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داﻧﺸﮕﺎه ﻋﻠﻮم ﭘﺰﺷﮑﯽ ﮔﯿﻼن داﻧﺸﮑﺪه ﭘﯿﺮاﭘﺰﺷﮑﯽ ﻣﯿﮑﺮوب ﺷﻨﺎﺳﯽ ﮐﺎرﺷﺘﺎﺳﯽ ﻋﻠﻮم آزﻣﺎﯾﺸﮕﺎﻫﯽ ﺳﺎﺧﺘﻤﺎن ﺑﺎﮐﺘﺮﯾﻬﺎ دﮐﺘﺮ اﯾﺮج ﻧﯿﮑﻮﮐﺎر اﺳﺘﺎد رﺷﺘﻪ ﻣﯿﮑﺮوب ﺷﻨﺎﺳﯽ ﺑﺎﻟﯿﻨﯽ SIZES, SHAPES, AND ARRANGEMENTS OF BACTERIA micrometers (µm) Most bacteria come in one of three basic shapes: 1)coccus 2) rod or bacillus 3) spiral 1. The coccus The cocci are spherical or oval bacteria having one of several arrangements based on their planes of division. a. Division in one plane produces : diplococcus : pair of cocci streptococcus :chain of cocci b. Division in two planes produces a tetrad :square of 4 cocci c. Division in three planes produces a sarcina : cube of 8 cocci d. Division in random planes produces a staphylococcus:cocci in irregular, often grape-like clusters An average coccus is about 0.5-1.0 (µm) in diameter 2)The rod or bacillus Bacilli are rod-shaped bacteria. Bacilli all divide in one plane a. bacillus: a single bacillus b. streptobacillus: a chain of bacilli c. a coccobacillus: oval and similar to a coccus d. vibrio: curved or comma-shaped rod An average bacillus is 0.5-1.0 µm wide by 1.0-4.0 µm long. 3. The spiral a.Spirillum: thick, rigid spiral ,regular b.Borrellia: thick, rigid spiral ,irregular c.Treponema:thin, flexible spiral d.Leptospira:thin, flexible spiral Spirals range in size from 1 µm to over 100 µm in length PROKARYOTIC CELL STRUCTURE A typical bacterium usually consists of: 1) Cytoplasmic membrane surrounded by a peptidoglycan cell wall and maybe an outer membrane; 2) Fluid cytoplasm containing a nuclear region (nucleoid) and numerous ribosomes; and 3)Often various external structures like a glycocalyx, flagella, and pili. STRUCTURES LOCATED OUTSIDE THE CELL WALL 1) Flagella It is composed of the protein: flagellin A bacterial flagellum has 3 basic parts: A) filament, B) hook, C) basal body : Rings ,Rod Function: 1) Motility 2) Antigenic Structure درﺑﺎﮐﺘﺮﯾﻬﺎي ﮔﺮم ﻣﻨﻔﯽ 4ﺣﻠﻘﻪ در ﺑﺎﮐﺘﺮي ﻫﺎي ﻣﺜﺒﺖ 2ﺣﻠﻘﻪ وﺟﻮد دارد Flagellar arrangements 1) Monotrichous: a single flagellum, usually at one pole 2) Amphitrichous: a single flagellum at both ends of the organism 3) Lophotrichous: two or more flagella at one or both poles 4) Peritrichous: flagella over the entire surface ﻣﮑﺎﻧﯿﺴﻢ ﺑﯿﻤﺎرﯾﺰاﺋﯽ ﻫﻠﯿﮑﻮﺑﺎﮐﺘﺮ ﭘﯿﻠﻮري ﻋﺎﻣﻞ اﯾﺠﺎد زﺧﻢ ﻣﻌﺪه (1ﻧﻔﻮذ ﺑﺎﮐﺘﺮي ﺑﻪ ﻣﺨﺎط ﻣﻌﺪه ٢اﺗﺼﺎل وﺗﺮﺷﺢ ﺗﻮﻛﺴﯿﻦ (٣آزادﺳﺎزي ﺳﺎﯾﺘﻮﻛﺎﯾﻦ اﻟﺘﮭﺎﺑﻲ (٤واﻛﻨﺶ اﻟﺘﮭﺎﺑﻲ ﺗﻮﺳﻂ ﻧﻮﺗﺮوﻓﯿﻞ (٥ﺗﺨﺮﯾﺐ ﻣﺨﺎط ﺗﻮﺳﻂ آﻧﺰﯾﻢ ھﺎي ﺗﺮﺷﺤﻲ ﻧﻮﺗﺮوﻓﯿﻞ (٦ﺣﺴﺎﺳﯿﺖ ﺑﺎﻓﺖ ﺑﺪون ﭘﻮﺷﺶ ﺑﮫ اﺳﯿﺪ ﻣﻌﺪه)ﺗﺸﻜﯿﻞ زﺧﻢ ﻣﻌﺪه( STRUCTURES LOCATED OUTSIDE THE CELL WALL 2) Pili Pili are thin, protein tubes originating from the cytoplasmic membrane There are two basic types of pili: 1)short pili, also known as fimbriae(50-200n,5-10nm) GramFunction: Organelles of attachment :allowing bacteria to Colonize environmental surfaces 2) long pili, also called "F" or sex pili Function: conjugation :the transfer of DNA ﻧﻘﺶ ﭘﯿﻠﻲ)ﺟﺰءاﺗﺼﺎﻟﻲ( در ﺑﯿﻤﺎرﯾﺰاﺋﻲ ﺑﺎﻛﺘﺮﯾﮭﺎ ﻋﻔﻮﻧﺖ دﺳﺘﮕﺎه اداري ﺑﺎﻛﺘﺮي داراي ﭘﯿﻠﻲ :اﺗﺼﺎ ل ﻣﺤﻜﻢ ﺑﮫ ﻣﺨﺎط دﺳﺘﮕﺎه ادراري )اﯾﺠﺎد ﻋﻔﻮﻧﺖ ( ﺑﺎﻛﺘﺮي ﺑﺪون ﭘﯿﻠﻲ :ﺗﻮﺳﻂ ﺟﺮﯾﺎن ادرار ﺷﺴﺘﮫ ﻣﻲ ﺷﻮد )ﻋﺪم اﯾﺤﺎد ﻋﻔﻮﻧﺖ ( ﺗﺒﺎدل ژﻧﺘﯿﻜﻲ در ﺑﺎﻛﺘﺮﯾﮭﺎ (١اﺗﺼﺎل ﺑﺎﻛﺘﺮي دھﻨﺪه ژﻧﻮم )ﭘﻼﺳﻤﯿﺪ( ﺑﮫ ﺑﺎﻛﺘﺮي ﮔﯿﺮﻧﺪه از طﺮﯾﻖ ﭘﯿﻠﻲ ﺟﻨﺴﻲ (٢اﻧﺘﻘﺎل ﭘﻼﺳﻤﯿﺪ از طﺮﯾﻖ ﻛﺎﻧﺎل اﯾﺠﺎد ﺷﺪه (٣اﯾﺠﺎد ﺑﺎﻛﺘﺮي ﺟﺪﯾﺪ ﺣﺎوي ﭘﻼﺳﻤﯿﺪ وﭘﯿﻠﻲ ﺟﻨﺴﻲ ازطﺮﯾﻖ ﭘﯿﻠﻲ ﺟﻨﺴﻲ )ﮔﺎﻧﺠﻮﻛﺴﯿﻮن( STRUCTURES LOCATED OUTSIDE THE CELL WALL 3)Capsules ﭘﻠﯿﻤﺮ ﺧﺎرج ﺳﻠﻮﻟﯽ از ﺟﻨﺲ ﭘﻠﯽ ﺳﺎﮐﺎرﯾﺪ ﯾﺎ ﭘﺮوﺗﺌﯿﻦ ﮐﻪ ﺑﻪ ﺷﮑﻞ ﯾﮏ ﻻﯾﻪ ﻣﺘﺮاﮐﻢ در ﻣﺠﺎورت ﻧﺰدﯾﮏ ﺑﺎﮐﺘﺮي وﺟﻮد دارد ﮐﻪ ﻗﻄﺮ آن از 2/0ﻣﯿﮑﺮون ﺑﯿﺸﺘﺮ اﺳﺖ ﮐﻪ ﺑﻪ آن ﮐﭙﺴﻮل ﯾﺎ ﻣﺎﮐﺮوﮐﭙﺴﻮل ﻣﯽ ﮔﻮﯾﻨﺪ ‏Glycocalyx ﭼﻨﺎﻧﭽﻪ ﭘﻠﯿﻤﺮ از ﺷﺒﮑﻪ ﻓﺒﯿﺮﯾﻞ ﺳﺴﺘﯽ ﺑﻪ ﻃﺮف ﺧﺎرج ﺳﻠﻮل ﮐﺴﺘﺮش ﯾﺎﻓﺘﻪ در آﯾﺪ ﮐﻪ ﻗﻄﺮ آن از 2/0ﮐﻤﺘﺮ اﺳﺖ ‏Slim Layer در ﺑﺮرﺧﯽ ﻣﻮاردﺗﻮده ﻫﺎي ﭘﻠﯽ ﻣﺮي در ﺑﺎﮐﺘﺮﯾﻬﺎ ﺗﺸﮑﯿﻞ ﻣﯽ ﺷﻮﻧﺪ ﮐﻪ ﺑﻪ ﻧﻈﺮ ﮐﺎﻣﻼ از ﺳﻠﻮﻟﻬﺎ ﺟﺪا ﺷﺪه اﻧﺪ اﯾﻦ ﭘﻠﯿﻤﺮ ﺧﺎرج ﺳﻠﻮﻟﯽ را ﻻﯾﻪ ﻟﻌﺎﺑﯽ ﻣﯽ ﮔﻮﯾﻨﺪ Function: 1)Role of Capsule in resisting phagocytosis 2)Role of Glycocalyx in Attachment to celld 3) Antigenic Structure (و ﺻﺎفMucoid)ﺑﺎﮐﺘﺮﯾﻬﺎي ﮐﭙﺴﻮل دار ﮐﻠﻨﯽ ﻫﺎي ﻣﺮﻃﻮب ( وﻟﯽ ﺑﺎﮐﺘﺮﯾﻬﺎي ﺑﺬون ﮐﭙﺴﻮل ﮐﻠﻨﯽ ﻫﺎي ﺧﺸﮏSmooth) ( ﺗﻮﻟﯿﺪ ﻣﯽ ﮐﻨﻨﺪRough) (وﺧﺸﻦDry) ﻧﻘﺶ ﻛﭙﺴﻮل )ﭘﻮﺷﺶ ﭘﻠﻲ ﺳﺎﻛﺎرﯾﺪي اطﺮاف ﺑﺎﻛﺘﺮي( درﺑﯿﻤﺎرﯾﺰاﺋﻲ ﺑﺎﻛﺘﺮﯾﮭﺎو ﻓﺎﮔﻮﺳﯿﺘﻮز وﺟﻮد آﻧﺘﻲ ﺑﺎدي ﻋﻤﻞ ﻓﺎﮔﻮﺳﯿﺘﻮز را ﺗﺴﮭﯿﻞ ﻣﻲ ﻛﻨﺪ )ﭘﺪﯾﺪه اﭘﺴﻮﻧﯿﺰاﺳﯿﻮن( ﺳﻠﻮل ﺑﯿﮕﺎﻧﮫ ﺧﻮار )ﮔﻠﺒﻮل ﺳﻔﯿﺪ ( ﻗﺎدر ﺑﮫ ﺑﻠﯿﻌﺪن ﺑﺎﻛﺘﺮي ﻛﭙﺴﻮل دار ﻧﯿﺴﺖ (١اﺗﺼﺎل ﺑﺎﻛﺘﺮي ﺑﮫ ﺳﻠﻮل ﺑﯿﮕﺎﻧﮫ ﺧﻮار )ﮔﻠﺒﻮل ﺳﻔﯿﺪ ( از طﺮﯾﻖ آﻧﺘﻲ ﺑﺎدي (٣اﺗﺼﺎل ﻓﺎﮔﻮزوم ﺑﮫ ﻟﯿﺰوزوم (٢اﻧﻘﺒﺎض رﺷﺘﮫ ھﺎي اﻛﺘﯿﻦ وﺗﺸﻜﯿﻞ ﻓﺎﮔﻮزوم (٤ﻟﯿﺰ)ﻣﺮگ( ﺑﺎﻛﺘﺮي ﭘﺪﯾﺪه ﻓﺎﮔﻮﺳﯿﺘﻮز Cell Wall The Peptidoglycan Peptidoglycan , also called murein and Mucopeptide, is a polymer. A peptidoglycan monomer consists of two joined amino sugars 1) N-acetylglucosamine (NAG) 2) N-acetylmuramic acid (NAM), with a tetrapeptide The Peptidoglycan The Peptidoglycan ﺑﯿﻮﺳﻨﺘﺰ دﯾﻮاره ﺳﻠﻮﻟﻲ )ﻻﯾﮫ ﭘﭙﺘﯿﺪوﮔﻠﯿﮕﺎن( در ﺑﺎﻛﺘﺮﯾﮭﺎ (١ﺗﺸﻜﯿﻞ ﻣﻨﻮﻣﺮ ھﺎي ﺗﺸﻜﯿﻞ دھﻨﺪه دﯾﻮاره در ﺳﯿﺘﻮﭘﻼﺳﻢ (٢ﻋﺒﻮر واﺣﺪ ھﺎي ﺗﺸﻜﯿﻞ دھﻨﺪه دﯾﻮاره از ﻏﺸﺎء ﺳﻠﻮﻟﻲ ﺑﺎﮐﺘﻮﭘﺮﯾﻨﻮل (٣ﺷﻜﺎف در دﯾﻮاره ﺗﻮﺳﻂ آﻧﺰﯾﻢ ھﺎي اﺗﻮﻟﯿﺰ ﻛﻨﻨﺪه (٤ورود واﺣﺪھﺎي ﺗﺸﻜﯿﻞ دھﻨﺪه ﺑﮫ دﯾﻮاره ﺳﻠﻮﻟﻲ (٥اﯾﺠﺎد ﭘﯿﻮﻧﺪ ﮔﻠﯿﻜﻮزﯾﺪي ﺑﯿﻦ واﺣﺪھﺎي ﺗﺸﻜﯿﻞ دھﻨﺪه (٦ﺗﺸﻜﯿﻞ ﭘﯿﻮﻧﺪ ﭘﻞ ﻣﺎﻧﻨﺪ ﺑﯿﻦ زﻧﺠﯿﺮھﺎي ﺗﻮﺳﻂ آﻧﺰﯾﻢ ﺗﺮاﻧﺲ ﭘﭙﺘﯿﺪاز Special Components of Gram Negative Bacteria 1)Outer Membrane Bilayer Structure Resembles Cytoplasmic Membrane Has Special Channels :Porin ,Permit the Passive Diffusion Suger ,Amino Acids and Ions 2) Lipoprotein Cross-Linked the Outer Membrane and Peptidoglycan 57 Amino acids -DAP 3) Peri plasmic space : Space between cell membrane and Outer Membrane Special Components of Gram Negative Bacteria 3)Lipopolysaccharids( LPS) A) Lipid A: EndoToxins B) polysaccharid Core C) Antigen O Special Components of Gram Positive Bacteria 1) Teichoic acids Water –Soluble Plomers , Ribitol or Glycerol Cell Teichoic acids ,LipoTeichoic acids Surface antigen ,Facilitate the Attachment to Host Cell Binds to Magnesium Ion Receptor for Phage 2) PolySaccharides Mannose , Arabinose,Galactose,Rhamnose Antigenic Structure ﻋﻮاﻣﻞ ﻣﻮﺛﺮ ﺑﺮ دﯾﻮاره ﻣﺎﻧﻨﺪ ﻟﯿﺰوزﯾﻢ وﭘﻨﯽ ﺳﯿﻠﯿﻦ ﺑﺎﻋﺚ ازﺑﯿﻦ رﻓﺘﻦ دﯾﻮاره ﺳﻠﻮﻟﯽ ﻣﯽ ﺷﻮد ﭘﺮوﺗﻮﭘﻼﺳﺖ ) G+ (Protoplastﮐﺎﻣﻞ اﺳﻔﺮوﭘﻼﺳﺖ ) G-(Spheroplastﻗﺴﻤﺘﯽ اﺷﮑﺎل G-( L forms) Lﮔﺮوي ،ﻣﻘﺎوم ﺑﻪ آﻧﺘﯽ ﺑﯿﻮﺗﯿﮏ ﺑﺮﮐﺸﺖ ﺑﻪ ﺣﺎﻟﺖ اول Mycobacterium . Tuberculosis Cell wall peptidoglycan Arabinogalactan (D-arabinose and D-galactose) which is then linked to high-molecular weight mycolic acids. In addition to, the acid-fast cell wall of Mycobacterium contains a large amount of glycolipids, especially mycolic acids.(C78-C90) + Trehalose dimycolate ( Cord Factor ) Inhibite phagocytosis (phagosome lysosome fusion) M. Tuberculosis Cell wall Other glycolipids include Lipoarabinomannan and phosphatidyl inositol mannosides (PIM). Lipoarabinomannan, also called LAM, is a glycolipid, and a virulence factor associated with tuberculosis. Its primary function is to inactivate macrophages and destruction of oxidative radicals. These mechanisms include the inhibition of T-cell proliferation and of macrophage microbicidal activity via diminished IFN-γ response. PIMs influence the interaction of the immune system with M. tuberculosis, that develop antibodies. Cytoplasmic (Cell) Membrane Bilayer Structure:Phosholipids and Protein P:60-70% L:30-40% without-Sterol (mycoplasma) Function: 1)Permeability and Transport 2)Electron Transport Chain,Oxidative Phoshorylation 3)Enzyme and Carrier molecules :in biosynthesis of DNA, Cell wall Polymers and Membrane Lipids 4) Chemoreceptor The Cytoplasm Composition: In bacteria, the cytoplasm refers to everything enclosed by the cytoplasmic membrane. About 80% of the cytoplasm of bacteria is composed of water. Within the cytoplasm can be found nucleic acids (DNA and RNA), enzymes and amino acids, carbohydrates, lipids, inorganic ions, and many low molecular weight compounds. The liquid component of the cytoplasm is called the cytosol The Nucleoid Composition: The term genome refers to the sum of an organism's genetic material. The bacterial genome is composed of chromosomal deoxyribonucleic acid or DNA and represents the bacterium's nucleoid. Unlike the eukaryotic nucleus, the bacterial nucleoid has no nuclear membrane or nucleoli Endospores A resistant form of the organism Endospores are quite resistant to high temperatures (including boiling), most disinfectants, low energy radiation, drying Sporulation: Change ,Active Bacteria to Spore Germination : Change ,Spore to Active Bacteria Size of Spore:0.2-2 Micron Endospores Structure : The completed endospore consists of multiple layers including: 1)Core:surrounding a nucleoid, some ribosomes, RNA molecules, and enzymes 2)Spore Wall 3) Cortex: The thickest layer ,like of PG with fewer crosslink 4) Spore coat: Keratin-like Protein ,Resistance to Chemical material 5) Exosporium:Lipoprotein some Carbohydrate The heat resistance of endospores is due to a variety of factors: •Calcium-dipicolinate, abundant within the endospore, may stabilize and protect the endospore's DNA. •Specialized DNA-binding proteins saturate the endospore's DNA and protect it from heat, drying, chemicals, and radiation. •The cortex may osmotically remove water from the interior of the endospore and the dehydration that results is thought to be very important in the endospore's resistance to heat and radiation. Formation of endospores: Under conditions of starvation, especially the lack of carbon and nitrogen sources, a single endospores form within some of the bacteria. The process is called sporulation. First the DNA replicates and a cytoplasmic membrane septum forms at one end of the cell. A second layer of cytoplasmic membrane then forms around one of the DNA molecules (the one that will become part of the endospore) to form a forespore. Formation of endospores: Both of these membrane layers then synthesize peptidoglycan in the space between them to form the first protective coat, the cortex. A spore coat composed of a keratin-like protein then forms around the cortex. Sometimes an outer membrane composed of lipid and protein and called an exosporium is also seen.