1 Applied Microbiology 3 nd lecture: Chapter 4. 2 Prokaryotic Cells Characteristics of Cells and...

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Applied MicrobiologyApplied Microbiology

33ndnd lecture: Chapter lecture: Chapter 44

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Prokaryotic CellsProkaryotic Cells

Characteristics of Cells and LifeCharacteristics of Cells and Life

All living things (single and multicellular) are made of cells All living things (single and multicellular) are made of cells that share some common characteristics:that share some common characteristics:

- basic shape – spherical, cubical, cylindrical- basic shape – spherical, cubical, cylindrical

- internal content – - internal content – cytoplasmcytoplasm, surrounded by a , surrounded by a membranemembrane-DNA chromosome(s), ribosomes, metabolic capabilitiesDNA chromosome(s), ribosomes, metabolic capabilities

Two basic cell types: Two basic cell types: eukaryoticeukaryotic and and prokaryoticprokaryotic

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Characteristics of CellsCharacteristics of Cells

Eucaryotic cellsEucaryotic cells: animals, plants, fungi, and protists: animals, plants, fungi, and protists- contain double-membrane bound contain double-membrane bound nucleusnucleus with DNA with DNA

chromosomeschromosomes- contain membrane-bound contain membrane-bound organellesorganelles that that

compartmentalize the cytoplasmcompartmentalize the cytoplasm and perform and perform specificspecific

functionsfunctions

Procaryotic cellsProcaryotic cells: bacteria and archaea : bacteria and archaea

- no nucleus or other membrane-bound organelles- no nucleus or other membrane-bound organelles

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Characteristics of LifeCharacteristics of LifeWhat is life ?

- Growth and developmentGrowth and development

- Reproduction and heredity – Reproduction and heredity – genomegenome composed of DNA packed in composed of DNA packed in chromosomes; produce offspring sexually or asexuallychromosomes; produce offspring sexually or asexually

- Metabolism – chemical and physical life processesMetabolism – chemical and physical life processes

- Movement and/or irritability – respond to internal/external stimuli;Movement and/or irritability – respond to internal/external stimuli; self-propulsion of many organismsself-propulsion of many organisms

- Cell support, protection, and storage mechanisms – cell walls, Cell support, protection, and storage mechanisms – cell walls, vacuoles, vacuoles, granules and inclusionsgranules and inclusions

- Transport of nutrients and wasteTransport of nutrients and waste

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Prokaryotic Profiles: Bacteria and ArchaeaProkaryotic Profiles: Bacteria and Archaea

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Prokaryotic Profiles: Bacteria and ArchaeaProkaryotic Profiles: Bacteria and Archaea

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External StructuresExternal Structures

- Appendages- Appendages

two major groups of appendages:two major groups of appendages:- Motility – flagella and axial filaments (periplasmicMotility – flagella and axial filaments (periplasmic

flagella)flagella)- Attachment or channels – fimbriae and piliAttachment or channels – fimbriae and pili

- Glycocalyx – surface coating- Glycocalyx – surface coating

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External Structures - FlagellaExternal Structures - Flagella

3 parts:3 parts:

1. filament1. filament – long, thin, helical structure composed of – long, thin, helical structure composed of proteinprotein

flagellinflagellin

2. hook2. hook- curved sheath- curved sheath

3. basal body3. basal body – stack of rings firmly anchored in cell wall – stack of rings firmly anchored in cell wall

Rotates 360Rotates 360oo

Number and arrangement of flagella varies:Number and arrangement of flagella varies:

monotrichous, lophotrichous, amphitrichous, peritrichousmonotrichous, lophotrichous, amphitrichous, peritrichous

-> Functions in motility of cell through environment-> Functions in motility of cell through environment

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External Structures - FlagellaExternal Structures - Flagella

Gram-negative Gram-positive

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Prokaryotic CellsProkaryotic CellsExternal Structures – Flagella External Structures – Flagella

ArrangementsArrangements

Monotrichous – single flagellum at one endMonotrichous – single flagellum at one end

Lophotrichous – small bunches arising from one end of Lophotrichous – small bunches arising from one end of cellcell

Amphitrichous – flagella at both ends of cellAmphitrichous – flagella at both ends of cell

Peritrichous – flagella dispersed over surface of cell; Peritrichous – flagella dispersed over surface of cell; slowestslowest

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Prokaryotic CellsProkaryotic CellsExternal Structures – Flagella External Structures – Flagella

ArrangementsArrangements

MonotrichousMonotrichous LophotrichousLophotrichous

AmphitrichousAmphitrichous PeritrichousPeritrichous

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External Structures – Operation of FlagellaExternal Structures – Operation of Flagella

counterclockwiscounterclockwise –> results in e –> results in smooth linear smooth linear direction – direction – runrun

clockwise -> cell stops clockwise -> cell stops and and tumblestumbles

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External Structures – Flagella FunctionExternal Structures – Flagella Function

Guide bacteria in a direction in response to external stimulus: Guide bacteria in a direction in response to external stimulus:

-> chemical stimuli – -> chemical stimuli – chemotaxischemotaxis; positive and negative; positive and negative-> light stimuli – -> light stimuli – phototaxisphototaxis

Signal sets flagella into rotary motion clockwise or Signal sets flagella into rotary motion clockwise or counterclockwise:counterclockwise:

-> counterclockwise – results in smooth linear direction – -> counterclockwise – results in smooth linear direction – runrun-> clockwise - -> clockwise - tumblestumbles

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External Structures – ChemotaxisExternal Structures – Chemotaxis

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External Structures – Axial FilamentsExternal Structures – Axial Filaments

Periplasmic, internal Periplasmic, internal flagella, enclosed flagella, enclosed between cell wall and between cell wall and cell membrane of cell membrane of spirochetesspirochetes

Produce cellular motility Produce cellular motility by contracting and by contracting and imparting twisting or imparting twisting or flexing motionflexing motion

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Prokaryotic CellsProkaryotic CellsExternal Structures – Other Appendages: External Structures – Other Appendages:

FimbriaeFimbriae

Fine, proteinaceous, hairlike Fine, proteinaceous, hairlike bristles from the cell bristles from the cell surfacesurface

Function in adhesion to Function in adhesion to other cells and surfacesother cells and surfaces

-> do not provide -> do not provide locomotionlocomotion

-> pathogens use it to -> pathogens use it to attach tightly to epithelial attach tightly to epithelial cells -> infectioncells -> infection

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Prokaryotic CellsProkaryotic CellsExternal Structures – Other Appendages: External Structures – Other Appendages:

PiliPili

Rigid tubular structure Rigid tubular structure made of made of pilinpilin protein protein

Found only in Gram Found only in Gram negative cellsnegative cells

Function to join bacterial Function to join bacterial cells for partial DNA cells for partial DNA transfer called transfer called conjugationconjugation

-> sex pili-> sex pili

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External Structures – GlycocalyxExternal Structures – GlycocalyxCoating of molecules external to the cell wall, Coating of molecules external to the cell wall,

-> made of -> made of sugars and/or proteinssugars and/or proteins

Two types:Two types:

-> slime layer - loosely organized and -> slime layer - loosely organized and attachedattached

-> capsule - highly organized, tightly -> capsule - highly organized, tightly attachedattached

Functions:Functions:

-> protect cells from dehydration and -> protect cells from dehydration and nutrient lossnutrient loss

-> inhibit killing by white blood cells by -> inhibit killing by white blood cells by phagocytosis contributing to phagocytosis contributing to pathogenicity pathogenicity

-> attachment - formation of -> attachment - formation of biofilmsbiofilms

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Prokaryotic CellsProkaryotic CellsExternal Structures – Glycocalyx -> External Structures – Glycocalyx ->

BiofilmsBiofilms

Staphylococcus aureus

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The Cell EnvelopeThe Cell Envelope

-> External covering outside the cytoplasm-> External covering outside the cytoplasm

-> Composed of two basic layers:-> Composed of two basic layers:cell wallcell wall and and cell membranecell membrane

-> Maintains cell integrity-> Maintains cell integrity

-> Two generally different groups of bacteria -> Two generally different groups of bacteria demonstrateddemonstrated by by Gram stainGram stain::

Gram-positive bacteriaGram-positive bacteria: thick cell wall composed : thick cell wall composed primarily of peptidoglycan and cell membraneprimarily of peptidoglycan and cell membrane

Gram-negative bacteriaGram-negative bacteria: outer cell membrane, thin : outer cell membrane, thin peptidoglycan layer, and cell membranepeptidoglycan layer, and cell membrane

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The Cell Envelope: Cell WallThe Cell Envelope: Cell Wall

-> Determines cell shape, prevents -> Determines cell shape, prevents lysis lysis (bursting) or (bursting) or collapsingcollapsing

due to changing osmotic pressuresdue to changing osmotic pressures

PeptidoglycanPeptidoglycan is primary component: is primary component:

unique macromolecule composed of a repeating unique macromolecule composed of a repeating framework of long glycan chains cross-linked by short framework of long glycan chains cross-linked by short peptide fragmentspeptide fragments

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The Cell Envelope: Cell WallThe Cell Envelope: Cell WallPeptidoglycPeptidoglycanan

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The Cell Envelope: Gram-Positive Cell WallThe Cell Envelope: Gram-Positive Cell WallThick, homogeneous sheath of peptidoglycanThick, homogeneous sheath of peptidoglycan

-> 20-80 nm thick-> 20-80 nm thick

-> includes -> includes teichoic acidteichoic acid and and lipoteichoic acidlipoteichoic acid: function in cell: function in cell

wall maintenance and enlargement during cell division; move wall maintenance and enlargement during cell division; move

cations across the cell envelope; stimulate a specific immunecations across the cell envelope; stimulate a specific immune

responseresponse

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Prokaryotic CellsProkaryotic CellsThe Cell Envelope: Gram-Negative Cell The Cell Envelope: Gram-Negative Cell

WallWall-> Composed of an -> Composed of an outer membraneouter membrane and a thin peptidoglycan layer and a thin peptidoglycan layer

-> Protective structure while providing some flexibility and sensitivity to lysis-> Protective structure while providing some flexibility and sensitivity to lysis

-> -> Periplasmic space Periplasmic space surrounds peptidoglycansurrounds peptidoglycan

-> Outer membrane is similar to cell membrane bilayer structure -> Outer membrane is similar to cell membrane bilayer structure - outermost layer contains - outermost layer contains lipopolysaccharides lipopolysaccharides and and lipoproteins (LPS)lipoproteins (LPS)

> endotoxin that may become toxic when released during infections> endotoxin that may become toxic when released during infections> may function as receptors and blocking immune response> may function as receptors and blocking immune responsecontains contains porinporin proteins in upper layer – regulate molecules entering and proteins in upper layer – regulate molecules entering and leavingleaving cell cell

-Bottom layer composed of phospholipids and lipoproteinsBottom layer composed of phospholipids and lipoproteins

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Prokaryotic CellsProkaryotic CellsThe Cell Envelope: Gram-Negative Cell The Cell Envelope: Gram-Negative Cell

WallWall

Porin (channel for small molecule passage).Porin (channel for small molecule passage).

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Prokaryotic CellsProkaryotic CellsThe Cell Envelope: Comparison of Cell The Cell Envelope: Comparison of Cell

WallsWalls

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Prokaryotic CellsProkaryotic CellsThe Cell Envelope: The Cell Envelope:

Comparison of Gram + and Gram-Comparison of Gram + and Gram-

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The Gram Stain The Gram Stain

-> Differential stain that distinguishes cells with a Gram--> Differential stain that distinguishes cells with a Gram-positivepositive cell wall from those with a Gram-negative cell wallcell wall from those with a Gram-negative cell wall

- Gram-positiveGram-positive - retain crystal violet and stain purple - retain crystal violet and stain purple

- Gram-negativeGram-negative - lose crystal violet and stain red from - lose crystal violet and stain red from safraninsafranin counterstaincounterstain

-> Important basis of bacterial classification and identification-> Important basis of bacterial classification and identification

-> Practical aid in diagnosing infection and guiding drug -> Practical aid in diagnosing infection and guiding drug treatmenttreatment

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The Gram Stain The Gram Stain

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Atypical Cell Walls Atypical Cell Walls

Some bacterial groups lack typical cell wall structure i.e. Some bacterial groups lack typical cell wall structure i.e. Mycobacterium Mycobacterium and and NocardiaNocardia

Gram-positive cell wall structure with lipid Gram-positive cell wall structure with lipid mycolic acid mycolic acid (cord (cord factor) factor)

-> pathogenicity and high degree of resistance to certain -> pathogenicity and high degree of resistance to certain chemicalschemicals and dyesand dyes-> basis for -> basis for acid-fast stainacid-fast stain used for diagnosis of infections used for diagnosis of infections causedcaused by these microorganismsby these microorganisms

Some have no cell wall i.e. Some have no cell wall i.e. MycoplasmaMycoplasma -> cell wall is stabilized by sterols-> cell wall is stabilized by sterols-> pleomorphic (variations in shape)-> pleomorphic (variations in shape)

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Degradation of Cell Walls Degradation of Cell Walls

LysozymeLysozyme cleaves Peptidoglycan cleaves PeptidoglycanPenicillinPenicillin inhibits enzyme responsible for construction of inhibits enzyme responsible for construction of peptidoglycanpeptidoglycan

- Gram-positive Gram-positive cell exposed to one of these agents cell exposed to one of these agents -> cell wall completely loosened -> -> cell wall completely loosened -> protoplastprotoplast

- Gram-negative Gram-negative cell exposed to one of the agentscell exposed to one of the agents -> peptidoglycan loosened but outer membrane retained -> -> peptidoglycan loosened but outer membrane retained -> spheroplastspheroplast

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Cell Membrane Cell Membrane Phospholipid bilayer with embedded proteins – Phospholipid bilayer with embedded proteins – fluid mosaic modelfluid mosaic model

Functions in:Functions in:

-> providing site for energy reactions, nutrient processing, and -> providing site for energy reactions, nutrient processing, and

synthesissynthesis

-> transport into and out of the cell-> transport into and out of the cell

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Bacterial Internal Structures Bacterial Internal Structures

Cell cytoplasm:Cell cytoplasm:

-> dense gelatinous solution of sugars, amino acids, and -> dense gelatinous solution of sugars, amino acids, and saltssalts

-> 70-80% water -> 70-80% water

serves as solvent for materials used in all cell functionsserves as solvent for materials used in all cell functions

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ChromosomeChromosome

-> single, circular, double-stranded DNA molecule that-> single, circular, double-stranded DNA molecule that

contains all the genetic information required by a contains all the genetic information required by a cellcell

-> DNA is tightly coiled around a protein, aggregated in -> DNA is tightly coiled around a protein, aggregated in aa

dense area called the dense area called the nucleoid.nucleoid.

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PlasmidsPlasmids-> small circular, double-stranded DNA-> small circular, double-stranded DNA

-> free or integrated into the chromosome-> free or integrated into the chromosome

-> duplicated and passed on to offspring-> duplicated and passed on to offspring

-> not essential to bacterial growth and metabolism-> not essential to bacterial growth and metabolism

-> may encode antibiotic resistance, tolerance to toxic -> may encode antibiotic resistance, tolerance to toxic metals,metals, enzymes and toxinsenzymes and toxins

-> used in genetic engineering- readily manipulated and -> used in genetic engineering- readily manipulated and transferred from cell to celltransferred from cell to cell

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RibosomesRibosomes

-> made of 60% ribosomal RNA and 40% protein-> made of 60% ribosomal RNA and 40% protein

-> consist of two subunits: large and small-> consist of two subunits: large and small

-> procaryotic differ from eucaryotic ribosomes in size -> procaryotic differ from eucaryotic ribosomes in size andand

number of proteinsnumber of proteins

-> site of protein synthesis-> site of protein synthesis

-> present in all cells-> present in all cells

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Inclusions and granulesInclusions and granules

-> intracellular storage -> intracellular storage bodiesbodies

-> vary in size, number and -> vary in size, number and

contentcontent

-> Bacterial cell can use -> Bacterial cell can use them them

when environmental when environmental sources sources

are depleted.are depleted.

examples: glycogen, poly-b-examples: glycogen, poly-b-hydroxybutyrate, gas hydroxybutyrate, gas vesicles for floating, sulfur vesicles for floating, sulfur and phosphate granules and phosphate granules (metachromatic granules)(metachromatic granules)

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EndosporesEndospores

-> inert, resting, cells produced by some G+ genera:-> inert, resting, cells produced by some G+ genera: ClostridiumClostridium, , Bacillus and SporosarcinaBacillus and Sporosarcina

-> have a 2-phase life cycle:-> have a 2-phase life cycle:- vegetative cell – metabolically active and - vegetative cell – metabolically active and growinggrowing- endospore – when exposed to adverse endospore – when exposed to adverse environmental environmental conditions; capable of high resistance and very conditions; capable of high resistance and very long - term survivallong - term survival

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EndosporesEndosporessporulationsporulation -formation of endospores -formation of endospores

-> hardiest of all life forms-> hardiest of all life forms-> withstands extremes in heat, drying, freezing, -> withstands extremes in heat, drying, freezing, radiation andradiation and chemicals chemicals -> not a means of reproduction-> not a means of reproduction

germinationgermination- return to vegetative growth- return to vegetative growth

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Prokaryotic CellsProkaryotic CellsBacterial Internal Structures Bacterial Internal Structures

Endospores:Endospores:

-> Resistance linked to high levels of calcium and -> Resistance linked to high levels of calcium and dipicolinic aciddipicolinic acid-> Dehydrated, metabolically inactive-> Dehydrated, metabolically inactive-> thick coat-> thick coat-> Longevity verges on immortality - 25,250 million years.-> Longevity verges on immortality - 25,250 million years.-> Resistant to ordinary cleaning methods and boiling-> Resistant to ordinary cleaning methods and boiling-> Pressurized steam at 120-> Pressurized steam at 120ooC for 20-30 minutes will C for 20-30 minutes will destroydestroy

-> some pathogens make spores -> -> some pathogens make spores -> B. anthraces, C. tetaniB. anthraces, C. tetani

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Prokaryotic CellsProkaryotic CellsBacterial Shapes, Arrangements, and Bacterial Shapes, Arrangements, and

SizesSizes

Variety in shape, size, and arrangement but typically Variety in shape, size, and arrangement but typically described by one of three basic shapes:described by one of three basic shapes:

-> coccus - spherical-> coccus - spherical-> bacillus – rod-> bacillus – rod

coccobacillus – very short and plumpcoccobacillus – very short and plump vibrio – gently curvedvibrio – gently curved

-> spirillum - helical, comma, twisted rod, -> spirillum - helical, comma, twisted rod, spirochete – spring-likespirochete – spring-like

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SizesSizes

Bacterial shapes

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SizesSizes

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SizesSizes

Arrangement of cells is dependent on pattern of division and Arrangement of cells is dependent on pattern of division and how cells remain attached after division:how cells remain attached after division:

cocci:cocci:

-> singles-> singles

-> diplococci – in pairs-> diplococci – in pairs

-> tetrads – groups of four-> tetrads – groups of four

-> irregular clusters -> irregular clusters

-> chains-> chains

-> cubical packets-> cubical packets

bacilli:bacilli:

-> chains-> chains

-> palisades-> palisades

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SizesSizesArrangement of Cocci

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SizesSizesDimensions of Bacteria

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Prokaryotic CellsProkaryotic CellsClassification Systems in the ProkaryotesClassification Systems in the Prokaryotes

-> Microscopic morphology-> Microscopic morphology

-> Macroscopic morphology – colony -> Macroscopic morphology – colony appearanceappearance

-> Physiological / biochemical characteristics-> Physiological / biochemical characteristics

-> Chemical analysis-> Chemical analysis

-> Serological analysis-> Serological analysis

-> Genetic and molecular analysis-> Genetic and molecular analysis - G + C base composition- G + C base composition

- DNA analysis using genetic probes- DNA analysis using genetic probes

- Nucleic acid sequencing and rRNA analysis- Nucleic acid sequencing and rRNA analysis

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Taxonomy Based on Taxonomy Based on Bergey’s ManualBergey’s Manual

-> Bergey’s Manual of Determinative Bacteriology-> Bergey’s Manual of Determinative Bacteriology – five volume – five volume resourceresource

covering all known procaryotescovering all known procaryotes

-> classification based on genetic information –-> classification based on genetic information –phylogeneticphylogenetic

-> two domains: Archaea and Bacteria-> two domains: Archaea and Bacteria

-> five major subgroups with 25 different phyla-> five major subgroups with 25 different phyla

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Major Taxonomic groups:Major Taxonomic groups:

Domain Archaea – Domain Archaea – primitive, adapted to extreme primitive, adapted to extreme habitats and modes of nutritionhabitats and modes of nutrition

Domain BacteriaDomain Bacteria – – Phylum ProteobacteriaPhylum Proteobacteria – Gram-negative cell walls – Gram-negative cell wallsPhylum FirmicutesPhylum Firmicutes – mainly Gram-positive with low G + C – mainly Gram-positive with low G + C content content Phylum ActinobacteriaPhylum Actinobacteria – Gram-positive with high G + C – Gram-positive with high G + C contentcontent

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Diagnostic Scheme for Medical Use:Diagnostic Scheme for Medical Use:

Uses phenotypic qualities in identificationUses phenotypic qualities in identification

-> restricted to bacterial disease agents-> restricted to bacterial disease agents

-> divides based on cell wall structure, shape, -> divides based on cell wall structure, shape, arrangement,arrangement,

and physiological traitsand physiological traits

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Gram-positive Pathogens

Bacillus anthracis Clostridium botulinum. CDC.C. tetaniC. tetani -> tetanus -> tetanus

Staphylococcus aureus Corynebacterium diphtheriae

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Gram-negative Pathogens

Neisseria meningitis

Yersinia pestis

B. Burgdorferi

Borrellia -> Lyme disease

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Pathogen with no cell wall

Mycoplasma “fungus-form”Mycoplasma “fungus-form”

-> pneumonia-> pneumoniaThe smallest bacteria - 0.2 micrometersThe smallest bacteria - 0.2 micrometers

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The smallest Bacteria – Nanobes or Nanobacteria

-> Size: 0.05 – 0.2 μm-> first isolated in blood serum-> grow in cultures-> have cell walls, protein, nucleic acids-> isolated from sandstone from ocean (100-170°, embedded in minerals)

Not clear if:

-> they are similar to first microbe on earth-> or just artifacts, part of cells since functional cells need to be at least 0.13μm

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Species and Subspecies in Bacteria

SpeciesSpecies –a collection of bacterial cells which share an overall –a collection of bacterial cells which share an overall similar pattern of traits in contrast to other bacteria whose similar pattern of traits in contrast to other bacteria whose pattern differs significantly pattern differs significantly

StrainStrain or or varietyvariety – microbes that belong to the same species – microbes that belong to the same species but are further subdivided based on unique chemicals found but are further subdivided based on unique chemicals found either on the cell surface, or being secreted as exotoxins. For either on the cell surface, or being secreted as exotoxins. For example, there is a difference between the type of toxin example, there is a difference between the type of toxin produced by the strain of produced by the strain of E.coliE.coli in the U.S., and the strain found in the U.S., and the strain found in water in Mexicoin water in Mexico

TypeType – a subspecies that can show differences in antigenic – a subspecies that can show differences in antigenic makeup (serotype or serovar), susceptibility to bacterial viruses makeup (serotype or serovar), susceptibility to bacterial viruses (phage type) and in pathogenicity (pathotype)(phage type) and in pathogenicity (pathotype)

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Prokaryotes with unusual characteristics

Cyanobacteria (blue-green Cyanobacteria (blue-green algae)algae)

Photosynthetic bacteria - use Photosynthetic bacteria - use photosynthesis, can photosynthesis, can synthesize required nutrients synthesize required nutrients from inorganic compoundsfrom inorganic compounds

Formed OFormed O22 in the earth’s in the earth’s atmosphereatmosphere

Gram-negative cell wallsGram-negative cell walls

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Prokaryotes with unusual characteristics

Green and purple sulfur bacteriaGreen and purple sulfur bacteria

contain photosynthetic pigment contain photosynthetic pigment bacteriochlorophyllbacteriochlorophylldo not give off oxygen as a product of photosynthesisdo not give off oxygen as a product of photosynthesisLive in sulfur springs Live in sulfur springs

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Prokaryotes with unusual characteristics - Pathogens

RickettsiasRickettsias

Very tiny, Gram-negative bacteriaVery tiny, Gram-negative bacteriaMost are pathogens that alternate between mammals and Most are pathogens that alternate between mammals and fleas, lice or ticks.fleas, lice or ticks.Rickettsia rickettisiiRickettsia rickettisii – Rocky Mountain spotted fever – Rocky Mountain spotted feverRickettsia prowazekiiRickettsia prowazekii – epidemic typhus – epidemic typhusCoxiella burnettiCoxiella burnetti – Q fever – Q fever

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Prokaryotes with unusual characteristics - Pathogens

ChlamydiasChlamydias

TinyTiny

Chlamydia trachomatisChlamydia trachomatis – – severe eye infection and one of severe eye infection and one of the most common sexually the most common sexually transmitted diseasestransmitted diseases

Chlamydia psittaciChlamydia psittaci – ornithosis, – ornithosis, parrot feverparrot fever

Chlamydia pneumoniaeChlamydia pneumoniae – lung – lung infectionsinfections

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Prokaryotic CellsProkaryotic CellsArchaeaArchaea

-> Constitute third Domain Archaea-> Constitute third Domain Archaea

-> Seem more closely related to Domain Eukarya than to -> Seem more closely related to Domain Eukarya than to bacteriabacteria

-> Have unique membrane lipids (ether lipids) and cell wall -> Have unique membrane lipids (ether lipids) and cell wall constructionconstruction

-> Live in the most extreme habitats in nature, extremophiles-> Live in the most extreme habitats in nature, extremophiles

-> Adapted to heat, salt, acid pH, pressure and atmosphere-> Adapted to heat, salt, acid pH, pressure and atmosphere

Includes: methane producers, hyperthermophiles, extreme Includes: methane producers, hyperthermophiles, extreme halophiles, and sulfur reducershalophiles, and sulfur reducers

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Prokaryotic CellsProkaryotic CellsArchaeaArchaea

Thermophiles growing in

Yellowstone hot springs.

Thermophiles growing in

Yellowstone hot springs. Halophiles growing in Owens

Lake, California.

Halophiles growing in Owens

Lake, California.

1 Applied Microbiology 3 nd lecture: Chapter 4. 2 Prokaryotic Cells Characteristics of Cells and...

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Transcript of 1 Applied Microbiology 3 nd lecture: Chapter 4. 2 Prokaryotic Cells Characteristics of Cells and...