Basic Concepts In Microbiology PDF

BASIC CONCEPTS MLSBACTC CLINICAL IN MICROBIOLOGY....

BASIC CONCEPTS MLSBACTC CLINICAL IN MICROBIOLOGY. BACTERIOLOGY [LEC] CONTENTS  mitochondria  endoplasmic reticulum Microbiology  golgi apparatus o Bacteria………………………...………….….1 - cell walls composed of peptidoglycan o Archea………………… ………………..…...1 layer L diff. from plants o Fungi……………………………………....….1 - Bacteriology – study of bacteria o Protozoan………………………...…..…..….2 o Helminths..…………… ………………..…...2 o Virus……………………………………....….2 o Subdisciplines………………...………….….2 o Bacterial Taxonomy… ………………..…....3 o Hooke………………………………….....….3 o Leeuwenhoek.……… ………………..…....3 o Pasteur……………….………………....…...4 o Koch………………...……………..…….…..5 o Other contributor…… ………………..…....5 Microorganism ARCHEA o Roles………………………………..……….5 - prokaryotic cells that may or may not o Pathogenecity…………..…...……………..5 have cell walls ( w/ cell walls – no o Normal flora…………….…….…….…..…..5 o Biofilms……..…………..…...………….…..5 peptidoglycan) o Infection…..…………….…….…….…..…..6 - in extreme environments - not known to cause disease MICROBIOLOGY Examples - scientific study of microorganisms Prokaryotes Eukaryotes 1) Methanogens – methane as waste Microorganisms true nucleus + true nucleus - nuclear mem membrane bond organelles product salt loving - known as germs and microbes 2) Extreme halophiles – in extreme salty - minute organisms that are individually environments too small to be seen with the naked 3) Extreme thermophiles – in hot, eye sulfurous water such as hot spring - single cell or cell clusters  bacteria  fungi (mold and yeasts)  protozoa  algae  virus (non-cellular entities straddling between life and non- life) FUNGI Mushrooms-plant like fungi BACTERIA - eukaryotes obtain nutrients through - prokaryotes absorption ~ same as bacteria - unicellular organisms that lack a 1) Yeast – group of unicellular fungi that nuclear membrane and true nucleus reproduce asexually through budding ~ - lack membrane-bound organelles such - do not form hyphae and mycelia as: 1 Psalm 56:3 When I am afraid, I put my trust in you. Protozoans. MLSBACTC CLINICAL BACTERIOLOGY [LEC] cottony appearance ~ 2) Molds – multicellular fungi composed  flatworms (cestodes and of filaments called hyphae w/c trematodes) interweaves to form mats called - Helminthology – study of helminths mycelia - reproduce asexually or sexually 3) Dimorphic fungi – assume both morphologies Spanogenic  Yeast – incubator or human temp will be yealt for inside ~  Mold – room temp - causative agents of systemic infection to a tem o VIRUS ~ electron microscope mycoses are dimorphic - Mycology – study of fungi - smallest infectious particle that can’t be seen under an ordinary light microscope - neither prokaryotic or eukaryotic and are distinguished from living cells with hyphae the ff. characteristics 1) Consists of either DNA or RNA, but not both -doublerandedsingletranded 2) Genome may be dsDNA, ssDNA, dsRNA, ssRNA PROTOZOANS 3) Acellular required cell smaller than cell affect ~ no , survive host to ~ ~ 4) Obligate intracellular parasites - unicellular eukaryotic microorganism 5) Host- or host cell specific ~ particular to host that move by pseudopods, flagella, or - Virology - study of viruses Host cell specific & cilia Barr Virus (kissing Epstein - free living or parasitic 1 particular to B Cells - asexually or sexually Human Immuno virus L CD4 molecules - Protozoology – study of protozoans It. helper , macro phages) SUBDISCIPLINES OF MICROBIOLOGY Focus : lab identification Focus : prevention Focus : Treatment HELMINTHS - not strictly microorganisms (multicellular parasitic eukaryotes) Pathogens [ - microscopic in some stages of their life known to cause human cycle disease OTHER DISCIPLINES RELATED  roundworms (nematodes) 1) Immunology – study of immunity 2 Psalm 56:3 When I am afraid, I put my trust in you.  Taxonomy. MLSBACTC CLINICAL BACTERIOLOGY [LEC] 2) Microbiology genetics – studies the bacterial species into family, genus, mechanisms by which microorganisms species inherit traits 3) Molecular biology – looks at how genetic information is carried in molecules of DNA and how DNA directs the synthesis of proteins 4) Microbial ecology – study of the Family 8 [ relationship between microorganisms and their environment First name ~ Bloody - diarrhea BACTERIAL TAXONOMY mostrient NOMENCLATURE · VI - from greek word “taxon” – arrangement - naming assignment to each organism - classification of organisms in an - Capitalize and “-aceae” – family ordered system that indicates a natural name relationship  Enterobacteriaceae - Capital (genus) lowercase (species Three separate but interrelated areas in epithet) bacterial taxonomy caracteristic based on  Print: Escherichia coli ~ 1) Classification - categorization of  Written: Escherichia coli [ organisms into taxonomic groups - sp. – singular (based on biochemical, physiologic, - spp. – plural genetic, and morphologic properties)  Staphylococcus spp. 2) Nomenclature – naming of an ROBERT HOOKE (1665) termed cells organism by international rules according to its characteristics - “cells” or “little boxes” after observing a 3) Identification – practical use of a thin slice of cork through a crude classification scheme to: microscope  Isolate and distinguish - Cell theory – all living things are desirable organisms from composed of cells undesirable ones - lacked the resolution that would have  Verify the authenticity or allowed him to view microbes clearly special properties of a culture ANTON VAN LEEUWENHOEK (1673-1723) in a clinical setting ↑ first discovered ↑  Isolate and identify the - Animalcules - live microorganisms causative agent of a disease - detailed drawings of microorganisms he found in rainwater, feces, and TAXONOMIC RANKS materials he scraped from teeth - form the basis for the organization of bacteria - Linnaean taxonomy – most familiar to biologist - diagnostic microbiologist traditionally emphasize placement and naming of 3 Psalm 56:3 When I am afraid, I put my trust in you.  Pasteur. MLSBACTC CLINICAL BACTERIOLOGY [LEC] SPONTANEOUS GENERATION THEORY - stating that some forms of life could arise spontaneously from non-living LOUIS PASTEUR (1861) matter - even before this, people commonly - microbes can be in non-living matter believed that animals could be born of - can be destroyed by heat moist soils, flies from manure, and - methods can be devised to block the maggots from decaying corpses access of airborne microbes to nutrient environments (became the basis for aseptic techniques) swar nument maggots arise & doesno e 4 arie ~ produceono - Fermentation – anaerobic decomposition of carbohydrate - Pasteurization – process in w/c foods are treated w/ mild heat ( bacillus colon pathogenic but act as a pathogen E coli in S I. will cause Diarrhea under certain circumstances. in Urethra UT E Coli. common : Female) c) Pathogenic – causing disease to the dysenteriae Salmonella enterica host ↳ dysentery shigella (typhi Typhoid > fever ↓ If parasite : histolytica NORMAL FLORA OTHER SIGIFICANT CONTRIBUTORS father of immunology ~ - normally found in and on the body 1) Edward Jenner – smallpox vaccine - do not cause harm under normal 2) Rudolf Virchow – challenged conditions spontaneous generation theory with - benefits host by preventing overgrowth the concept of biogenesis of pathogenic microbes and by 3) Ignaz Semmelweis – physicians who Father of S producing certain vitamins such as vit handwalking didn’t wash their hands routinely ~pregnant K and some B vitamins transmitted puerperal fever from one - ↳> streptococcus - growth of these microorganisms are patient to another pyogenes kept in check by the immune system 4) Joseph Lister – surgery under aseptic conditions using phenol BIOFILMS in soliderface (sticks 5) Paul Ehrlich – salvarsan (arsenic- derived drug against syphilis) - complex aggregation of m 6) Alexander Fleming – penicillin microorganisms on solid surfaces (antibiotic N produced by Penicillium - beneficial effects – protects mucous atum) (no + chrysogenum) membranes from harmful 2 Fungi microorganism MICROORGANISMS AND HUMAN - harmful effects – contaminate med DISEASES implants such as joint prostheses and catheters and cause infection ROLES OF MICROORGANISMS 1) Part of the food chain very important in Ecosystem 5 Psalm 56:3 When I am afraid, I put my trust in you.  Infections. MLSBACTC CLINICAL BACTERIOLOGY [LEC] INFECTION AND INFECTIOUS DISEASE microorganism is the and enters body 1) INFECTION - not part of normal flora - invasion or colonization of the body by disease causing microorganisms - an infection may exist in the absence virus does not cause of the disease cause damage damage = - HIV vs AIDS ~ body to the 2) INFECTIOUS DISEASE - disease in which pathogens invade a susceptible host - pathogen carries out a part of its cycle which causes disease known outbreak, Re emerging ~ 3) EMERGING INFECTIOUS DISEASE emerged before , controlled re-emerged S and then - infectious disease that are new or disease is not known changing and are increasing or have before the potential to increase in incidence in the future  COVID 19  MERS  SARS - Zayed to continued byirus Savemutation  AVIAN FLU bird flu Coonotic 3 (influenca) ~  SWINE FLU pig ~ 6 Psalm 56:3 When I am afraid, I put my trust in you. BACTERIAL CELL MLSBACTC CLINICAL BACTERIOLOGY MORPHOLOGY AND PHYSIOLOGY. [LEC] CONTENTS processes than If cell wall is present, mitosis they are chemically Prokaryotic and Eukaryotic cells simple o Size range..…………………...………….….1 o Shape………………… ………………..…...1 Multiply through mitosis Bacterial Cell Structures o Glycocalyx…………………………..……….3 o Flagellum…….…………..…...……………..3 SIZE RANGE o Axial filament..………….…….…….…..…..4 o Fimbriae and Pili...……..…...………….…..4 o Cell wall.…..…………….…….…….…..…..5 o Acid fast cell wall…………………..……….6 o Plasma membrane……..…...……………..6 o Cytoplasm...…………….…….…….…..….6 o Nucleoid..…..…………..…...………….…..7 o Ribosomes.…………….…….…….…..…..7 o Inclusions...…………….…….…….…..…..7 o Endospores...…………..…...………….….8 PROKARYOTIC AND EUKARYOTIC I. mm-human eye SHAPE I. COCCUS - plural: cocci - spherical, round, oval 1) Diplococci – in pairs 2 PROKARYOTIC EUKARYOTIC 2) Tetrads – divides in 2 planes and DNA – in nucleus remain in groups of 4 DNA – not enclosed (separated from 3) Sarcinae – divides into 3 planes and in nuclear cytoplasm by a remain in cube like groups of eight membrane – nuclear membrane) 4) Streptococci – in chains singular Found in multiple 5) Staphylococci – divides in multiple Circularly arranged chromosome and planes and form grape-like clusters or chromosome and consistently broad sheets not associated w/ associated w/ Irregular cluster histones histones Lack of membrane Membrane-closed bound organelles organelles mitochondria Peptidoglycan cell Endoplasmic walls reticulum golgi Multiply by binary apparatus fission – fewer lysosomes structures and 1 Psalm 56:3 When I am afraid, I put my trust in you.  Bacillus. Neisseria gonorrnae MLSBACTC CLINICAL BACTERIOLOGY [LEC] Gonorrhea T chinese letter chain strepcocus pyogenes aureus part of normal flora Staphylococcus II. BACILLUS - plural: bacilli - rod-shape 1) Diplobacilli – in pairs after division 2) Streptobacilli – in chains 3) Coccobacilli – oval appearance Ismaller than common bacteria 2 Psalm 56:3 When I am afraid, I put my trust in you.  Spiral. MLSBACTC CLINICAL BACTERIOLOGY [LEC] III. SPIRAL - Slime layer – unorganized, loosely - one or more twists attached glycocalyx 1) Spirillum - Capsule – organized and firmly - - plural: spirilla helical shape like corkscrew and ( attached glycocalyx stronger, - virulence factor – protects bacteria moves by flagella S from phagocytosis by the host cell helps in causing 2) Spirochete disease , evading phagocytes not all bacteria - helical and flexible that moves by axial has prominent Endotiagena filaments capsule colled Visualize through dark field microscope D F microscope. ~ Exeptospira inerran is S. E m streptococcus pneumoniae FLAGELLUM - long filamentous appendages that BACTERIAL CELL STRUCTURES propel bacteria, allowing bacterium to move towards favorable envi or away from adverse ones Types 1) Atrichous – no flagellum non motile 2) Peritrichous – flagella are distributed over the entire cell Ex E coli ·. 3) Monotrichous – single flagellum at one pole Ex vibrio cholerae - 4) Lophotrichous – tuft of flagella at one pole 5) Amphitrichous – flagella at both GLYCOCALYX ~ Outermost part poles of the cell Peritrichous - viscous, gelatinous polymer that is external to the cell wall and composed of polysaccharide polypeptide both - made inside the cell and secreted to the cell surface layer of bacterial cell organized in upper 3 Psalm 56:3 When I am afraid, I put my trust in you.  Flagellum. MLSBACTC CLINICAL BACTERIOLOGY [LEC] motile Pseudomonas uly E Coli Vibrio cholerae aeruginosa 1) Run/Swim – move in one direction for. Hig W O a length of time 2) Tumble – periodic; abrupt, random one pole changes in direction side OI - due to reversal or flagellar rotation 3) Swarm – rapid wavelike movement across a solid media - due to multiple flagella Rotational motion Parts of flagellum ~ 1) Filament – the long, outermost region, constant in diameter and contains flagellin 2) Flagellin – globular proteins arranged AXIAL FILAMENT in several chains that intertwine and I also known form a helix around a hollow core - endoflagella 3) Hook – slightly wider attachment of - fibril bundles arising at the end of the filament that is composed of a different cell beneath an outer sheath and spiral protein around the cell 4) Basal body – anchors the flagellum to - used by spirochetes for motility the cell wall and the plasma - rotation of filaments produces a 2 basal body I pair membrane Gram + ,> movement of the outer sheath that - Gram--> 4 basal body , < pairs Outer cell membrane propels the spirochete in a spiral 12 cell membrane) motion corkscrew motion due to vibration for movement - prokaryotic flagellum moves the cell by FIMBRIAE AND PILI ~ anchor , virulence factor rotating from basal body (either - hair like, appendages that are shorter, clockwise or counterclockwise) straighter, and thinner than flagella Basic motility patterns 1) Fimbriae 4 Psalm 56:3 When I am afraid, I put my trust in you.  Cell wall. MLSBACTC CLINICAL BACTERIOLOGY [LEC] - singular: fimbria - tendency to adhere to each other and to surfaces – involved in forming biofilms and other aggregations on called surface such as epithelial surface also pili set ~for = 2) Pili conjugation transfer of information - singular: pilus Lbacterial genetic - longer than fimbriae and are only 1-2 per cell - involved in motility and DNA transfer - composed of peptidoglycan (murein) layers S composed of peptide chains Components and. carb monomer 1) N-acetylglucosamine 2) N-acetylmuramic acid 3) Polypeptides creates a chain the entire cell /forming wall of bacteria Polypeptide CELL WALL ~ one of most important, differentiating bacteria - complex, semirigid structure that is GRAM POSITIVE GRAM NEGATIVE violet color-due to thick layer of peptidoglycan responsible for the shape of the cell Thick layer of Thin peptidoglycan - surrounds underlying cell membrane peptidoglycan and layer and protect the cell from adverse teichoic acid (wall changes in the environment teichoic acid) Peptidoglycan is Major functions bonded to Plasmic space – lipoproteins in outer 1) Prevents cell rupture when H2O between cell well membrane pressure is greater inside than outside and cell membrane (periplasm) 2) maintain cell shape - contains 3) anchorage for flagella lipoteichoic Do not contain Ho ok of bacteria acid teichoic acid – more susceptible to is attached mechanical breakage colors (purple Gram staining violet ~ crystal stain Primary · mordant - gramsdina no 5 · reddish color) Psalm 56:3 When I am afraid, I put my trust in you. decolorizer · · (pink , Counterstain-Safranin Gram negative  Acid-fast. - Phospholipid bilayer – polar head MLSBACTC CLINICAL BACTERIOLOGY [LEC] Outer membrane (phosphate group and glycerol) and LPS non-polar tails (fatty acids) LPP phospholipids porins thick cell wall 7 Scelmembrane Protein molecules one side ~ 1) Peripheral proteins – in inner or outer space and may act as: yourmembrane enzymes structural support Ithindelto mediators of changes in membrane a shape alcohol utc 2) Transmembrane proteins – aci relist dtoo me carbol fuchsin (pinkIred) penetrate membrane completely Primary - 1 ACID-FAST CELL WALL (AFP) Mordant-Heat 2 - channels for substances 3). alcohol 3. decolorizer - Acid blue u Counterstain methylene - characteristic - characteristic of all Mycobacterium ~ unique General functions of Plasma membrane acidfata spp. and certain pathogenic Nocardia spp amount of type lipid partially fact adid 1) selective permeability acid fate fast) ~ - high conc of mycolic acid (~60%) – passive mitochondraa I give prevents the uptake of stains facilitated Eukaryotic Gram staining active 2) breakdown of nutrients and produce ATP CYTOPLASM - cell substance inside plasma membrane - ~80% water and contains primarily proteins carbohydrates lipids separate to aironment pla inorganic ions PLASMA MEMBRANE ~ other low molecular weight substances - thin structure lying inside cell wall and Major structures enclosing the cytoplasm materials - phospholipids and proteins 1) Nucleoid - aggregation of genetic 6 Psalm 56:3 When I am afraid, I put my trust in you.  Nucleoid. MLSBACTC CLINICAL BACTERIOLOGY [LEC] 2) Ribosomes 30S – smaller subunit containing 1 3) Inclusions Storage form of ~ other substances molecule of rRNA some bacteria - 80S ribosomes – eukaryotic cells a ~ sudber NUCLEOID - contains long, continuous and INCLUSIONS storage structure - frequently circularly arranged thread of - reserve deposits containing certain dsDNA (bacterial chromosome) nutrients - spherical, elongated, dumb bell DNA is simple has extrachromosomal shaped Metachromatic granules - Plasmid – small, circular, dsDNA DNA) virulence) not attained - large inclusions that may stain red w/ - extrachromosomal DNA and are in main certain blue dyes like methylene blue to another associated with plasma membrane - collectively known as volutin factor n transaorproteins - reserves of inorganic phosphate that throug - carry genes for antibiotic resistance, can be used to synthesize ATP tolerance to toxic metals, production of - characteristic of Corynebacterium toxins or synthesis of enzymes diphtheriae Polysaccharide granules - consist of glycogen and starch - presence demonstrated using iodine Glycogen = reddish brown Starch = blue RIBOSOMES - protein synthesis sites - 70S ribosomes – prokaryotic cells 2 subunits – consist of protein and ribosomal RNA 50S – larger subunit containing 2 molecules of rRNA subunit-not additive 7 Psalm 56:3 When I am afraid, I put my trust in you.  Lipid. MLSBACTC CLINICAL BACTERIOLOGY [LEC] Lipid inclusions - several hours and triggered when key nutrients become scarce or - seen in various spp of Mycobacterium, unavailable Bacillus, Azobacter and Spirillum - Poly-β-hydroxybutyric acid – DIPICOLINIC ACID/CALCIUM common lipid storage material DIPICOLINATE - presence can be demonstrated using - organic acid in endospore that protects fat stains such as Sudan dyes DNA from damage Sulfur granules sport - found in bacteria that derive energy from oxidizing sulfur and sulfur- S containing compounds Acidithiobacillus spp - as energy reserve ENDOSPORES ~ diff. from fungi spores - “resting” cells formed by Clostridium spp and Bacillus spp - highly durable dehydrated cells w/ thick walls and additional layers - can survive extreme conditions extreme heat lack of water exposure to many toxic chemicals and radiation sterilization killed ~ spores can be SPOROGENESIS/SPORULATION - endospore formation in vegetative cell 8 Psalm 56:3 When I am afraid, I put my trust in you.