Characteristics Prokaryote Eukaryote (Fungi)

1. Nucleus - +

2. Cell wall peptidoglikan, proteinmurein

lipid bilayer, glukan, cellulose, khitin,

3. Cytoplasm lack membran boundorganel, mesosom

ribosome (70 S)

contain many membran boundorganel, i.e. mitochondrion, ER,lysosome, Golgi apparatus,vacuole, vesicle, SPB, cystoskleton,

ribosome (80 S) with large subunits(28S, 5.8 S and 5.8 S) + small unit(18 S)

4. DNA circular, simple linear with protein histone, morecomplex

5. Size 1-10 um 10 times larger (10-100 um)

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FUNGAL PHYSIOLOGY

1. Cell architecture and hyphal growth

2. Spore: dormancy, activation and germination

3. Host-Parasite Interaction

MICROBIAL EUCARYOTIC CELL ARCHITECTURE

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Prokaryotic cell

Eukaryotic cell

NUCLEUSOrganization of DNA in chromosome1. Number of DNA molecules = number of chromosom2. Chromatin : DNA + protein (basic histon + acidic protein) + small

amount of RNAFungus

Aspergillus nidulans

Cochliobolus heterosporus

Magnaporthe grisea

Neurospora crassa

Saccharomyces cerevisiae

Filobasidiella neoformans

Tilletia caries

Ustilago maydis

Acremonium chrysogenum

Fusarium oxysporum

Phoma tracheiphila

Number of molecule

8

15

6-10

7

16

11

12-25

20

8

8

12

Estimated size (Mbp)

2.9-5

1,3-3,7

5-12

4-12

0.7-2.2

0.4-1

0.88-4

0.3 - <2

1,7-4

2,2=6,2

0.7-1.6

3. Protein histone (H1, H2A, H2B, H3 and H4)- except H1, other protein histones organised into nucleosome- the presence of H1 implies a difference in the structure of

chromatin fibrils.- H1 lack in S. cerevisiae, S. pombe, Achlya

4. Nucleosome:- presence very 154-185 bp DNA, with core DNA 140 bp

- connected by DNA strands 40-60 bp that complexed with H1fiber- organised DNA into 10 nm thick fiber, and further to 30 nm

dpend on the presence of H1.

5. Centromere and Telomere- essential for replication and segregation- centromere composed of repetitive DNA sequence- telomere, ends of choromosome, multiple C rich sequence at

5’end and G-rich sequence at 3’end.- telomere is dynamic, changing length under various condition

- Telomere essential for complete replication, otherwise thechromosome have broken end and this may fuse withother broken end chromosom or may be degraded byendonuclease.

6. Nucleolus- associated with chromosomal region : NOR (nucleolar

organizer region)- NOR contain rDNA repeats and is the site of

transcription, processing and assembly preribosomes- Nucleolar structure depends on the presence of active

RNA polymerase 1 and DNA topoisomerase

7. Nuclear division

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NUCLEUS: Nuclear and Cell Division Cycle

Sexual reproduction

Growth ceased

Cell division:1) Cell wall growth ( bud emergence and growth, cell wall elongation

and septal formation)2) Cytoplasmic event (especially SPB formation)3) DNA synthesis

nuclearcycle

4) Division process may be centric (Protoctists Fungi, Oomycetes andChytridiomycetes) or non-centric (other Eufungi).

5) Centric: having centriole and electron-opaque material at the poles ofspindle (SPB)Non-centric, lack centriole

6) Nucleolus and nuclear envelope persist during mitosis

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5

NUCLEUS BEHAVIOUR DURING CELL DIVISION

sentriol

selubungnukleus

RIBOSOME1. Small particle in the cytosol and mtochondria2. Site of protein synthesis3. Composed of RNA and protein : 41-53% RNA and 47-59%

protein (cytosolic)4. Cytosolic ribosome: free or bounded to nuclear membrane or ER,

four kinds of RNA 18 S, 25S, 5S and 5.8 S5. Mitochondrial ribosom: located between cisternae6. Composed of 2 subunits (60S and 40S).

Large subunit : 25S, 5S and 5.8 S RNA with 37-45 kinds ofprotein. Small subunit : 18S RNA with 21-35 kinds of protein

7. Presence as single ribosome (monosome) or as aggregates(polysome)

8. rRNA are produced in the nucleolus from rDNA

Fungus Base composition(G+C)

Molecular Size (S)

Cytosol Mitochondria Cytosol Mitochondria

Aspergillus 51 31 26, 17 23, 15

Trichoderma 49.5 34 26, 17 22, NR

Neurospora 50 35 26, 17 23, 16

Saccharomyces 47.5 26 26, 17 22, 14

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Mitochondria1. Double membraned organelles with smooth outer membrane and

convolvulated inner membrane (plate like or tubular cristae) Highlyvariable organelles, change in form, chemical composition andfunctional abilities depending on their location, developmentalstages of the fungus and growth condition

2. Circular to oval or elongated. Circular mitochondria in hyphal tips,elongated in older hyphae

3. Mitochondrial DNA (mt DNA): located in the fibrous region of thematrix, coded for rRNA and tRNA in the mitochondria

4. Mitochondrial protein coded by nuclear gene and syntesized incytosolic ribosom and imported in.

5. Mitochondrial ribosome sensitive to chloramphenicol, insensitive tocycloheximide

Comparison between cytosolic and mitochondrial ribosome

Fungus Growth rate(ug/h)

Length of G1phase (min)

Length of S+G2phase (min)

Saccharomycescerevisiae

0.10 173 227

0.23 63 117

0.52 13 67

Schizocharomycespombe

0.038 860 250

0.67 370 250

0.10 140 260

0.22 0 240

Neurospora crassa 0.18 106 86

0.42 22 70

0.58 7 57

Element Schizophyllum commune

%

Lagenidium giganteum

%

Glukan 60.8 77

Cellulosa 0 9.1

Chitin 12.5 0

Manose 3.4 4.0

Glucose 6.8 0

Amino acid and protein 7.2 5.8

Lipid 3.0 2.5

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The relationship between nuclear cycle timing and specific growth rate

CELL WALL

Composition of hyphal cell wall

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Neurospora crassa

(a) Outer layer: glucan amorphous 1-3 dan 1-6(b) Glycoprotein layer(c) Protein

(d) Chitin microfibril attach to protein(e) plasmalema

mucous

Soluble glucan in KOH

Chitin fibril in 1-3 glucanmatrix

plasmalema

Cell wall of Agaricus brunescens

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Chemical Differentiation of the wall of Mucor rouxii

Dry weight (% of total)Component Yeasts Hyphae Sporangiospores Spores

ChitinChitosanMannoseFucoseGalactoneGlucuronic acidGlucoseProteinLipidPhosphateMelanin

828931120106220

93324212068230

1821121250.19510

2105022431610310

Fungus Compound dry weight (%)Lipid Protein carbohydrate Nucleic acid

S. cerevisiaeN. CrassaC. tropicalisB. DermatitidisC. albicans mycelium

yeast

392923174552

495660503143

514183125

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72-20.50.3

PlasmalemmaLipid bilayer3 layers : lipid bilayer interspersed with protein and glycoprotein forming a fluid mosaic.Enzyme: chitin synthetase and H+-ATPase

Proximal composistion of fungal plasmalemma

LOCUS AND DEVELOPMENT OF THALLUS1. Locus of hyphal extension: tip of a hypha

mitochondriaCell wall

vesikel

ribosomemicrotubuleGolgi

complexspitzenkorper

10 um, actively growth site(undifferentiated hypha)through plastic deformation

Growth detection: usingantibodies, amrking thepreexisting wall

plasticize

Hydrolitic enzyme:cellulase, gluncanase

Lomasome

of cell wall

2. Development of thallus: apical dominance1. Primary hyphal tip grow faster than the branching. Elongation of hyphae from spores

increased with time until a maximum rate achieved. Germ tube in maximum growthrate, branching begin and linear growth rate stable

2. Apical dominance was affected bya. Temperatureb. Nutrition. Declining was caused by nutrition limitation

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When nutrition is unlimited, hyphae growat a constant level

A single cell grow and reachmaximum level, bud formed andgrowth with a similar pattern

GROWTH MEASUREMENTChoosing method:1. Purpose2. Ambiguities of interpretation3. Practicallity of application

GROWTH RATES OF COLONIES (batch culture)

REGULATION OF GROWTH

Phase :1. Lag2. Exponential3. Declining4. Stationary5. death

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12

Countinous culture

Temperature

PHYSICAL FACTORS AFFECTING GROWTH

Fungi:•thermophile• mesophile•psychrophile

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Temperature

Water availability