logging in or signing up Morphlogy of Bacteria Patanvadia Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1566 Category: Entertainment License: All Rights Reserved Like it (4) Dislike it (0) Added: March 30, 2010 This Presentation is Public Favorites: 2 Presentation Description No description available. Comments Posting comment... By: saurabhkumarjauhari (8 month(s) ago) nice presentation kindly permit to download Saving..... Post Reply Close Saving..... Edit Comment Close By: hamadaalasd (18 month(s) ago) شكرا Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Morphology and Physiology of Bacteria : Morphology and Physiology of Bacteria Department Of Pathology D.D.University Faculty of Dental Science, College road, Nadiad. Slide 2: Microorganism are a hetrogenous group of distinct classes of living beings. Classification--- 1)plant 2) animal kingdom. Third kingdom-Protista. It again divide in two group 1)prokaryotes 2) eukaryotes. Bacteria and blue green algae are prokaryotes, fungi and other algae, protozoa are eukaryotes. Size of Bacteria. : Size of Bacteria. Unit in bacteriology is micron (micrometer) 1u= one thousand of millimeter. 1 millimeter or nanometer = one thousandth of a micron. 1 Angstrom unit = one tenth of nanometer. For medical importance size is 0.2-1.5 um and length 3-5 um . Microscopy . : Microscopy . Type of microscope employed. Optical or Light microscope Phase contrast microscopy Dark field / Dark ground microscope: the contrast gives an illusion of increased resolution so that very slender organisms such as spirochetes, not seen by ordinary microscope is illuminated. Electron microscope. Staining . : Staining . Stained Preparations-Bacteria have an affinity for basic dyes due to acidic nature of their protoplasm. Simple stains: dye like methylene blue or basic fuschin. Provide colour contrast but give same colour to all bacteria. Negative staining: bacteria are mixed with dye such as India ink. Demonstrates bacterial capsules for ex pneumococci. Slide 8: Impregnation method: cell and structure is impregnated with silver on the surface. Such method use for demonstration of spirochetes and bacterial flagella. : Differential stains: The most widely used differential stains are 1) Gram stain 2) acid fast stain. Gram stain –devised by Christian Gram 1884. 4 STEPS. Primary staining : dye like crystal violet, gention violet, Application of dilute solution of iodine. Decolourisation with acetone Counterstaining with safranine. Gram stain. : Gram stain. Gram stain differentiate bacteria in two broad groups. Gram positive – resist decolorization. It retain primary stain and appears violet. Gram negative – decolorized by organic solvent and takes counter stain appear red. Gram positive cells have more acidic protoplasm which account for their retaining primary dye more strongly. Slide 12: The Gram reaction may be related to the permeability of the bacterial cell wall and cytoplasmic membrane to the dye iodine complex. Gram negative permitting the outflow of the complex during decolorisation. Gram reactivity is of importance as the gram positive and negative difference by staining characteristic, growth requirment,succptibility to antibiotics and pathogenicity. Acid Fast Stain : Acid Fast Stain Acid fast stain discovered by Ehrlich. Method common in use is Modified Ziehl and Neelsen. Smear stain by a strong solution of carbol fuschin with application of heat. Decolorized with 20% H2SO4. Counter stain is methylene blue. Acid fast bacteria appear red, other take counter stains Slide 14: A lipid peculiar to acid fast bacilli, high molecular weight hydroxy acid wax containing carboxyl group(mycolic acid) is acid fast and responsible for red colour. Shape Of Bacteria. : Shape Of Bacteria. Depending on their shape bacteria are classified into several group. 1 - cocci - kokkos means berry—oval 2 - Bacilli--- Bacillus means rod– rod shape 3 - vibrios—comma shape 4 - spirilla are rigid spiral forms. 5 - Spirochetes are spiral forms 6 - Actinomycetes are branching filamentous bacteria. 7 - Mycoplasma are bacteria that are cell wall deficient. Occur as round or oval bodies. Slide 18: Bacteria sometime show cellular arrangement or grouping. Cocci arranged in pairs (diplococci),chains (streptococci), group of four (tetrads) or eight (sarcina), or grape-like clusters (staphylococci). Slide 19: Bacilli arranged in chains (streptobacilli) Chinese letter pattern (corny bacteria) Bacteria are divided through binary fission and have tendency of the daughter cell to remain attached even after division. Bacterial Anatomy. : Bacterial Anatomy. The cell wall: The cell wall accounts for the shape of bacterial cell and confers on it rigidity and ductility. It may be demonstrated by plasmolysis. Also demonstrated by micro dissection, rxn with specific antibody or by electron microscopy. Slide 23: Bacterial cell wall are about 10-25 mm thick. Chemically composed of mucopeptide (peptidoglycan) scaffolding formed by N Acetyl Glucose amine and N Acetyl Muramic acid molecules alternating in chains which are cross linked by peptide chains. Comparison of cell wall : Comparison of cell wall Cytoplasmic Membrane. : Cytoplasmic Membrane. It is thin 5-10 nm. It is a layer lining the inner surface of the cell wall and separating it from the cytoplasm. Acts as semi permeable membrane, regulates Inflow and outflow of metabolites to and from protoplasm. Electron microscopy shows presence of three layers constituting a ‘unit membrane’ structure. Chemically consists of lipoprotein with small amount of carbohydrate. Sterols absent except mycoplasma Cytoplasm. : Cytoplasm. The bacterial cytoplasm is a colloidal system of a variety of organic and inorganic solutes in a viscous watery solution. Stains with basic dyes in young culture but becomes granular with age. It contains ribosomes, mesosomes, inclusions and vacuoles. Ribosomes. : Ribosomes. It are centre of protein synthesis. Slightly smaller then the ribosomes of eukaryotic cells (sedimentation constant 70 S) It is integrated in linear strands of mRNA to form polysomes. Mesosomes. : Mesosomes. Vesicular, convoluted or multilaminated structures formed as invagination of the plasma membrane into the cytoplasm. More prominent in gram positive bacteria. Mesosomes are seen in relation to the nuclear body and the site of synthesis of cross wall septa , suggesting that they coordinate nuclear and cytoplasmic division during binary fission Intra cytoplasmic inclusions. : Intra cytoplasmic inclusions. Various type chief is Volutin, lipid & crystals. Volutin granules (met achromatic or Babes –Ernst granules) are highly refractive, strongly basophilic bodies. Special staining technique such as Albert's stain or Neisser”s stain. Characteristic of diphtheria bacilli. Nucleus. : Nucleus. Bacterial nuclei have no nuclear membrane or nucleolus. The genome consists of single strand of DNA arranged in the form of circle, which may open under certain condition to form a long chain about 1 mm in length. Slime layer and Capsule. : Slime layer and Capsule. Many bacteria secrete a viscid material around the cell surface. When this organized into sharply defined structure, as in the pneumococcus, it is known as the capsule. When it is loose undemarcated secretion as in leuconostoc, it is called as the slime layer. Bacteria secreting large amount of slime produce mucoid growth on agar. Capsule Demonstration : Capsule Demonstration Negative stain like India ink for capsule demonstration. Serological method. Quelling rxn. Useful for typing of pneumococci. Flagella. : Flagella. Organ of locomotion. Three part. 1) filament 2) the hook 3) the basal body. 3-20 um long and are of uniform diameter. Flagella may arrange in peritrichous form as in typhoid bacilli or polar as in cholera vibrio. Fimbriae. : Fimbriae. Hair like surface appendages called fimbriae or pili. Fimbriae function as organ of adhesion. Hemaagglutination provides a simple method for detection of fimbriae. Spore. : Spore. Some bacteria particularly genera bacillus and clostridium have ability to form highly resistant form called spores. It may be central (equatorial), terminal, or sub terminal. It may be oval or spherical. Destroyed by autoclaving at 120 degree C for 15 minutes. Bacterial growth curve. : Bacterial growth curve. When bacterium is seeded into a suitable liquid medium and incubated its growth follows a definite course. If bacterial counts are made at intervals after inoculation and plotted in relation to time a growth curve is obtained. Phase of growth curve : Phase of growth curve Following phase: Lag phase - increase in the size of the cell. It is the time require for adaption of new environment. Log phase - cell start dividing and their number increases exponentially. Stationary phase - cell division stops due to depletion of nutrients and accumulation of toxic products. Phase of decline – population decrease due to cell death. Slide 46: Bacteria have the maximum cell size toward the end of the lag phase. In the log phase cells are smaller and stain uniformly. In stationary phase cells frequently are Gram variable and show irregular staining due to presence of intracellular storage granules. sporulation occur at this stage. Bacterial nutrition. : Bacterial nutrition. 80% of total weight of bacteria is water. Protein, polysaccharides, lipids, nucleic acids, mucopeptide make up the rest. Bacteria derive their energy from sunlight are called phototrophs and from chemical reaction are called chemotrophs. Bacteria that can synthesize all their organic compound called autotrophs. Those depend on preformed organic compound are called heterotrophy. Oxygen requirement. : Oxygen requirement. Aerobic - require oxygen for growth. they may be obligate aerobe like cholera vibrio which grow only in +nce of oxygen or facultative anaerobes also grow in absence of oxygen. Most bacteria of medical importance are facultative anaerobes. Anaerobic - such as clostridia grow in absence of oxygen and obligate anaerobes may even die on exposure to oxygen. Micro aerophilic - grow best in the presence of low oxygen tension Carbon dioxide : Carbon dioxide All bacteria require small amount of carbon dioxide for growth. Some bacteria like Brucella abortus require higher level of carbon dioxide for their growth. Temperature : Temperature Optimum temperature which in the case of most pathogenic bacteria is 37°C. Mesophilic bacteria grow at temp. of 25 - 40°C. Psychrophilic bacteria grow best at temp. below 20°C. Other factors. : Other factors. Moisture and drying. Water is essential ingredient of bacterial protoplasm hence drying is lethal to cells. H-ion concentration. The majority if pathogenic bacteria at Ph 7.2-7.6 . Light . Bacteria except the phototrophic species grow well in dark. Mechanical stress. Bacteria may rupture by mechanical stress like grinding or vigorous shaking with glass beads. You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Morphlogy of Bacteria Patanvadia Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1566 Category: Entertainment License: All Rights Reserved Like it (4) Dislike it (0) Added: March 30, 2010 This Presentation is Public Favorites: 2 Presentation Description No description available. Comments Posting comment... By: saurabhkumarjauhari (8 month(s) ago) nice presentation kindly permit to download Saving..... Post Reply Close Saving..... Edit Comment Close By: hamadaalasd (18 month(s) ago) شكرا Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Morphology and Physiology of Bacteria : Morphology and Physiology of Bacteria Department Of Pathology D.D.University Faculty of Dental Science, College road, Nadiad. Slide 2: Microorganism are a hetrogenous group of distinct classes of living beings. Classification--- 1)plant 2) animal kingdom. Third kingdom-Protista. It again divide in two group 1)prokaryotes 2) eukaryotes. Bacteria and blue green algae are prokaryotes, fungi and other algae, protozoa are eukaryotes. Size of Bacteria. : Size of Bacteria. Unit in bacteriology is micron (micrometer) 1u= one thousand of millimeter. 1 millimeter or nanometer = one thousandth of a micron. 1 Angstrom unit = one tenth of nanometer. For medical importance size is 0.2-1.5 um and length 3-5 um . Microscopy . : Microscopy . Type of microscope employed. Optical or Light microscope Phase contrast microscopy Dark field / Dark ground microscope: the contrast gives an illusion of increased resolution so that very slender organisms such as spirochetes, not seen by ordinary microscope is illuminated. Electron microscope. Staining . : Staining . Stained Preparations-Bacteria have an affinity for basic dyes due to acidic nature of their protoplasm. Simple stains: dye like methylene blue or basic fuschin. Provide colour contrast but give same colour to all bacteria. Negative staining: bacteria are mixed with dye such as India ink. Demonstrates bacterial capsules for ex pneumococci. Slide 8: Impregnation method: cell and structure is impregnated with silver on the surface. Such method use for demonstration of spirochetes and bacterial flagella. : Differential stains: The most widely used differential stains are 1) Gram stain 2) acid fast stain. Gram stain –devised by Christian Gram 1884. 4 STEPS. Primary staining : dye like crystal violet, gention violet, Application of dilute solution of iodine. Decolourisation with acetone Counterstaining with safranine. Gram stain. : Gram stain. Gram stain differentiate bacteria in two broad groups. Gram positive – resist decolorization. It retain primary stain and appears violet. Gram negative – decolorized by organic solvent and takes counter stain appear red. Gram positive cells have more acidic protoplasm which account for their retaining primary dye more strongly. Slide 12: The Gram reaction may be related to the permeability of the bacterial cell wall and cytoplasmic membrane to the dye iodine complex. Gram negative permitting the outflow of the complex during decolorisation. Gram reactivity is of importance as the gram positive and negative difference by staining characteristic, growth requirment,succptibility to antibiotics and pathogenicity. Acid Fast Stain : Acid Fast Stain Acid fast stain discovered by Ehrlich. Method common in use is Modified Ziehl and Neelsen. Smear stain by a strong solution of carbol fuschin with application of heat. Decolorized with 20% H2SO4. Counter stain is methylene blue. Acid fast bacteria appear red, other take counter stains Slide 14: A lipid peculiar to acid fast bacilli, high molecular weight hydroxy acid wax containing carboxyl group(mycolic acid) is acid fast and responsible for red colour. Shape Of Bacteria. : Shape Of Bacteria. Depending on their shape bacteria are classified into several group. 1 - cocci - kokkos means berry—oval 2 - Bacilli--- Bacillus means rod– rod shape 3 - vibrios—comma shape 4 - spirilla are rigid spiral forms. 5 - Spirochetes are spiral forms 6 - Actinomycetes are branching filamentous bacteria. 7 - Mycoplasma are bacteria that are cell wall deficient. Occur as round or oval bodies. Slide 18: Bacteria sometime show cellular arrangement or grouping. Cocci arranged in pairs (diplococci),chains (streptococci), group of four (tetrads) or eight (sarcina), or grape-like clusters (staphylococci). Slide 19: Bacilli arranged in chains (streptobacilli) Chinese letter pattern (corny bacteria) Bacteria are divided through binary fission and have tendency of the daughter cell to remain attached even after division. Bacterial Anatomy. : Bacterial Anatomy. The cell wall: The cell wall accounts for the shape of bacterial cell and confers on it rigidity and ductility. It may be demonstrated by plasmolysis. Also demonstrated by micro dissection, rxn with specific antibody or by electron microscopy. Slide 23: Bacterial cell wall are about 10-25 mm thick. Chemically composed of mucopeptide (peptidoglycan) scaffolding formed by N Acetyl Glucose amine and N Acetyl Muramic acid molecules alternating in chains which are cross linked by peptide chains. Comparison of cell wall : Comparison of cell wall Cytoplasmic Membrane. : Cytoplasmic Membrane. It is thin 5-10 nm. It is a layer lining the inner surface of the cell wall and separating it from the cytoplasm. Acts as semi permeable membrane, regulates Inflow and outflow of metabolites to and from protoplasm. Electron microscopy shows presence of three layers constituting a ‘unit membrane’ structure. Chemically consists of lipoprotein with small amount of carbohydrate. Sterols absent except mycoplasma Cytoplasm. : Cytoplasm. The bacterial cytoplasm is a colloidal system of a variety of organic and inorganic solutes in a viscous watery solution. Stains with basic dyes in young culture but becomes granular with age. It contains ribosomes, mesosomes, inclusions and vacuoles. Ribosomes. : Ribosomes. It are centre of protein synthesis. Slightly smaller then the ribosomes of eukaryotic cells (sedimentation constant 70 S) It is integrated in linear strands of mRNA to form polysomes. Mesosomes. : Mesosomes. Vesicular, convoluted or multilaminated structures formed as invagination of the plasma membrane into the cytoplasm. More prominent in gram positive bacteria. Mesosomes are seen in relation to the nuclear body and the site of synthesis of cross wall septa , suggesting that they coordinate nuclear and cytoplasmic division during binary fission Intra cytoplasmic inclusions. : Intra cytoplasmic inclusions. Various type chief is Volutin, lipid & crystals. Volutin granules (met achromatic or Babes –Ernst granules) are highly refractive, strongly basophilic bodies. Special staining technique such as Albert's stain or Neisser”s stain. Characteristic of diphtheria bacilli. Nucleus. : Nucleus. Bacterial nuclei have no nuclear membrane or nucleolus. The genome consists of single strand of DNA arranged in the form of circle, which may open under certain condition to form a long chain about 1 mm in length. Slime layer and Capsule. : Slime layer and Capsule. Many bacteria secrete a viscid material around the cell surface. When this organized into sharply defined structure, as in the pneumococcus, it is known as the capsule. When it is loose undemarcated secretion as in leuconostoc, it is called as the slime layer. Bacteria secreting large amount of slime produce mucoid growth on agar. Capsule Demonstration : Capsule Demonstration Negative stain like India ink for capsule demonstration. Serological method. Quelling rxn. Useful for typing of pneumococci. Flagella. : Flagella. Organ of locomotion. Three part. 1) filament 2) the hook 3) the basal body. 3-20 um long and are of uniform diameter. Flagella may arrange in peritrichous form as in typhoid bacilli or polar as in cholera vibrio. Fimbriae. : Fimbriae. Hair like surface appendages called fimbriae or pili. Fimbriae function as organ of adhesion. Hemaagglutination provides a simple method for detection of fimbriae. Spore. : Spore. Some bacteria particularly genera bacillus and clostridium have ability to form highly resistant form called spores. It may be central (equatorial), terminal, or sub terminal. It may be oval or spherical. Destroyed by autoclaving at 120 degree C for 15 minutes. Bacterial growth curve. : Bacterial growth curve. When bacterium is seeded into a suitable liquid medium and incubated its growth follows a definite course. If bacterial counts are made at intervals after inoculation and plotted in relation to time a growth curve is obtained. Phase of growth curve : Phase of growth curve Following phase: Lag phase - increase in the size of the cell. It is the time require for adaption of new environment. Log phase - cell start dividing and their number increases exponentially. Stationary phase - cell division stops due to depletion of nutrients and accumulation of toxic products. Phase of decline – population decrease due to cell death. Slide 46: Bacteria have the maximum cell size toward the end of the lag phase. In the log phase cells are smaller and stain uniformly. In stationary phase cells frequently are Gram variable and show irregular staining due to presence of intracellular storage granules. sporulation occur at this stage. Bacterial nutrition. : Bacterial nutrition. 80% of total weight of bacteria is water. Protein, polysaccharides, lipids, nucleic acids, mucopeptide make up the rest. Bacteria derive their energy from sunlight are called phototrophs and from chemical reaction are called chemotrophs. Bacteria that can synthesize all their organic compound called autotrophs. Those depend on preformed organic compound are called heterotrophy. Oxygen requirement. : Oxygen requirement. Aerobic - require oxygen for growth. they may be obligate aerobe like cholera vibrio which grow only in +nce of oxygen or facultative anaerobes also grow in absence of oxygen. Most bacteria of medical importance are facultative anaerobes. Anaerobic - such as clostridia grow in absence of oxygen and obligate anaerobes may even die on exposure to oxygen. Micro aerophilic - grow best in the presence of low oxygen tension Carbon dioxide : Carbon dioxide All bacteria require small amount of carbon dioxide for growth. Some bacteria like Brucella abortus require higher level of carbon dioxide for their growth. Temperature : Temperature Optimum temperature which in the case of most pathogenic bacteria is 37°C. Mesophilic bacteria grow at temp. of 25 - 40°C. Psychrophilic bacteria grow best at temp. below 20°C. Other factors. : Other factors. Moisture and drying. Water is essential ingredient of bacterial protoplasm hence drying is lethal to cells. H-ion concentration. The majority if pathogenic bacteria at Ph 7.2-7.6 . Light . Bacteria except the phototrophic species grow well in dark. Mechanical stress. Bacteria may rupture by mechanical stress like grinding or vigorous shaking with glass beads.