Chapter II Eukarya,
Eukaryotic Microorganisms
? Algae,Phototrophic eukaryotic microorganisms
? Fungi,Nonphotosynthetic eukaryotic
microorganisms that contain rigid cell walls
? Slime molds,nonphototrophic eukaryotic
microorganisms that lack cell walls and that
aggregate to form fruiting structures (cellular slime
molds) or masses of protoplasm (acellular slime
molds)
? Protozoa,unicellular eukaryotic microorganisms
that lack cell walls
Seveal concepts
? Mycologists,scientists who study fungi
? Mycology,the scientific discipline dealing
with fungi.
? Mycotoxixology,the study of fungal toxins
and their effects.
? Mycosis/mycoses,the diseases caused by
fungi in animals.
Importance of fungi
? 1,decomposers
? 2,Major cause of plant diseases
? 3,Many diseases of animals and humans are caused by
fungi
? 4,products,the making of bread,wine,beer(yeasts);
the preparation of some cheeses,soy sause and sufu; the
commercial production
of many organic acids and certain drugs; The
manufacture of many antibiotics and
immunosuppressive drug cyclosporine.
? 5,Important research tools in the study of fundamental
biological processes.
Fungi,Molds,Yeasts and Mushrooms
? Habitats diverse,aquatic in fresh water or marine,
terrestrial in soil or on dead plant,a few are human
parasitic
? Have rigid cell walls (resemble plant cell walls
architecturally,not chemically) containing chitin (some
with mannans,galactosans,chitosans instead of chitin)
? Fungal cell walls are 80-90% polysaccharide,with
proteins,lipids,polyphosphates and inorganic ions
making up the wall-cementing matrix
Thallus, the body or vegetative structure of a fungus.
? Hypha (hyphae),long,branched,threadlike filament
? Mycelium,a tangled mass or tissurlike aggregation
? Coenocytic,hyphae that protoplasm streams
through hyphae,uninterrupted by cross walls.
? Septate,the hyphae have cross walls called septa
with either a single pore or multiple pores that
permit cytoplasmic streaming,(Septa,cross walls
with either a single pore or multiple pores that
permit cytoplasmic streaming.)
YM shift
? Many fungi that cause diseases in humans and
animals,are dimorphic,they have two forms.
? 1,The yeast (Y) form in the animals
? 2,The mold or mycelial form (M) in the external
enviroment.
? Plant-associated fungi,the mycelial form in the
plantl the yeast form in the external enviroment.
yeasts
? Unicellular fungus,spherical to egg
shaped,single nucleus and
repriduces either asexually by
budding and transverse division or
sexually throough spore formation
? No flagella,possess most of the other
eucaryotic organelles..
Yeasts,unicellular fungi (ascomycetes)
? Division,budding
? Do not form filaments
? Some form filaments
? Some can mate.
Cillia and flagella
? Both are associated whth motility.
? Both are whiplike and beat to move the
microorganism along
? Difference,1.cilia are typically only 5 to 20 m
inlength,whereas flagella are 100 to 200 m long.
2,Distinctive movement patterns:
flagella,move in an undulating fashion and
generate planar or helical waves orignating at
either the base or the tip.
cillia:like an oar or
Cilia and flagella structure
? Fig4.24p90
Colony
Eucaryotic cell structure
The Nucleus
The nucleus is both
a storehouse and a
processing factory
for genetic
information.
The process of
protein synthesis
occurs in the
cytoplasm
Chromosomes and DNA
Histones are spaced
along the DNA double
helix at regular intervals,
the DNA itself being
wound around each
histone molecule,The
packing forms a discrete
structure called a
nucleosome,Nucleosomes
aggregate and form a
fibrous material called
chromatin,Chromatin
itself can be compacted by
folding and looping to
eventually form an intact
chromosome
Mitosis (有丝分裂 )
? During cell division,the nucleus
divides following a doubling of
the chromosome number,a
process called mitosis,yielding
two cells,each with a full
complement of chromosome.
? Metaphase,chromosomes are
paired in the center of the cell.
? Anaphase,chromosomes are
separating.
Organelles,Mitochondria and Chloroplasts
? Eukaryotic cells have a number of important functions
localized in discrete bodies called organelles:
? Mitochondria,in which energy metabolism is carried
out,
? Chloroplasts:in which the process of photosynthesis is carried out in plants and algae.
Structure of the mitochondrion
A bilayer of phospho-
lipid with embedded
proteins.
Cristae(脊 ),sites of
enzymes involved in
respiration and ATP
production and of
specific transport
proteins that regulate
the passage of
metabolites into and
out of the matrix of the
mitochondrion.
Matrix(基质 ),contains a
number of enzymes involved
in the oxidation of organic
compounds (TCA cycle).
Structure of the chloroplasts
? Thylakoids(类囊体 ):the thylakoid
membrane is highly impermeable to
ions and other metabolites because its
function is to establish the proton
motive force necessary for ATP
synthesis.
Detailed structure of the chloroplasts
Stroma contains large amounts of the enzyme ribulose bisphosphate
carboxylase (RubisCO) that convert CO2 to organic form.
Relationships of organelles to bacteria
? It was suggested that
mitochondria and
chloroplasts are
descendents of ancient
prokaryotic organisms.
? Endosymbiosis theory:
Eukaryotes arose from
the engulfment of a
prokaryotic cell by a
large cell.
? Evidences:
? Mitochondria and
chloroplasts contain
DNA,
? Mitochondria and
chloroplasts contain
their own ribosomes
? Antibiotic specificity
? Phylogeny
Asexual spores
? Arthroconidia,by the separation of hyphae through
splitting of the cell wall or septum to form cells that behave
as spores.
? Chlamydospores,the cells are surrounded by a thick wall
before separation.
? Sporangiospores,the spores develop within a sporangium
(sac) at a hyphal tip.
? Conidiospores,the spores are not enclosed in a sac but
produced at the tips or sides of the hypha.
? Blastospores,spores produced from a vegetative mother
cell by budding.
Molds,filamentous fungi
? Conidia,asexual spores,pigmented,resistant to
drying
Comparison of procaryotic and
eukaryotic cells
Table
3-5
p62
Questions
? What are Eukaryotic Microorganisms
? Several concept
? Importance of fungi
? YM shift
? The character and reproduction of yeast
? Special style of mycelium
? Cillia and flagella
? The feature of colony
? Eucaryotic cell structure
? The reproduction of fungi
? Comparison of procaryotic and eukaryotic cells
Classification of Fungi
? Based on
–morphological properties
–sexual life cycles
子囊菌
担子菌
接合菌
卵菌
半知菌
多核的
Eukaryotic Microorganisms
? Algae,Phototrophic eukaryotic microorganisms
? Fungi,Nonphotosynthetic eukaryotic
microorganisms that contain rigid cell walls
? Slime molds,nonphototrophic eukaryotic
microorganisms that lack cell walls and that
aggregate to form fruiting structures (cellular slime
molds) or masses of protoplasm (acellular slime
molds)
? Protozoa,unicellular eukaryotic microorganisms
that lack cell walls
Seveal concepts
? Mycologists,scientists who study fungi
? Mycology,the scientific discipline dealing
with fungi.
? Mycotoxixology,the study of fungal toxins
and their effects.
? Mycosis/mycoses,the diseases caused by
fungi in animals.
Importance of fungi
? 1,decomposers
? 2,Major cause of plant diseases
? 3,Many diseases of animals and humans are caused by
fungi
? 4,products,the making of bread,wine,beer(yeasts);
the preparation of some cheeses,soy sause and sufu; the
commercial production
of many organic acids and certain drugs; The
manufacture of many antibiotics and
immunosuppressive drug cyclosporine.
? 5,Important research tools in the study of fundamental
biological processes.
Fungi,Molds,Yeasts and Mushrooms
? Habitats diverse,aquatic in fresh water or marine,
terrestrial in soil or on dead plant,a few are human
parasitic
? Have rigid cell walls (resemble plant cell walls
architecturally,not chemically) containing chitin (some
with mannans,galactosans,chitosans instead of chitin)
? Fungal cell walls are 80-90% polysaccharide,with
proteins,lipids,polyphosphates and inorganic ions
making up the wall-cementing matrix
Thallus, the body or vegetative structure of a fungus.
? Hypha (hyphae),long,branched,threadlike filament
? Mycelium,a tangled mass or tissurlike aggregation
? Coenocytic,hyphae that protoplasm streams
through hyphae,uninterrupted by cross walls.
? Septate,the hyphae have cross walls called septa
with either a single pore or multiple pores that
permit cytoplasmic streaming,(Septa,cross walls
with either a single pore or multiple pores that
permit cytoplasmic streaming.)
YM shift
? Many fungi that cause diseases in humans and
animals,are dimorphic,they have two forms.
? 1,The yeast (Y) form in the animals
? 2,The mold or mycelial form (M) in the external
enviroment.
? Plant-associated fungi,the mycelial form in the
plantl the yeast form in the external enviroment.
yeasts
? Unicellular fungus,spherical to egg
shaped,single nucleus and
repriduces either asexually by
budding and transverse division or
sexually throough spore formation
? No flagella,possess most of the other
eucaryotic organelles..
Yeasts,unicellular fungi (ascomycetes)
? Division,budding
? Do not form filaments
? Some form filaments
? Some can mate.
Cillia and flagella
? Both are associated whth motility.
? Both are whiplike and beat to move the
microorganism along
? Difference,1.cilia are typically only 5 to 20 m
inlength,whereas flagella are 100 to 200 m long.
2,Distinctive movement patterns:
flagella,move in an undulating fashion and
generate planar or helical waves orignating at
either the base or the tip.
cillia:like an oar or
Cilia and flagella structure
? Fig4.24p90
Colony
Eucaryotic cell structure
The Nucleus
The nucleus is both
a storehouse and a
processing factory
for genetic
information.
The process of
protein synthesis
occurs in the
cytoplasm
Chromosomes and DNA
Histones are spaced
along the DNA double
helix at regular intervals,
the DNA itself being
wound around each
histone molecule,The
packing forms a discrete
structure called a
nucleosome,Nucleosomes
aggregate and form a
fibrous material called
chromatin,Chromatin
itself can be compacted by
folding and looping to
eventually form an intact
chromosome
Mitosis (有丝分裂 )
? During cell division,the nucleus
divides following a doubling of
the chromosome number,a
process called mitosis,yielding
two cells,each with a full
complement of chromosome.
? Metaphase,chromosomes are
paired in the center of the cell.
? Anaphase,chromosomes are
separating.
Organelles,Mitochondria and Chloroplasts
? Eukaryotic cells have a number of important functions
localized in discrete bodies called organelles:
? Mitochondria,in which energy metabolism is carried
out,
? Chloroplasts:in which the process of photosynthesis is carried out in plants and algae.
Structure of the mitochondrion
A bilayer of phospho-
lipid with embedded
proteins.
Cristae(脊 ),sites of
enzymes involved in
respiration and ATP
production and of
specific transport
proteins that regulate
the passage of
metabolites into and
out of the matrix of the
mitochondrion.
Matrix(基质 ),contains a
number of enzymes involved
in the oxidation of organic
compounds (TCA cycle).
Structure of the chloroplasts
? Thylakoids(类囊体 ):the thylakoid
membrane is highly impermeable to
ions and other metabolites because its
function is to establish the proton
motive force necessary for ATP
synthesis.
Detailed structure of the chloroplasts
Stroma contains large amounts of the enzyme ribulose bisphosphate
carboxylase (RubisCO) that convert CO2 to organic form.
Relationships of organelles to bacteria
? It was suggested that
mitochondria and
chloroplasts are
descendents of ancient
prokaryotic organisms.
? Endosymbiosis theory:
Eukaryotes arose from
the engulfment of a
prokaryotic cell by a
large cell.
? Evidences:
? Mitochondria and
chloroplasts contain
DNA,
? Mitochondria and
chloroplasts contain
their own ribosomes
? Antibiotic specificity
? Phylogeny
Asexual spores
? Arthroconidia,by the separation of hyphae through
splitting of the cell wall or septum to form cells that behave
as spores.
? Chlamydospores,the cells are surrounded by a thick wall
before separation.
? Sporangiospores,the spores develop within a sporangium
(sac) at a hyphal tip.
? Conidiospores,the spores are not enclosed in a sac but
produced at the tips or sides of the hypha.
? Blastospores,spores produced from a vegetative mother
cell by budding.
Molds,filamentous fungi
? Conidia,asexual spores,pigmented,resistant to
drying
Comparison of procaryotic and
eukaryotic cells
Table
3-5
p62
Questions
? What are Eukaryotic Microorganisms
? Several concept
? Importance of fungi
? YM shift
? The character and reproduction of yeast
? Special style of mycelium
? Cillia and flagella
? The feature of colony
? Eucaryotic cell structure
? The reproduction of fungi
? Comparison of procaryotic and eukaryotic cells
Classification of Fungi
? Based on
–morphological properties
–sexual life cycles
子囊菌
担子菌
接合菌
卵菌
半知菌
多核的
