THE MICROBIAL WORLD:

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THE MICROBIAL WORLD MONERA BACTERIA
ARCHAEOBACTERIA PROTISTA UNICELLULAR OR
COLONIAL EUCARYOTES THAT LACK TRUE
TISSUE. FUNGI EUKARYOTIC ORGANISMS WITH
ABSORPTIVE NUTRITION OFTEN MULTI-CELLULAR. ANIM
ALIA PLANTAE ARE NOT STUDIED BY THE
MICROBIOLOGIST. VIRUSES ACELLULAR/
NON-LIVING
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SIZE, SHAPE ARRANGEMENT OF PROCARYOTIC
CELL BACTERIA VARY IN THEIR SIZE FROM
MYCOPLASMA (LACK CELL WALLS AND ARE THE SMALLEST
ORGANISMS CAPABLE OF INDEPENDENT REPRODUCTION) TO
THOSE APPROX. THE SIZE OF THE LARGEST VIRUS (POX
VIRUS).
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SIZE, SHAPE ARRANGEMENT OF PROCARYOTIC
CELLS BACTERIA (PROCARYOTES) COME IN A VARIETY OF
SHAPE SPHERES (COCCI), RODS (BACILLI),
CURVED RODS (VIBRIOS), RIGID HELICES
(SPIRILLA), FLEXIBLE HELICES (SPIROCHETES),
LACKING A SPECIFIC CHARACTERISTIC FORM
VARIABLE SHAPE (PLEOMORPHIC, E.G.,
CORYNEBACTERIUM).
Streptobacillus
Bacillus w/spore Tetanus bacillus
Club-shaped bacillus diphtheria
Bacillus anthrax
Streptococcus
Diplococcus S. pneumoniae
Diplococcus gonorrhea
Sarcinae/packet of 8 Cube-like
Spirocheted Rigid/ no flagella
Vibrio, e.g., cholera
Spirilla, Rigid flagella
staphylococcus
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SIZE, SHAPE ARRANGEMENT OF PROCARYOTIC
CELL ARRANGEMENT BY REMAINING ATTACHED AFTER
REPRODUCTION BACTERIA MAY HAVE CHARACTERISTIC
ARRANGEMENTS CHAINS (E.G., STREPTOCOCCUS)
CLUSTERS (E.G., STAPHYLOCOCCUS) SQUARE PLANAR
CONFIGURATION (TETRADS) CUBIC, PACKAGES OF
EIGHT CELLS, CONFIGURATION (SARCINAE).
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE TO
OBSERVE BACTERIA, THEY MUST BE STAINED STAINING
FIXATION PRESERVE FINE STRUCTURE OF
ORGANISMS. FIXATIES INCLUDE HEAT OR CHEMICALS
(ETHANOL, GLUTERALDEHYDE, MERCURIC ACIDS)
FIXATIVES BIND TO MACROMOLECULES TO RENDER THEM
INSOLUBLE, INACTIVE IMMOBILE. STAINS ACIDIC
HAVE IONIZING GROUPS (COOH) NEGATIVE CHARGES
BIND TO POSITIVELY CHARGED CELL
STRUCTURES. BASIC HAVE POSITIVE CHARGES BIND
TO NEGATIVELY CHARGED GROUPS ON CELL STRUCTURES.
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE OBSERVATION OF BACTERIA REQUIRE
SEVERAL STAINING TECHNIQUES SIMPLE STAINING
TECHNIQUES SINGLE DYE TO ENHANCE THE CONTRAST OF
THE SPECIMEN AGAINST THE BACKGROUND. DIFFERENTIAL
STAINING DIVIDES BACTERIA INTO DIFFERENT GROUPS
BASED ON STAINING PROPERTIES, e.g., GRAM
STAINING ACID FAST STAINING SPECIAL STAINING
TECHNIQUES STAINING FOR SPECIFIC STRUCTURES.
STAINS HAVE AFFINITY FOR CELL STRUCTURES THEY
HIGHLIGHT STRUCTURES AS STAINED COMPONENTS
(POSITIVE STAINS) ENDOSPORE STAINING GRANULE
STAINING VS. NEGATIVE STAINING - CELLS ARE
LIGHT AGAINST A DARK BACK- GROUND (E.G., STAIN
WITH INDIA INK) - CAPSULE STAINING FLAGELLA
STAINING
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PROCARYOTIC CELL ORGANIZATION STRUCTURE

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PROCARYOTIC CELL ORGANIZATION
STRUCTURE NEGATIVE STAINING TO OBSERVE CAPSULE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE THE
CYTOPLASMIC MEMBRANE IS MADE UP OF AMPHIPATHIC
LIPIDS IN A BILAYER AND IS SIMILAR TO THAT OF THE
EUCARYOTIC CELL. IT IS A SELECTIVELY PERMEABLE
MEMBRANE LOCATION OF METABOLIC ENZYMES
TRANSPORT PROTEINS SITE OF RESPIRATION LIPID
SYNTHESIS AND PHOTOSYNTHESIS PROTEINS THAT
ALLOW CELLS TO DETECT AND RESPOND TO CHEMICALS
RESIDE IN THE MEMBRANE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE CELL
ENVELOPE OUTER COVERING OF PROCARYOTES MADE
UP OF PLASMA MEMBRANE CELL WALL OUTER
MEMBRANES (GRAM NEGATIVES) PLASMA MEMBRANE -
SELECTIVELY PERMEABLE BARRIER - PROVIDES
STRUCTURAL INTEGRITY TO BACTERIA LACKING CELL
WALL (E.G., MYCOPLASMA) - SIMILAR IN COMPOSITION
TO EUCARYOTIC MEMBRANE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
AMPHIPATHIC MOL HYDROPHILIC POLAR GROUP
HYDROPHOBIC NON-POLAR CHAIN
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PROCARYOTIC CELL ORGANIZATION STRUCTURE CELL
WALL MAINTAINS CELL SHAPE AND CONFORMATION -
RIGID, COMPLEX INFLEXIBLE LYER EXTERNAL TO CELL
MEMBRANE - ENABLES CELLS TO SURVIVE IN HYPOTONIC
ENVIRONMENTS - CELLS LACKING CELL WALL
(MYCOPLASMA) COMPENSATE WITH STEROL CONTAINING
PLASMA MEMBRANES - CELL WALLS ARE NOT UNIQUE TO
BACTERIA (PLANTS CELLULOSE FUNGiCHITIN).
BACTERI CELL WALL MADE UP OF POLYSACCHARIDE
CALLED PEPTIDOGLYCAN OR MUREIN - ONE TO
SEVERAL LAYERS THICK - MADE UP OF
REPEATING UNITS OF TWO CARBOHYDRATE
DERIVATIVES N-ACETYLGLUCOSAMINE
(NAG) N-ACETYLMURAMIC ACID (NAM) - FOUND NOWHER
ELSE IN NATURE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
B(1,4)
FOUR AMINO ACIDS MAKE UP WHAT IS CALLED A
TETRAPEPTIDE, ATTACHED TO THE NAM. MOST GRAM
POSITIVES COCCI HAVE SIMILAR TETRAPEPTIDE EXCEPT
DAP IS REPLACED BY L-LYSINE TETRAPEPTIDE MAY BE
FURTHER MODIFIED IN OTHER BACTERIA
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
MAJOR STRENGTH OF CELL WALL COMES FROM PERIODIC
CROSS LINKINGBETWEEN THE THIRD FOURTH AA ON
ADJACENT TETRAPEPTIDE CROSS-LINKING MAY BE
EITHER DIRECTLY (AS IN MOST GM NEGATIVE CELLS) OR
VIA A PENTA-GLYCINE LINK (AS IN MANY GM POSITIVE
CELLS)
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE
CROSS-LINKING MAY BE EITHER DIRECTLY (AS IN MOST
GM NEGATIVE CELLS) OR VIA A PENTA-GLYCINE LINK
(AS IN MANY GM POSITIVE CELLS) NOT ALL
PROKARYOTES HAVE PEPTIDO- GLYCAN IN THEIR CELL
WALLS ARCHAEA INSTEAD HAVE CELL WALLS COMPOSED
OF POLYSACCHARIDES, GLYCOPROTEINS PROTEINS.
THEY DO NOT HAVE NAM IN THEIR WALLS
MYCOPLASMA, WITH NO CELL WALLS, HAVE CELL
MEMBRANES WITH STEROLS TO PROVIDE STRENGTH
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
IN GM POSITIVES PEPTIDOGLYCAN MAY BE AS MUCH AS
40 LAYERS THICK MOST OF THE CELL WALL (90) MAY
BE MADE UP OF PEPTIDOGLYCAN, BUT THE REMAINDER
MAY BE OF ACIDIC POLYSACCHARIDE CALLED TEICHOIC
ACID (THEY ARE NEGATIVELY CHARGED MOLECULES)
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
GM NEGATIVES HAVE THINNER CELL WALLS (A FEW
LAYERS THICK AND APROX. 5- 20 OF ENVELOPE).
INSTEAD THEY HAVE AN OUTER MEMBRANE STRUCTURE
SIMILAR TO THE CELL MEMBRANE, BUT THE
COMPOSITION IS SLIGHTLY DIFFERENT
LIPOPOLYSACCHARIDE (LPS) MAKE UP ABOUT 40 OF THE
OUTER LIPID BI-LAYER.
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
O-SIDE CHAIN
CORE- POLYSACCHARIDE
LIPID A
O SIDE CHAIN VARIES DEPENDING ON THE
BACTERIUM CORE POLYSACCHARIDE RELATIVELY
CONSTANT COMPOSITION LIPID A COMPOSED OF
GLYCOLIPIDS ASSOCIATED WITH TOXIC ACTIVITY IN
GRAM-NEGATIVE BCTERIUM
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE CELL
WALL OF THE ACID-FAST BACTERIA
THICK WALL LIKE THAT OF GM POSIIVES. PEPTIDOGLYCA
N IS LESS ABOUT 60 LIPID. THE LIPID MAKES
THE BACTERIA IMPERMEABLE TO MOST STAINS AND
PROTECTS IT FROM ACIDS AND ALKALIS CARBOLFUCHSIN
BINDS CYTOPLASM RESIST ACID- ALCOHOL
DESTAINING. SLOW GROWTH OF BACTERIA DUE TO
INEFFICIENT ENTRY OF NUTRIENTS INTO THE CELL
LARGE AMOUNTS OF ENERGY MUST BE EXPENDED TO TAKE
UP NUTRIENTS.
MYCOBACTERIA
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PROCARYOTIC CELL ORGANIZATION STRUCTURE THE
IMPORTANCE OF CELL ENVELOPES IN PRESERVING THE
STRUCTURAL INTEGTITY OF BACTERIA IS ILLUSTRATED
THROUGH THE LABORATORY CONSTRUCTS PROTOPLASTS
SPHEROPLAST (CELLS WITHOUT MUREIN). PROTOPLAST
GRAM POSITIVE CELLS WITHOUT MUREIN SPHEROPLAST
GRAMNEGATIVE CELLS WITHOUT MUREIN (RETAIN OUTER
MEMBRANE) LYSOZYME OR PENICILLIN USED TO CREATE
THESE CELLS. THEY SURVIVE ONLY IN ISOTONIC
SOLUTIONS
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PROCARYOTIC CELL ORGANIZATION STRUCTURE THE
CELL WALL OF THE ARCHAEA THE PROCARYOTES SURVIVE
IN EXTREME ENVIRONMENTS (HIGH SALT, TEMPERATURES,
AND pH EXTREMES) CONSIST OF BOTH GRAM POSITIVE
AND GRAM NEGATIVE CELLS - THEY DO NOT HAVE
MURAMIC ACID OR D-AMINO ACIDS. - SOME
ARCHAE HAVE A MOLECULE CALLED PSEUDOPEPTIDOGLYCAN
(REPEATING UNITS OF NAG AND N- ACETYLTALOSAMINURON
IC ACID AND L-AMINO ACIDS (NOT THE D-AMINOACIDS
FOUND IN TRADITIONAL PEPTIDOGLYCAN). - OTHERS
HAVE SURFACE MONOLAYER OF PROTEINS OR
GLYCOPROTEINS LACK PSEUDOMUREIN. -OTHERS
HAVE NO WALLS CYTOPLASMIC MEMBRANE IS THE ONLY
CONSTITUENT OF THE ENVELOPE -BETWEEN THE
ALTERNATING CARBOHYDRATES IS BETA(1,3) NOT
BETA(1,4) OF PEPTIDOGLYCAN AND IT IS RESISTAN TO
LYSOZYME.
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE PERIPLASMIC SPACE GAP BETWEEN PLASMA
MEMBRANE AND THE CELL WALL. MOST EASILY OBSERVED
IN GM-NEGATIVES. LESS DEFINED IN GM-
POSITIVES ACTIVE AREA OF CELL METABOLISM WITH
HYDROLYTIC ENZYMES, TRANSPORT PROTEINS AND CELL
WALL BUILDING BLOCKS.
NOTE DIFFERENCES IN THE SIZE OF THE PERIPLASMIC
SPACE
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PROCARYOTIC CELL ORGANIZATION
STRUCTURE GLYCOCALYX REFERS TO ALL
POLYSACCHARIDE-CONTAINING SUBSTANCES FOUND
OUTSIDE THE CELL WALL (I.E., CAPSULE OR SLIME
LAYER OR GLYCOCALYX) THE CAPSULE EXTERNAL TO THE
ENVELOPE PRESENT IN SOME BACTERIA (NOT ALL
MEMBERS OF A SPECIES MAY HAVE CAPSULES) A LOOSE
GEL, COMPOSED OF POLYSACCHARIDE, PROTEIN, OR ONLY
GLYCOPROTEINS PROTECTS CELL FROM DESSICATION,
NUTRIENT LOSS AND PHAGOCYTOSIS MAY BE VISUALIZED
BY QUELLUNG RXN (SPECIFIC ANTIBODIES BIND TO
CAPSULE INCREASE REFRACTIVITY CAPSULE APPEARS
SWOLEN) SLIME LAYER (GLYCOCALYX) THINNER THAN
CAPSULE, AND WHEN PRESENT PREVENTS CELLS FROM
DRYING OUT TRAPS NUTRIENT. POLYSACCHARIDE
ARRANGESD AS FIBROUS MATRIX ALSO ALLOWS BACTERIA
TO ADHERE TO EACH OTHER AND OTHER OBJECTS (EG.,
BACTERIA IN DENTAL PLAQUE ON TOOTH SURFACE)
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PROCARYOTIC CELL ORGANIZATION STRUCTURE
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PROCARYOTIC CELL ORGANIZATION STRUCTURE OTHER
EXTERNAL STRUCTURES FLAGELLA RESPONSIBLE FOR
MOTILITY USED IN CHEMOTAXIS (MOVEMENT TO OR AWAY
FROM SUBSTANCES IN THEIR ENVIRONMENT) OR
PHOTOTAXIS MAY BE ARRANGED DIFFERENTLY DEPENDING
ON SPECIES
SINGLE FLAGELLUM MONOTRICHOUS ONE FLAGELLUM AT
EACH POLE AMPHITRICHOUS TWO OR MORE FLAGELLA
AT ONE OR BOTH POLES LOPHOTRICHOUS FLAGELLA
ALL OVER THE SURFACE PERITRICHOUS
AMPHITRICHOUS
MONOTRICHOUS
PERITRICHOUS
LOPHOTRICHOUS
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PROCARYOTIC CELL ORGANIZATION STRUCTURE FIMBRIA
PILI (SOMETIMES USED INTERCHANGBLY) FIMBRIA -
SHORTER AND STRAIGHTER THAN FLAGELLUM - FIMRAE
MAY BE EVENLY DISTRIBUTED OVER ENTIRE SURFACE
USED FOR ATTACHMENT (EG., NEISSERIA GONORRHOEA
USE THEM TO ATTACH TO MUCOU MEMBRANES AND CAUSE
DISEASE) PILI - USUALLY LONGER THAN FIMBRIAE
NUMBER ONLY 1 OR 2/CELL - USUALLY USED IN DNA
TRANSFER DURING CONJUGATION