerobic
• or nonsulfur - photoheterotrophs and
  aerotolerant
• example
• Rhodospirillum

95
Figure 22.3
96
Green

• bacteriochlorophyll c and d, sometimes a
• smaller group than the purple
• may be sulfur or nonsulfur
• example
• Chlorobium

97
BUDDING AND/OR APPENDAGED BACTERIA 2nd ed.
volume 2 class 1 Alphaproteobacteria

• Gram negative
• aerobic, microaerophilic or facultative
• varied morphology
• form prothecae - extensions of the cell wall and
  plasma membrane that help them attach to surfaces
• may form stalks - nonliving ribbon-like
  appendages that are excreted by the cell
• reproduce by budding - at the end of the
  prothecae
• daughter cell may possess a flagellum - now call
  a swarm cell
• secrete an adhesive material "holdfast"
• cells become attached to each other, may form a
  "rosette"
• may also bud directly from the mother cell

98
Figure 22.5
99
Caulobacter
Figure 22.7 (b) and (c)
100
Caulobacter
Figure 22.7 (d)
101
SHEATHED BACTERIA 2nd ed. volume 2 class 2
Betaproteobacteria

• Gram negative
• rods which are covered by a sheath to form
  chains, may also form branches
• only "pseudo branches" because just held together
  by the sheath
• aerobic
• may have a holdfast cell to attach to surfaces
• sheath offers some protection
• sheath can be surrounded by a slime layer
• may also become encrusted with iron and manganese
• may form conidia in unfavorable environments
  offering some protection
• found in fresh or marine waters

102
FRUITING GLIDING BACTERIA THE MYXOBACTERIA
2nd ed. volume 2 class 4 Deltaproteobacteria

• Gram negative
• short rods
• strict aerobes
• may develop pigments
• non motile but exhibit gliding or creeping
  motility on solid surfaces leaving a "slime
  track" (like a snail)
• in low nutrient environment the cells swarm
  together and form fruiting bodies
• fruiting bodies contain myxospores - a type of
  spore which is resistant to UV light and
  desiccation but not to heat
• fruiting bodies can be simple or complex, either
  a mass held together by slime or on a stalk of
  slime with the myxospores enclosed in a sac
• found in soil and dung

103
Figure 22.36
104
Figure 22.37
105
Example

• Myxobacteria - myxo "slime"

106
NON-FRUITING GLIDING BACTERIA 2nd ed. volume 5
phylum Bacteriodetes

• gliding as above
• Gram negative
• aerobic or microaerophilic
• rods or filamentous
• example
• Capnocytophaga - found in oral cavity, between
  enamel and gum may be a cause of periodontal
  disease

107
Nonphotosynthetic, Nonfruiting Gliding Bacteria
Figure 21.18
108
ARCHAEOBACTERIA 2nd ed. volume 1 Domain Archaea

• not Eubacteria - different phylogenetic origins
• peptidoglycan does not contain NAM
• lipids in the cytoplasmic membrane are different
• some differences in protein synthesis

109
Three Major Groups

• Methanogenic
• grow in anaerobic conditions such as stagnant
  ponds
• sewage sludge and volcanic areas
• metabolic byproduct is methane
• responsible for producing "swamp or marsh gas"

110
Selected Methanogens
Figure 20.9
111

• Extremely halophilic
• require high salt concentrations
• found in the Dead Sea, Great Salt Lake and other
  similar areas
• able to photosynthesize but utilize rhodopsin, a
  pigment similar to the visual pigment in

112
Examples of Halobacteria
Figure 20.12
113

• Extremely Thermoacidophilic
• grow in hot acidic environments,
• hot springs, gt 90 C

114

• grow in geothermally heated water or soils that
  contain elemental sulfur

Figure 20.5 (a)
115
VOLUME IV Actinomycetes
116
NOCARDIOFORMS AND ACTINOMYCETES 2nd ed. volume
4 phylum Actinobacteria

• may be acid fast and contain mycolic acid
• filamentous and branching filaments
• form a substrate mycelium - sometimes aerial
• mycelium that can give rise to conidia
• example
• Nocardia - normally a saprophyte but can be
  opportunistic (on the rise)

117
Nocardia
Figure 24.12
118
aerial hyphae
substrate mycelium
Figure 24.2
119
Figure 24.3
120
Figure 24.6
121
STREPTOMYCES AND RELATED GENERA 2nd ed. volume
4 phylum Actinobacteria

• rods or pleomorphic rods
• filamentous with or without branching
• usually Gram positive
• aerobic, facultative or anaerobic
• may form mycelium
• example
• Streptomyces - produce many antibiotics,
  streptomycin, tetracycline, chloramphenicol,
  erythromycin and others

122
Figure 24.15
123
Figure 24.18 (a) and (b)