MICRO test 1
What does alcohol do in the gram stain?
-What founds out if G+ or G-? -Pokes holes into G- layer, losing crystal violet and removing dye
The S-layer:
-a single layer if thousands of copies of a single protein -produced only in hostile environments -found only in G+ or G- bacteria
Lysogeny only undergoes which phases?
-adsorption, penetration -goes right to prophage state
Historical use of microbes by humans
-affect how we lose and gain weight -used to treat wounds and in food -produce chemicals that keep bacteria away
Envelope
-around capsid -can change -viruses take with them a bit of cell membrane in the form of an envelope
What are microbes?
-bacteria, fungus, virus, protozoa, algae, archaea -tiny but mighty -need magnification to see! -reproduce rapidly-20 mins or more
Spikes
-can be found on enveloped or naked viruses -project from nucleocapsid or envelope -allow viruses to dock with host cells-receptors viruses use
Monolayer
-cell forms -single sheet of cells that supports viral multiplication
Enveloped viruses can bud from:
-cell membrane -nuclear envelope -endoplasmic reticulum
Mycobacterium and Nocardia:
-contains mycolic acid ( a wax): long chains of fatty acids -modified gram + structure -must use acid-fast chain to ID: -TB -leprosy
The gram stain:
-crystal violet gets into peptidoglycan layer
Satellite viruses
-dependent on other viruses for replication -invade cells that have already been infected
Bacterial endospores:
-dormant bodies -hardest of all life forms -heat resistant to survive -absence of water -cortex: made up of sugars
Viral envelope
-exposed on the outside of the envelope in place of membrane proteins
Prions
-fibrils in brain -cause brain not to work well
SOME but not all bacterial cells possess:
-flagella -pili -fimbriae -outer membrane -plasmids: circular nonessential pieces of DNA -inclusions"nutrientstorage -endospores -nanotubes
Complex capsid
-found in viruses that infect bacteria -NOT enveloped -may have multiple types of proteins
Thomas Huxley:
-found microorganisms and named them bathybius haeckelii=was actually gypsum
Ernest Haeckel
-imagined the 1st life forms and called them monera -drew pictures of imagined microbes **Monera story: solitary from greek
Lipopolysaccharide
-in upper membrane/outer most layer of outer membrane -can be toxic -referred to as lipid A and endotoxins=stimulates fever and shock
T-even bacteriophage
-infect E coli -land on surface of bacteria
Prophage
-inserted into bacterial chromosome -only in bacterial cells
Parasites
-intracellular parasites: can live within cells-most extreme
Delta agent
-known as hepatitis D -associated with hep B -naked circle of DNA -expressed only in presence of hep B virus
Thiomargarita namibiensis
-largest known bacterium -0.1-0.75 mm -Sulfur pearls
Lysogeny
-latent/dormant state-temperate phages -"silent virus" -prophage: viral DNA enters into an inactive state until where it stays temporarily -induction: virus in a lysogenic cell becomes activated and replicates
Exponential growth
-logarithmic or log phase -more bacteria living than dying
L-forms:
-lose cell wall during its life cycle -play an important role in persistent infections that can be resistant to antibiotic treatment
Lytic state:
1. Absorption 2.Penetration: injects DNA/RNA 3. Replication 4. Assembly of parts/virions 5. Maturation phase
Biofilm formation steps:
1. Pioneer bacteria colonize a surface 2. Pioneer secrete extracellular material that helps keep them on surface and serves as an attachment 3. Other species join biofilm
Shortest generation time of growth
10-12 mins
Mycobacterium leprae generation time:
10-30 days
Robert Hooke
1660s/produced earliest record of microbes
When were viruses discovered and by who?
1905/Ivanovski
The amount of time required for a complete fission cycle from parent to two daughter cells ?
Generation time ** or doubling time
What binds to crystal violet and gets bigger?
Grams iodine=Mordant(biting)
Holds DNA together?
H proteins
Retro Virus
HIV/AIDS
Semmelweis
Handwashing
Produced gram stain?
Hans christian Gram in 1884
Adsorption:
Virus latches onto cell
Creutzfeldt-Jacob's disease:
affects CNS/brain
Recombinant DNA technology
alter DNA to make specific product/transferring genetic material
Optimum temperature
an intermediate between the minimum and the maximum which promotes the fastest rate of growth and metabolism
Biogenesis
beginning with life
Spontaneous generation/Abiogenesis
beginning without life
Mutualism
both member's benefit
Minimum Temperature
the lowest temperature that permits a microbe's continued growth and metabolism
Obligate aerobe
cannot grow without oxygen
Nucleocapsid
capsid + nucleic acid
Persistent infection
cell carries the virus but is not lysed.
Herpes zoster virus
chickenpox and shingles shingle effect takes place at end of nerve cell-stays there until activated /associated with stress
Superoxide dismutase
combines with couple of O2 to form hydrogen peroxide + O2
Catalase
converts hydrogen peroxide to water and oxygen
Retroviruses:
create DNA out of RNA **HIV
RNA viruses get into?
cytoplasm
Capnophiles
grow best at higher CO2 tension
Iron
important component of cytochrome proteins of cell respiration
Sodium
important for certain types of cell transport
In Vitro
in cell or tissue culture (often isolated animal cells which form a monolayer)
In Vivio
in laboratory bred animals and embryonic bird tissue
Obligate halophiles
inhibit salt lakes, ponds/grow optimally at solutions of 25% NaCl
What are grown in vitro?
isolated animals
Nanotubes
launch extensions that retrieve electrons
How animal viruses penetrate?
leaves coat(envelop) at membrane method, envelope fuses with membrane of cell/only capsid comes in
Spontaneous generation/Vital forces
life came from non-life(invisible vital forces)
Osmophiles
live in habitats with high solute concentrations
endoparasites
live inside organs and tissues
ectoparasites
live on body
Intracellular parasites
live with cells such as leprosy bacillus and syphilis spirochete
What do viruses require as their medium
living cells
What does positive-stranded DNA make?
mRNA
Obligate parasites
unable to grow outside of a living cell
Biorememdiation
use of microorganisms to restore environment stability/clean up toxic pollutants
Chemmoorganic heterotrophs
use organic compounds for energy and inorganic compounds as a carbon source
Penetration/uncoating
virus is engulfed by cell and enclosed in vesicle or vacuole/envelope and capsid dissolved/releases nucleic acid into cytoplasm
What are cytopathic effects?
virus-induced damage to the cell that alters its appearance
Oncoviruses
viruses capable of initiating tumors
Release:
when its parts are assembled and released
Stationary growth phase
equal bacteria dying as living
Zinc
essential regulatory element for eukaryotic genetics major component of "zinc fingers;" binding factors that help enzymes adhere to specific sites on DNA
Basophiles
exert under pressure up to 1000 times atmospheric pressure
Pilus
extensions that draw bacterium close enough to transfer DNA to it
Fimbriae
extensions that help in adhesion to other cells and surfaces
Genus part
first letter=capitalized
What are multiple branches of a basic rod structure?
Branching filaments
Staphylococcus aureus
can grown on NaCl media ranging from 0.1-20%
The life cycle of dsDNA viruses is divided into 2 parts-
early and late phases
What does bacteria like to grow on?
embryonic tissues/eggs
Psychrotrophs
optimum temperature between 15°C and 30°C
Symbiotic
organisms live in close nutritional relationship
Greatest impact on microbial growth ?
oxygen
Assembly:
parts are assembled to form virus particles
Smallest viruses?
parvoviruses around 20 nm in diameter
Virus =
poison
Lag phase
prior to growth/nothing appears to be happening
Capsid
protein shell that surrounds nucleic acid
Exotoxins
released when cells are alive
Endotoxins
released when cells die
Lithoautotrophs
rely totally on inorganic minerals and require neither sunlight nor organic nutrients
Microaerophiles
requires small amount of O2, harmed in normal atmospheric concentrations
Facultative halophiles
resistant to salt
What forms gypsum?
sea water + alcohol
Species part
seconds letter=lowercase
Heterotrophs
seeks organic source of food outside of itself
Viable nonculturable state (VNC)
so dormant that although they are alive, they won't grow on culture medium/missed in colonies
Tropisms
specificities(limit or range) of viruses for certain tissues
Glycoproteins:
spikes on envelope bind to cell membrane receptors
Calcium
stabilizer of cell wall and endospores of bacteria
Magnesium
stabilizer of membranes and ribosomes
Herpes simplex virus
stores itself in some of the nerves and later develops-cold sores and genital herpes
Maximum Temperature
the highest temperature at which growth and metabolism can proceed before proteins are denatured
Host Range:
the limited range of cells that a virus can infect **only can infect cells where glycoproteins match with receptors
Lysogenic conversion:
**when a bacteria acquires a new trait from its temperate phage EX: Corynebacterium diphtheria- diphtheriae toxin Vibrio cholerae-cholera toxin Clostridium botulinum-botulinum toxin
Cytoplasmic membrane
- A lipid bilayer with proteins embedded -Provides a site of reaction: enzymes or respiration and ATP synthesis -Sterols: regulates passage of nutrients
MOST bacterial cells possess:
- cell wall -surface coating called glycocalyx
Biofilm
-1 species caused by another species/mixed communities of bacteria -epitome of synergy -develop internal streams: take waste away and brings in nutrients
Gram Positive cell:
-5 layer thick peptidoglycan wall -One membrane
Cytoplasm:
-70-80% -Soluble proteins, salts, and carbs -Site of nearly all chemical reactions -Contains DNA in nucleoid
Bacteriophage
-A virus that infects bacteria -Bacteria eaters -Discovered in 1915 -Most are dsDNA -Often increase bacterial virulence
Woese-Fox System
-An entirely new system was proposed based on domains: -Bacteria -Archaea -Eukarya
Joseph Lister
-Aseptic techniques -Disinfecting hands and air with strong antiseptic chemicals such as phenol
Thermoduric
-Can survive short exposure high temp -Common contaminants of heated or pasteurized foods -Cyst of Giardia(Protozoa), spores of bacillus and clostridium
Prokaryotes consist of?
-DNA/Cell wall(peptidoglycan)
Disease caused by toxin of bacteria getting sick:
-Diphtheria -Cholera -Botulism
RNA viruses
-Double stranded(Rotavirus): infect stomach/intestines -Positive-sense RNA(Corona/HIV): makes proteins and negative strands/same as mRNA -Negative-sense RNA(Influenza): has to make positive strands first before proteins
Louis Pasteur
-Father of microbiology -Fermentation of alcoholic beverages/discovery of yeast -Used a series of experiments with swan-necked flasks to disproved biogenesis/spontaneous generation, transformation theory of disease and the miasma theory -proved bacteria caused disease
Responsible for microscope?
-Hooke and Leeuwenhoek
Robert Koch
-Isolated infectious organisms to determine disease -Associated microbe to a disease
Prokaryotic shape and arrangement:
-Most are unicellular organisms: -colonies or biofilms
Cell wall deficient bacteria?
-Mycoplasmas -L-forms
Biofilm structure
-O2 and pH varies
Thermophile
-Optimum temp over 45 degrees Celsius -Heat loving microbes
Synthesis/Replication:
-Production of proteins -Nucleic acid is acting on cell -mRNA starts being translated into viral proteins=viral replication
2 acids in gram positive used to repel WBC?
-Teichoic acid -Lipoteichoic acid
Gram negative cell:
-Thin peptidoglycan(Peri-plasmic space) -2 membranes -Porins: in outer membrane
Flow cytometer:
-measure stream of cell going by/differentiates among cell sizes and if cells are alive -labels cell fluorescently -identifies pathogens and pt specimens
Pasteur and the theory of disease:
-microbes are responsible for fermentation -originated pasteurization -protozoans were responsible for silkworm diseases
Quorum sensing:
-monitor size of their own populations -turns on genes
Viroid's
-naked strand of RNA//without capsid -plant parasite
Mycoplasmas:
-naturally lack a cell wall -stabilized by sterols and resistant to lysis
spongiform encephalopathies
-noncellular infectious agents -contains prisons
Psychrophile
-optimum temp below 15 degrees Celsius -storage in refrigerator causes them to grow -grow in cold conditions
Non symbiotic
-organisms free living -relationships not required for survival
Cancer causing genes:
-papillomavirus -Epstein Barr virus -HTLV-1: human T cell leukemia
Rusticles
-part of biofilm created by bacteria deep in ocean -bacteria creates from rust
Cytoskeleton:
-peptidoglycan layer determines morphology -made up of actin, tubulin, and intermediate=filament proteins
Specialized transduction
-phage only with him the same gene every time it invades
Generalized transduction
-phage takes any gene/DNA
Capsid:
-protein coat: made of proteins -capsomeres: subunits of proteins -nucleocapsid
What does lytic cycle do?
-releases viruses/bacteriophages to other cells -destruction of cell
Types of CE's:
-shape and size -development of inclusion bodies -syncytia: merging with different cells
What toxic products is oxygen transformed into during cellular reactions?
-single O2 -superoxide ion(O2-) -hydrogen peroxide(H2O2) -hydroxyl radicals(OH)
DNA viruses:
-single stranded -double stranded: linear, circular
Viruses structure:
-smallest infectious agents
How are viruses classified?
-structure -similarities in genetic makeup
Glycocalyx
-sugar capsule -slime coat when bacteria doesn't stick together
Nomenclature:
-the assignment of scientific names -binomial nomenclature
Early phase of dsDNA?
-viral DNA enters nucleus and becomes RNA(xcription) -RNA moves to cytoplasm and becomes viral(xlation)
Provirus
-viral DNA is incorporated into the DNA of host -exist only in animal cells
Ways that viruses cause cancer in animals:
-virus carries oncogenes -virus turns on cell oncogenes -virus has proteins that cause uncontrolled cell growth
Virophages
-viruses that invade viruses -they infect larger viruses -they need larger viruses to replicate -they infect cells already infected by other viruses -they reduce virulence of host virus
Parasitism
1 benefit, 1 harmed
Peptidoglycan
2 long chains of sugars
Synergism
2 members cooperate and share nutrients
Mesophiles
20-40 degrees Celsius/Optimum 37 degrees Celsius
Average generation time of growth
30-60 mins
What percentage of diseases are caused by biofilms?
70-80%
What percent of human DNA consist of viral DNA sequences?
8%
What % of water is biofilm
90%
Lanosterol
=bacteria uses
Microbes are ubiquitous
=everywhere -first cells in the evolution of time
Purple bacteria?
=gram +
Red bacteria?
=gram -
Gastric ulcers
=helicobacter pylori
Cholesterol
=humans use
General phases of the animal viral replication cycle:
Adsorption, Penetration, Synthesis/Replication, Assembly, Release
Irreductable complexity:
All parts needed for it to work
What produce S-layer?
Clostridium difficile and bacillus anthracis
What is spherical or ball shaped?
Coccus
What replaces crystal violet?
Counter stain
Staphylococcus aureus/Listeria
Custard and lunch meats
1 bacterial chromosome=
DNA
What do viruses need to reproduce?
DNA
Central Core:
DNA or RNA, matrix proteins, enzymes-not in all viruses
Pleomorphism
Different shapes/same species
facultative anaerobes
Do not require O2 but use it when present
Aerotolerant
Do not use O2 but can detoxify it/lacks enzymes for processing toxic O2
Coulter counter:
Electronically scans fluid that passes through pipette
Grow wherever suitable?
Endospores
How does cell population size grow?
Exponentially 2 to the 0, 2 to the 1, 2 to the 2, etc
Can only infect liver cells?
Hep B
Bovine Spongiform Encephalopathy
Mad cow disease/contaminated beef
Direct cell count
Microscopically observe and count
Acid-fact bacteria?
Mycobacterium and Nocardia
Anaerobes
Neither use or detoxify O2 Ex: pylori, oral/intestinal bacteria
Make make up virus?
Nucleic acid + Capsid
Where is DNA located?
Nucleoid
Influences microbial growth the most?
O2, CO2
Will prevent synthesis of cell wall?
Penicillin
In gram negative what makes up cell wall?
Peptidoglycan + lower membrane
The danger of lysogeny in human disease:
Phage can cause virulence-toxins
Lipid bilayer:
Phospholipids: 30-40% Proteins: 60-70%
What will destroy endospores?
Pressurized steam at 120 degrees Celsius for 20-30 mins
Prokaryotes vs Eukaryotes
Prokaryotes: no nucleus Eukaryotes: Does not have peptidoglycan
Reverse Transcription makes?
RNA
What is spindle-shaped, threadlike rods
Rods/Bacillus
What are slightly curved or spiral shaped?
Spirillum
What is a flexible form resembling a spring?
Spirochete
Making of spores?
Sporulation
Aerobes
Use oxygen and detoxify it Ex: bacillus, mycobacterium, TB, fungi, protozoa
What are singly occurring rods that are slightly curved?
Vibrio
Growth curve
a predicable pattern of a bacterial population growth
Pathogens
can cause damage to tissues or even death range from viruses to helminths
chemotroph
microbes that gain energy from chemical compounds
Plaques
microscopic manifestations/clear patches in cell culture that indicates sites of virus infections
Largest virus?
mimiviruses around 450 nm in length
Death phase
more dying than living **Some go dormant/some produce spores
Shy-Drager syndrome or MSA
multiple system atrophy
halophiles
need salt
DNA viruses get into?
nucleus of invaded cell(animal)
Chronic latent state:
ongoing/stored
Commensalism
only 1 member is benefited
Which plants do viroid's parasitize:
tomatoes, potatoes, cucumbers, citrus trees
Transformation
transforming of cells
