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2 The "six" kingdom taxonomic scheme

What do you think about………….. T B C

Prokaryotes are classified into two groups :

Founded by Anthony van Leeuwenhoek (1674).Anthony van Leeuwenhoek1674 bacterium named by Ehrenberg (1828), from Yunani word is βακτηριον meaning "small stick".

6 E. coli on the surface of the intestine.

7 E. coli on the surface of human skin

Kingdom Archaebacteria Found in harsh environments (undersea volcanic vents, acidic hot springs, salty water) Cell walls without peptidoglycan Plasma membrane contain lipid with eter bound Ribosom contain some RNA Polymerase Subdivided into 3 groups based on their habitat methanogens, 2. thermoacidophiles, & 3. extreme halophiles

Archaea live in anaerobic swamps salt lakes acidic hot springs deep-sea hydrothermal vents animal digestive systems

Kingdom Eubacteria (true bacteria) Cell walls with peptidoglycan Ribosom contain one kind of RNA Polymerase Plasma membrane contain lipid with ester bound Most bacteria in this kingdom Come in 3 basic shapes --- cocci (spheres), bacilli (rod shaped), spirilla (corkscrew shape)

THE STRUCTURE

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Structure of bacteria

Cell Wallprotects the cell and gives shape Outer Membrane protects the cell against some antibiotics (only present in Gram negative cells) Cell Membrane regulates movement of materials into and out of the cell; contains enzymes important to cellular respiration Cytoplasm contains DNA, ribosomes, and organic compounds required to carry out life processes Chromosome carries genetic information inherited from past generations Plasmid contains some genes obtain through genetic recombination Capsule, and slime layer protects the cell and assist in attaching the cell to other surfaces

STRUCTURE FUNCTION the cell Pilus (Pili) assist the cell in attaching to other surfaces, which is important for genetic recombination Flagellummoves the cell Mesosom To form of cell membrane when cleavage begin To help the sparatition chromosome duplicasted Endosporeprotects the cell against harsh environmental conditions, such as heat or drought

Pili help cells attach to surfaces Figure 16.12B Pili

Figure 16.12C Endospore Endospores allow certain bacteria to survive environmental extremes in a resting stage

Spheres (cocci) are the most common Rods (bacilli) variety of shapes Figure 16.9A-C Curves or spirals

Kokus (Coccus) dalah bakteri yang berbentuk bulat seperti bola, dan mempunyai beberapa variasi sebagai berikut: Mikrococcus, jika kecil dan tunggal Diplococcus, jka bergandanya dua-dua Tetracoccus, jika bergandengan empat dan membentuk bujursangkar Sarcina, jika bergerombol membentuk kubus Staphylococcus, jika bergerombol Streptococcus, jika bergandengan membentuk rantai

Basil (Bacillus) adalah kelompok bakteri yang berbentuk batang atau silinder, dan mempunyai variasi sebagai berikut: Diplobacillus, jika bergandengan dua-dua Streptobacillus, jika bergandengan membentuk rantai Spiril (Spirilum) adalah bakteri yang berbentuk lengkung dan mempunyai variasi sebagai berikut: Vibrio, (bentuk koma), jika lengkung kurang dari setengah lingkaran Spiral, jika lengkung lebih dari setengah lingkaran

Diplobasil Streptococcus

23 Campylobacter jejuni, curved (vibrio-shaped), rod

BASED ON THE MOVEMENT ORGANS MONOTRICAMFITRICLOFOTRICPERITRIC WHEN THE BACTERIA DON’T HAVE FLAGEL IS CALLED ATRIC

Berdasarkan kisaran suhu aktivitasnya, bakteri dibagi menjadi 3 golongan: Bakteri psikrofil, yaitu bakteri yang hidup pada daerah suhu antara 0°– 30°C, dengan suhu optimum 15°C. Bakteri mesofil, yaitu bakteri yang hidup di daerah suhu antara 15° – 55°C, dengan suhu optimum 25° – 40°C. Bakteri termofil, yaitu bakteri yang dapat hidup di daerah suhu tinggi antara 40° – 75°C, dengan suhu optimum °C

Bacterial Reproduction & Genetic Recombination Most bacteria reproduce asexually by binary fission (chromosome replicates & then the cell divides) Bacteria replicate (double in number) every 20 minutes under ideal conditions Bacteria contain much less DNA than eukaryotes Bacterial plasmids are used in genetic engineering to carry new genes into other organisms Bacteria recombine genetic material in 3 ways transformation, conjugation, transduction

Conjugation Sexual reproductive method Two bacteria form a conjugation bridge or tube between them Pili hold the bacteria together DNA is transferred from one bacteria to the other

Transformation Bacteria pick up pieces of DNA from other dead bacterial cells New bacterium is genetically different from original

Transduction

Staining properties of bacteria by Danish microbiologist, Hans Gram Purple with Crystal Violet & iodine ; rinsed with alcohol to decolorize; then restained with Safranin Then bacteria which become violet are called gram positive and remaining colourless bacteria called gram negative.

Materi Pelatihan Guru32 REACTION OF CELL TO STAINING GRAM

Materi Pelatihan Guru33

Compare gram + and gram -

Gram-positive bacteria (Gram +) Thick layer of peptidoglycan (protein- sugar) complex in cell walls & single layer of lipids Stain purple

Gram-negative bacteria (Gram -) Cell walls have a thin layer of peptidoglycan & an extra layer of lipids on the outside Stain pink or reddish Lipid layer prevents the purple stain & antibiotics from entering (antibiotic resistant

Methods of Respiration Obligate aerobic bacteria Obligate anaerobes Facultative anaerobes Anaerobes carry on fermentation, while aerobes carry on cellular respiration

Methods of Nutrition Saprobes feed on dead organic matter Symbionts make mutually beneficial association with other organisms. Example Rhizobium in root nodules of legume plants Parasites feed on a host cell Photoautotrophs use sunlight for energy, but get carbon from organic compounds (not CO2) to make their own food Chemoautotrophs obtain food by oxidizing inorganic substances like sulfur, instead of using sunlight

THE ROLE