Micro 2420 Second Half Flashcards

Question

Quorum Sensing

Answer 1

- assessing bacterial density via autoinducers - autoinducers easily move in and out of cells - causing a coordinated response by all cells in the community Process: - autoinducers bind to the receptor if the concentration of autoinducers is high enough - If this happens, this complex turns into a transcription factor and starts protein transcription - If not a high enough concentration, these proteins are not transcribed (not enough bacteria in the environment) Produced by QS: - EPS secretion - biofilm dissolution - expression of virulence factors

Answer 2

Ascomycota and Basidiomycota

Answer 3

Invisible to the naked eye - yeast - mould

Answer 4

produce fruiting bodies - mushrooms - puffballs - truffles

Answer 5

Cell Wall: - glucans or chitin (beta 1,6 or 1,3- glucan) Inner cell wall - glucans - chitin - phospholipid bilayer Outer cell wall: - mannan and mannoproteins (yeasts) Cell membrane: - ergosterols (similar to animal cholesterol- hard to isolate and treat)

Answer 6

- nutrient cycling (decomposers) - organic to inorganic matter - use secreted enzymes to extracellularly break down nutrients into small enough to absorb

Answer 7

- sometimes multinucleate - sometimes septate (individual cells) - sometimes non-septate - sometimes pseudohyphae (bud and for, yeast) Mycelium - mass of hyphae - spores germinate to reproduce and form hyphae Fruiting Bodies - forms of mycelium - spore forming

Answer 8

- moth micro and macro produce spores Spores: dormant structures to resist environmental stress - for dissemination Sexual: - meiospores (basidiospores, ascospores) - in sexual fruiting bodies Asexual: - mitospores (conidospores, sporangiospores) - in asexual fruiting bodies

Answer 9

- conidophore asexually germinates (mitosis) - Conidophore produces conidospores (conidia - mating type -) - these spores can regerminate to continue asexually or meet up with a mating type +

Answer 10

- mating type + meets with a mating type - (conidia) Plasmogamy - cytoplasms fuse without fusing nuclei - makes a dykaryotic cell with dikaryotic hyphae - prolonged dikaryotic hyphae state - ascus has two nuclei Karyogamy - fusing of nuclei in ascus to make a diploid zygote Meiosis - reduces diploid into 4, 8, 16, etc haploid (non identical) After Meiosis - haploid spores produced (ascospores) - These are in an ascocarp in asci - these will disperse and germinate to either asexual or sexual reproducers (depending on nuclei)

Answer 11

- 3-10um - budding - can be strings (pseudohyphae) or hyphae e.g - saccharomyces cerevisiae - Candida albicans (dimorphic) - Cryptococcus neoformans (capsule)

Answer 12

Haploid (n) - starts with ascus with ascopores - these are not individual yeast cells and can bud - these can release pheromones to connect other yeast - shmoos (under stress conditions) - these undergo nuclear fusion and create diploid cells (2n) Diploid (2n) - mated schmoos can bud - when nutrients are low these diploid yeast will undergo meiosis to produce 4 haploid non identical daughter cells - these will also sporulate - produce ascus with ascopores

Answer 13

- Candida (yeast infection) - Cryptococcus (meningitis) - Aspergillus (breath in spores - resp infection)

Answer 14

Ustilago maydis - causes corn smut (black dust on corn)

Answer 15

- mutualism - between plants algae or cyanobacteria and fungi - fungi get carbs produced by photosynthesis - fungi gives water and nutrients - fungi physically protect photobiont

Answer 16

- mutualism - fungi extends root system of plants - fungi get photo products - fungi give water and nutrients - arbuscules - grow IN the root cells of plants and allow for nutrient exchange

Answer 17

- acellular - Family: viridae - obligate parasites - tropism - specific host or host range - virion - inanimate particles - wide range of genomes - innocuous and lethal effects

Answer 18

- only viruses reach risk level 4 - Filoviridae (fevers and internal bleeding - hemorrhagic fever) - Ebola - organ failure and internal bleeding (hemorrhagic fever)

Answer 19

- bacteriophages used as an alternative to antibiotics and disinfectants in infections - bacteriophage used in molecular cloning (cloning vectors) - viruses are modified and used as delivery vehicles for gene therapy - horizontal gene transfer (transductions) - increases genetic diversity

Answer 20

- capsid - genome (RNA or DNA) - envelope in some cases - tegument in between capsid and envelope if present (helos cell prepare for replication)

Answer 21

Baltimore Classification - relationship between genome and mRNA produces - coding strand (looks similar to mRNA) - + sense - template strand (actually transcribed) - -sense - the mRNA is + sense because it resembles the coding strand

Answer 22

- double stranded DNA - uses DNA polymerase for rep - +/- sense DNA (bc double stranded) - bacteriophage lambda (effects ecoli) - Herpesvirus (chickenpox, genital virus) - Papillomavirus (warts and tumors)

Answer 23

Single-stranded DNA negative sense - requires reverse transcription from host to make coding strand (+) to make double stranded DNA

Answer 24

Single-stranded DNA positive sense - requires DNA polymerase to make template strand

Answer 25

Double-stranded RNA (+/-) - requires RNA dependant RNA polymerase to make mRNA and RNA

Answer 26

Single stranded positive sense RNA - RNA dependent RNA polymerase to make a template strand then replicate (makes RNA to make mRNA) - Coronavirus - Flaviovirus - Hep C, Zika Virus

Answer 27

Single stranded negative sense RNA - RNA dependant RNA polymerase makes mRNA - Filovirus - Ebola - Orthomyxovirus - flu

Answer 28

Positive sense single stranded RNA - has own reverse transcriptase to make double stranded DNA (makes DNA to make mRNA) - lentiviruses - HIV

Answer 29

- filamentous capsid (ebola) - Icosahedral capsid (polyhedral) - complex viruses: bacteriophages Also classified based on presence or absence of envelope

Answer 30

- usually very small Very Large String - Ebola virus (80x970nm) Large polyhedral - Herpes (200nm) Medium circle - Influenza virus (100nm) small circle - human papilloma virus (60nm)

Answer 31

1) attachment 2) penetrate 3) uncoating 4) biosynthesis (complicated by presence of envelope and nature of genome) 5) assembly 6) release Lytic - breaks free Lysogenic - keeps in tact (herpes is forever)

Answer 32

1) removing partner kills or reduces the growth of the other 2) genomes show advanced degeneration (bc they rely on each other) 3) The products produced are used by the other eg Lichen

Answer 33

1) Each partner benefits 2) partners can be easily separated and grown independently eg cow rumen microbiome

Answer 34

1) One species benefits 2) Other species are unaffected eg Beggiatoa and other sulfur spring microbes - often at high temperatures - oxidize sulfur for energy - decrease toxicity - allows other species to live

Answer 35

1) One species benefits 2) other species harmed 3) interaction is non-specific - not one-to-one - not trying to kill another species just trying to get nutrients eg Streptomyces and other soil bacteria - produce antibiotics - This kills and lyses other bacteria in soil - These bacteria then release their nutrients for consumption by Streptomyces

Answer 36

1) One species benefits 2) other species harmed 3) specific and usually obligatory for the parasite eq legionella pneumophila (lung lover), ameba, human lung macrophages - causes legionaires disease - infect fresh water amebas -

Answer 37

- Many insect species are infected by intracellular bacteria - endosymbionts eg Wolbachia - gram - bacteria - present in 50% of all insect species - harmless to humans - protects mosquitos from viruses - bacteria compete with malaria parasite - affects gametes - passed on through genes

Answer 38

1) who is there? 2) what are they doing? 3) how do they respond to different conditions?

Answer 39

- culture doesn't support many species - most bacterial species cannot survive lab conditions because they are so different (not used to abundant nutrients) - some depend on other species - viable but non-culturable - outside host, they do not culture even in very similar conditions

Answer 40

- invented agar plate - used to use gelatin - which is not stable at high temps

Answer 41

species that live in an environment where nutrients are not abundant - lake - pond water - low in nitrogen and phosphorus (clean water because no algae growth)

Answer 42

attentive to and concerned about details - bacteria get nutrients in a certain way

Answer 43

- automating many processes of culturing - allows culturing under hundreds of conditions

Answer 44

- not used much - target gene amplified with PCR - specific genes are barcoded with a known sequence tag - sequenced ALL AT ONCE - commonly amplifies 16S rRNA in bacteria - can only look at bacteria (16S) - amplicon bias - fast because all at once

Answer 45

- gDNA broken into bits - barcoded - directly sequenced - sequence ALL - allows you to pull out specific genes in the sequence pool - WHOLE gene - too much data maybe - can look at archaea and protists - not just 16S

Answer 46

- extract mRNA from all RNA (90% tRNA and rRNA) - transcribe to DNA (viral reverse transcriptase enzyme) - barcode - sequence - match transcripts to a known genome to identify - allows us to look at what proteins are actively being transcribed and, therefore, what is happening in a community - what genes are active? - RNA has a shorter half-life, and therefore, we only see the currently alive RNA compared to DNA - waste a lot of tRNA and rRNA

Answer 47

- look at metagenomics - use a computer to assemble a metagenome assembled genome - software can predict possible functions - Who is at the concert?

Answer 48

- extract all proteins - sequence these peptide fragments by mass spec - use computer to match peptides to proteins and proteins to genes - limited by chemistry to break down the proteins - can see which genes are being transcribed and are present - who is actually causing the reactions from the environment?

Answer 49

- metabonomics - extract all molecules - use mass spec and NMR - computer matches these compounds to obtained spectra standards - see what is being made but not who made it - much data - what are the biproducts of this concert?

Answer 50

- RNA sequencing - mRNA reflects active transcription - what the cells are actually making in response to the environment - how are the people responding to the concert?

Answer 51

- previously, it was thought that the ocean had no microbes - he said there was using a microscope - ocean microbes are unculturable for the most part - ocean microbes are oligotrophic - less nutrients - demonstrated that decom in ocean is 100x slower than on land (less microbes) - told people to stop dumping trash in ocean

Answer 52

Alvin sank - Bologne sandwich edible after 1 year Sorcerer II Global Ocean Sampling (25000 diff microbes/L of ocean water) - 70% previously unknown - in 1mL ocean water - 10bill viruses, 1mill bacteria, 1000 protists Tara Oceans, Tara Pacific - a multinational project collecting ocean samples - created Ocean Microbiomics Database - found temperature is has the largest effect on microbiome composition in upper ocean layers

Answer 53

- applying manufactured fertilizer pellets - microbes crowded out and killed - soil now lacks original microbes and cannot work without fertilizer

Answer 54

In each soil particle: - mini colonies - biofilms - filamentous bacteria - fungi humic substances - a mixture of nutrients and half-decomposed organic elements *definitely not oligotrophic (at least the top layer)

Answer 55

- Amensalism - non-specific - secrete antibiotics to outcompete other species - produce geosmin - responsible for smell of soil when it rains - humans can smell very trace amounts of it

Answer 56

- narrow region of soil surrounding plant roots - may fix nitrogen from atmosphere (contain diazotrophs) - give nitrogen to plants and in return get protection (contain fungi) - protect plants from pathogens

Answer 57

- fungi outside of root plant - colonize the rhizoplane - form coating around mantle - protect mantle - absorb nutrients and get sugar from plants *helpful in agriculture because they get nutrients

Answer 58

- fungi inside root cells forming arbuscules - bacterial or fungal - lack sexual cycles - very few species but VERY IMPORTANT to ecosystem - arbuscules within plant root cells - hyphae

Answer 59

- grow with plant tissue - bacterial, fungal e.g plant roots and rhizobia - these act like nitrogen mixing organs - legume plants - beans, peas *pink - because of leghemoglobin - nitrogenase denatures at atm O2 levels - the leghemoglobin binds to O2 to keep it away - provides a steady conc of O2 to allow for nitrogen fixing to occur

Answer 60

- microbes found at non-sterile body sites - live within host but do not affect host - This may not be true - We may just not know their effect to the host

Answer 61

- help them digest cellulose

Answer 62

- help them digest dietary substrates eg Termites - digest wood (lignin, cellulose) - microbiome composition and function very conserved Demoxmites - very efficient microbiota - eye hair mites - clean - do not poop very often

Answer 63

1:1.3 human:bacteria - Bacteria cells are 1/100 to 1/1000 the size of human cells

Answer 64

The different bacteria/viruses/fungi found in the microbiome

Answer 65

- microbiome has distinct patterns governed by sleeping, eating, hormones - chronicity lost in diseases like type 2 diabetes

Answer 66

- Very difficult to colonize (dry, acidic, salty, oils) - 10^12 microbes in moist areas - mostly gram + because thick peptidoglycan layer eg - staphylococcus epidermis - helps maintain skin health and modulates immune response - Cutibacterium acnes - degrades skin oils - inflames sebaceous glands - allowing other bacteria into the damaged skin

Answer 67

Autism - neural signals affected by the gut Colorectal Cancer - oral health is linked (plaque) Type 1 Diabetes - due to hangober of use of antibiotics Chronic Depression - some microbes induce immune respone producing cytokines linked to cancer, also produces serotonin Parkinsons - start with an upset stomach, vagus nerve sends signals

Answer 68

entity formed by association of different species - we are holobiles

Answer 69

Human Infant - non pathogenic Neisseria spp. (G-) - streptococucs (G+), Lactobacillus spp. (G+) (from milk) Teeth - provotella fusobacterium spp. between the gums and teeth - long and thread like - streptococcus mutans (tooth enamel - eats glucose, produces acid, causing cavities) *mostly strict anaerobes - usually under gum line - form plaque to reduce O2 access - biofilm

Answer 70

Oral and respiratory tract

Answer 71

Nostrils/nasopharynx - Bacillota, Actinomycetota - usually ones genus or species dominates over others (why?) - this means there is the potential of producing novel probiotics to target Nasopharynx - Staphylococcus aureus - Staphylococcus epidermidis - some strains very antibiotically resistant, some not Oropharynx - similar to saliva

Answer 72

- once thought to be sterile so no one looks for microbes - MOSTLY anaerobes - weird - microbiota in COPD, cystic fibrosis, asthma are distinct and diff from healthy lungs - mucocilliatory escalator - cilia beat in time to sweep particles out of lungs back to swallow Bordetella Protasis - Whooping cough - caused by toxin

Answer 73

- kidneys, urinary, bladder, normally serile or close too - except in UTI caused by S. Epidermis or members of Enterobacteriaceae - composition of gut microbiome changed with menstrual cycle - acidic - favours lactobacillus spp. - frotects from STIs and improve reproductive success - diversity not considered a good thing - Bacterial Vaginosis - too much diversity

Answer 74

- low pH - few microbes survive - Helicobacter pylori - at pH 1 -burrows in mucus -causes ulcers

Answer 75

- reduce stomach acidity - caused by malnourishment - deliberately caused by using PP1 - can lead to intestinal disease

Answer 76

- mostly anaerobic species - colon (transverse) -

Answer 77

- did not have similar species in gut but had similar "pathways" - these are metabolic potentials

Answer 78

- birth, breast feeding, interaction with env

Answer 79

- help regulate the immune system (help the immune system recognize beneficial vs harmful pathogens - help extract energy from food (fermentation, metabolites - SCFA, butyrate) - control potential pathogens (competitive inhibition, some chemicals communicate with pathogens and tell them to stop behaving like pathogens) - make vitamins (B,K), minerals, and cofactors - improve intestinal functions (microbes manage neurons so we dont feel digestion) - detoxify toxic compounds and carcinogens (can also work the other way and create toxic compounds

Answer 80

not a natural biotic, food preservatives, these can be metabolized to be more active, less active, or harmful, depending on your microbiome

Answer 81

Allura red, yellow (tartrazine) - can be metabolized to harmful (carcinogens) - harmless if not in gut Avoid: - artificial emulsifiers - caragenan (in metabolized to polygenan which irritates the gut, and can induce cancer)

Answer 82

- the microbiome is reduced because people do not get as many microbes in a clean environment, eating preserved food - This could also be because of antibiotic use - step like loss every 20 years (generation)

Answer 83

- emulates the human gut - microbes reach a steady state - help culture the unculturable because microbes live together - can help us learn to protect against perturbations

Answer 84

- MB is kept in check with physical barriers - damage or penetration, or genetic defects, can affect this - MB not in balance - pathobionts/opportunistic pathogens are normal microbes that cause harm under unfavourable conditions - patient can be affected repeatedly

Answer 85

- competitive exclusion - environment modifications (Lactobacillus lowers pH in vagina) - Host stimulation (bacteroides fragilis stimulate host cytokines and regulate the immune system to prevent colonization by pathogens. - Direct pacification - secreted factors by gut MB prevent expression of Salmonella and other food-borne pathogens

Answer 86

- composition of gut affects body and mood - switching microbiomes in rats switches behavior

Answer 87

- Containment Breach (eg cancerous legion in colon allows microbes to penetrate deeper and cause infections) - Niche Disturbance (eg ecosystem changed through exposure to xenobiotics, infection, or lifestyle) - Extinction Events (eg losing a taxa in an ecosystem)

Answer 88

- microbiome is different in obesity but differs btw people - obesity associated with less diversity - also associated with low grade intestinal inflammation (loss of microbes that allow for defense causing strengthening of tight junctions and immune system activation)

Answer 89

- MB is known and defined - includes germ free animals (no MB) - expensive but valuable

Answer 90

- poor immune systems - low cardiac output - need more calories (gut microbiome cannot break down - b/c none) - thin intestinal walls (don't have to protect against anything - stunted villi) - abnormal, large ceca (like the colon - MB) - odd behavior - misshapen mitochondria (not receiving signals)

Answer 91

- born with an impaired immune system (known before birth) - SCID (lethal mutation) - c-section in sterile environment - bone marrow transplant from sister - lived in bubble for 12 years - sister had Epstein Bar Virus and the brother died

Answer 92

- non adaptive or non specific - rapid response Includes: - physical Barriers - chemical and cellular responses (if barriers are breached) *present at birth and not acquired

Answer 93

- contact with infectious virus does not always lead to disease To cause disease the pathogen must: - breach host defenses - survive innate mechanisms - begin to multiply

Answer 94

- connects all phys barriers - specialized cells monitor all phys barrier and present antigens to immune cells in lymph nodes Primary Lymphoid Organs: - produce lymphoid cells - bone marrow Secondary Lymphoid Organs: - stations for antigen encounter - lymph nodes swell when you are sick SALT and GALT - skin and gut associated lymphoid tissue

Answer 95

- made in liver - circulates in blood - very small proteins - inactive but activated by proteolytic cleaving - 30 - soluble - C1 - C9 Have 3 activation pathways for complement system: - classical - lectin - alternative *they all converge to the lytic pathway

Answer 96

- small protein fragments secreted by cells - affect other cells - alerts other cells to presence of virus eg Interferon - alert cytokine - once infected starts alerting - warns other cells - cells can put up defenses

Answer 97

- small molecules - able to lyse most microbial cells and enveloped viruses eg Defensins - in gut - secreted by paneth cells in crypt of epithelial tissue - attack the microbes that try and penetrate the tissue (not normal gut microbes)

Answer 98

- differentiate from myeloid bone marrow stem cells - cell that eats - hard to catch bacteria because both bacteria and phagocyte are negatively charged - C3b binds to bacteria and this binds to C3b receptor on the phagocyte making it easier to digest because it is closer - C3b binds to amines and LPS on many cells

Answer 99

- small - first to be deployed - catches bacteria in Neutrophil Extracellular Trap (NETosis) - suicide by neutrophils - spit out innards to make a net to trap bacteria (sticky) - other neutrophils or phagocytes can then more easily injest the bacteria Too much NETosis - lupus Too little NETosis - easier to infect *capsules interfere with NETosis - they are slippery

Answer 100

- circulate in bloodstream - attracted by chemical signals (cytokines) to site - Extravasation - as they travel through the blood vessels they differentiate into macrophages - macrophages secrete cytokines and thus cannot exist in the blood vessels because this would be too dangerous (septic shock)

Answer 101

- very large - ingest many bacteria at once - secrete cytokines - resident macrophages patrol different parts of the body eg Kuppfer cells in liver, langerhans cells in the skin, microglia in brain, alveolar macrophages in lungs

Answer 102

- long protrusions (arms) - arms allow them to squeeze through tight junctions and grab bacteria in gut - sample gut content

Answer 103

- close acting (this allows it to 'turn off' at long range) - 'hormone system' - small proteins - communication between body cells - good at signaling danger - Some cytokines also antinflammatory - reset homeostasis

Answer 104

Signs of acute inflammation: - heat at site - edema (swelling) - redness - pain - altered function - pus is dead neutrophils *usually a sign of infection

Answer 105

- mycobacterium tuberculosis - fish tank granuloma (pathogen from fish tank) - crohns disease

Answer 106

- phagocytes, macrophages, and dendrocytes can be APCs - process the digested antigens and display them on their surface for B and T cells to see - link the innate and adaptive immune system

Answer 107

- rich in M (microfold) cells - special site for uptake of antigens in gut for presentation to macrophages - transport from gut lumen to macrophages - to identify friend or foe

Answer 108

- slip out of NETosis - interfere with antigen recognition process - evade cytokine signals - allow them to evade the innate immune system eg - pneumoniae - Neisseria meningitis - Bacillus anthracis

Answer 109

- special cells in the innate immune system to recognize invariant and essential microbial factors unique to that microbe - PRRs - recognice MAMPs - Microbe Associated Molecular Patterns - they DO NOT discriminate between good and bad microbes

Answer 110

Toll Receptors (TLRs) - outside host cell - transmembrane receptors on some immune cells - recognize viral and bacterial products - MAMPs bind to ligand - stimulate inflammatory cytokines - induce macrophage production of antimicrobial proteins and peptides

Answer 111

NODs and NOD-like receptors (NLRs) - internal - bind MAMPs - activate cytokine production - form an inflammasome - activates adaptive immune system (triggers apoptosis)

Answer 112

- not phagocytic - not T and B cells - large and granular (perforin and granzyme) - 2% of body lymphocytes - innate defense - attack host cells overwhelmed by pathogens How: - infected cell presents as altered self via MHC I - immune system also labels infected cells with antibodies

Answer 113

- after apoptosis a series of events occurs to create neatly packed apoptotic bodies - neutrophils consume these through efferocytosis - allows for reduced inflammation

Answer 114

- memory - develops as need arises - weapons cache

Answer 115

- T cell teams recognize antigens displayed on infected cells and target infection in cells

Answer 116

- antibodies directly target invaders (B cell response) - target infections in bodies fluids

Answer 117

- develops over 3-4 days after exposure - immune system recognizes small antigen pieces (epitopes) - phagocytosis produces epitopes to show immune system

Answer 118

- how well do antigens elicit an immune response Best: proteins - carbs Worst: nucleic and lipids * because proteins can fold and are very selective - creating conformational epitomes

Answer 119

t cells born in bone marrow and moved to thymus for education - babies theoretically have t cells that can recognize EVERYTHING - each t cell develops a unique T receptor cell that reacts to a different random epitope - have to teach them to not recognize self Thymus - fully developed before birth and shrinks as you age Test 1: positive selection - can they identify self major histocompatibility complex peptides Test 2: negative selection - do they react against self antigens in the thymus - killed if tests failed - 98% die Thymus shuts down after birth and by puberty is basically gone - reserves of educated t cells are reserved and reproduce at a balanced rate

Answer 120

Seek and destroy cells presenting noxious antigens (infected)

Answer 121

- memorize infecting antigens - directing immune system on what to attack - alert B cells - connect B and T cells

Answer 122

- Th hells differentiate into memory T cells - in bone marrow - retain antigen affinity of original activated T cell - can clonally replicate (memory may get hazy)

Answer 123

- naive T cells differentiate into regulatory T cells - help restore homeostasis after an infection - lack of Treg - chronic inflammation

Answer 124

Infected cells and APCs place antigens for display on these glycoproteins MHCI - on surface of infected cell, kill infected cell MHCII - display antigens of APCs, used to alert army, knowledge, the cell is not killed

Answer 125

- reside in lymph nodes of the body - up to 10 T cells will recognize the same type - 4x10^11

Answer 126

- interaction with B cells - B cells in lymph nodes - born in bone marrow and are educated there - Helper T cells connect T and B cells - floating antigens binds to specific receptors on B cells specific to an epitope - If T cell presents the same antigen to a B cells as the one on the B cell it become activated (the B cell) - it then differentiates into a plasma cell (produce antibodies)

Answer 127

- 10 bill B cells - each recognize a particular epitope - one microbes causes reaction from many B cells which recognize a different part of the microbe - Plasma cells - short lives but produce 2000antibodies/s

Answer 128

- survive more than a decade - linger - speed up response to the same invader - immunization

Answer 129

Antigen dose - if overdose B and T cells overstimulated - T cells non functional - B cells do not respond to subsequent exposures to make antibodies * this is called Anergy - this is why we dont respond to microbes in microbiome (if healthy)

Answer 130

- small - simple - most abundant - monomer - binds 2 - binds complement - 70% total serum Ig - 4 classes vary in aa sequence and interchain crosslinking Jobs: - binds microbes to allow phagocytosis - binds and neutralizes viruses (blocks it from grabbing host) - activates classical complement

Answer 131

- secreted - mucosal surfaces - dimer (disulfide link on joining chain) - binds 2-4 - does not bind complement - 15-20% total serum Ig - secretory piece wrapped around both molecules - found in tears, breast milk

Answer 132

- monomers on B cells - hoe it gets activated by T cells - pentomer held tgt by J protein - binds 2-10 - binds complement - 5-10% total serum Ig - first to be detected during infection bc large and big response

Answer 133

- present in small amounts - monomeric on B cells - binds 2 - does not bind complement - 0.2% total serum Ig - B cell activation - arming basophils and mast cells

Answer 134

- found in trace amounts - on surface of mat and basophil cells - loaded with inflammatory mediator in granules - binds 2 - does not bind complement - 0.002% total serum Ig - when 2 IgE molecules crosslink on a cell they degranulate and quickly amplify immune response - early infection (acute response)

Answer 135

- First encounter - large amounts of allergen IgE made - anti allergen IgE attach to mast cells - Second encounter - crosslinking surface IgE with allergen causes signal cascade to release histamine *epinephrine can prevent degranulation (creating histamine) by increasing cAMP Leukotrienes from eosinophils

Answer 136

- from mast cell degranulation - XS histamine trigger smooth muscle contraction (lungs) - weakens tight junctions btw blood vessel cells - leaking - fluid forced out of circulation into tissue - flid has histamine and rapidly spreads

Answer 137

- C3, C1, C2 - Break down C3 to make C3 convertase - this initiates creation of the membrane attack complex

Answer 138

- lectin produced by liver - binds sugars on bacteria - this allows complement proteins to bind and trigger C3 convertase - same as classical

Answer 139

- virulence strategy changes to avoid immune system - new antibodies not recognized by antibodies and are invisible to cytotoxic T cells - why we need 3 complement pathways eg - meningitis, ghonorrhoeae, Salmonella

Answer 140

1) epithelial barrier with T cells that encounter antigens (intraepithelial lymphocytes) - alert body to pathogens 2) dendritic cells sample gut microbiota 3) M cells (payers patches) sample antigens, small intestine * sample antigens presented to rich supply of macrophages to protect and recognize as self

Answer 141

- coats microbes in gut considered to be threats - prevents them from penetrating the barrier - also may promote the colonization of beneficial microbes by adherence

Answer 142

Positioned into the gut Positioned on basal side - see fewer antigens but more successful ones - thus they are more reactive TLRs - some beneficial microbes dampen TLR signaling

Answer 143

- how well does an antibody recognize and distinguish an antigen - shown by survivors of smallpox eg not getting the disease again

Answer 144

- inoculation (variolation) of cowpox protected against smallpox (edwardEdward Jenner jenner) - There are multiple viruses for one infection (cold) - hard to protect against all of them

Answer 145

Brought variolation to England

Answer 146

after an immune response to an infection the body can better recognize the pathogen and fight it off.

Answer 147

- work because of our adaptive immune response - trick the body into seeing a pathogen and raising an immune response

Answer 148

- kill without damaging the organism P: easy to produce, many antigens presented C: hard to achieve complete deactivation eg: Hep A, early polio vaccine (Salk vaccine) Cutter Incident - Salk vaccine had live viruses - many polio cases

Answer 149

- weaken organism but not killed - strengthen immune system - find and remove what makes it virulent P: pathogens are presented to the right part of the body (eg not arm injection when respiratory virus), many antigens are presented C: hard to produce , hard to find virulence factors, do not give to immunocompromised (they still can't fight it), cold chain distribution eg: BCG (dermal injection), Sabin polio vaccine (oral)

Answer 150

- purified components of pathogens - specific antigens or epitopes - targetted immune response P: easy to produce, no chance of infections C: hard to find a protective antigen eg: Streptococcus pneumoniae capsular antigen, viral capsids from human papillomavirus, toxoid vaccines *to increase efficiency, some include subunits from multiple pathogens

Answer 151

- have mRNA that codes for specific antigen - wrapped in lipid layer and injected - briefly makes target antigen - mRNA has short half life and does not last long - reaction at site P: once set up easy to make, no chance of infections, quick to market C: cold chain distribution, poor understanding eg: Spikevax and Comirnaty against SARS-CoV-2 - upcoming vaccines against Zika virus and influenza

Answer 152

- uses inactivated toxin from a germ to protect from the effects of the actual toxin, not the pathogen itself - Diptheria - Pertussis - Tetanus - Clostridium botulinum

Answer 153

1st response: - Bcells mostly syhtesize IgM (rapid response) - such a rapid response that antigen receptors are not perfect 2nd Response: - Synthesizes more IgG - have better more adjusted receptors

Answer 154

- viruses like the flu change properties - SARS-CoV

Answer 155

- as Tcells and Bcells replicate they may slowly lose specificity - eg tetanus every 10 years

Answer 156

Salk (dead) Sabin (live attenuated) - Polio transmits fecal oral - replicate in gut mucosa - causes viremia (virus in blood) - Salk injected (protects against paralysis but not mucosal response) - Sabin - drops on tongue

Answer 157

A vaccinated person is infected but may not have many symptoms and is still infectious

Answer 158

If majority of population is vaccinated it makes infection harder to spread - protect the immunocompromised that cannot get vaccinated

Answer 159

People thought cowpox would turn them into cows

Answer 160

- rediscovered penicillin

Answer 161

- properties of penicillin mold by watching stable boys who used mold growing on saddles to treat saddle wounds on horses

Answer 162

- purifying penicillin

Answer 163

- Daughter infected after a pin prick - injected her with a dye called prontosil (possible antimicrobial)

Answer 164

Prontosil metabolized to sulfanilamide in body - PABA turns to folic acid in the body (B vitamin) - Sulfanilamide inhibits enzyme to make folic acid interrupting bacterial metabolism - because bacteria make folic acid but humans cant *basis of Salfa drugs

Answer 165

- screened 10,000 strains of soil bacteria for antimicrobial activity (his PhD students) - discovered streptomycin

Answer 166

Serial Dilution in a 96-well plate: - Find the minimum concentration that bacteria do not grow E-strips: - where the tera drop ends is the MIC - only one company makes Kirby-Bauer Disk Diffusion: - test many different antibiotics against one bacteria *time consuming, may not reflect host conditions

Answer 167

- derived from fungi - beta lactam ring and r groups (different properties and range) - penicillin binding proteins (transpeptidases, transglycosylase)

Answer 168

1) Inheritance of genes that produce an enzyme that provides beta lactam resistance (beta lactamase) - beta lactamase (Delhi metallo-beta-lactamase 1 (NDM-1) - can use beta lactamase inhibitors like clavulanic acid 2) Inheritance of gene for an altered PBP that does not bind the antibiotic - MRSA, codes PBP with low affinity for beta lactam antibiotics

Answer 169

- continually altered to counter resistance - usually only used in worst case scenarios (to slow dev of resistance)

Answer 170

- binds bactoprenol lipid carrier - cannot connect peptidoglycan monomer to growth chain - toxic. topical use

Answer 171

- inhibits enzymes that make a precursor peptide of the NAM side chain - treat tuberculosis

Answer 172

- binds to D-ala, D-ala terminal end of the disaccharide and prevents binding of translycosylases and transpeptidases (cant stabalize)

Answer 173

inserts in bacterial membrane

Answer 174

- binds to both inner and outer membrane of G- bacteria - can also affect mammalian membranes

Answer 175

- forms channels in G+ bacterial membranes - effective against MRSA

Answer 176

- interfere with nucleic acid synthesis - prevents THF synthesis - humans use THF to synthesize nucleic acid

Answer 177

- target microbial topoisomerase - dont allow protein to unfold and replicate - they are toxic to mitochondria

Answer 178

- activated by reduction of microbial flavodoxin and ferrodoxin - only in anaerobic environments - cuts DNA at random points - not effective against aerobic bacteria

Answer 179

- inhibit RNA synthesis - does not allow RNA from exiting RNA polymerase - turns body secretions bright orange

Answer 180

- bacterial ribosomes very different to eukaryotic ribosomes - 70S made of 30S and 50S - --S is the sedimentation factor

Answer 181

- binds 16S ribosomal RNA (in 30S) cause misreading of mRNA

Answer 182

- bind and distort ribosomal A site (accepts tRNAs) - interfere with bone development and calcium absorption

Answer 183

- inhibit translocation of growing peptide

Answer 184

- inhibit peptidyltransferase - can depress the production of blood cells in bone marrow in some people

Answer 185

- bind to 23S rRNA component - prevent formation of 70S initiation complex

Answer 186

- bind to peptidyltransferase site - usually 2 types act together

Answer 187

- binds to bacterial enzymes that attach aa to tRNA molecules - stop protein synthesis - used topically to treat G+ infections - CANNOT be used internally - rapidly degraded in bloodstream

Answer 188

- consistent high use of antibiotics - exerting selective pressures on bacteria to evolve

Answer 189

- modify target (shape of PBPs or ribosomal proteins) - Add modifying group to inactivate antibiotic (aminoglycoside resistance)

Answer 190

- destroy antibiotic before entering cell (beta-lactamases) - decrease membrane permeability - narrow pores (fluoroquinolone resistance) - pump antibiotic out with transporters (tetracycline resistance)

Answer 191

- ribosomes protect and rescue - G+ bacteria make prots to prevent or dislodge binding of antibiotics near peptidyltransferase site

Answer 192

- A built in natural resistance - eg G- bacteria cell walls block antibiotics

Answer 193

Mutation - selection Vertical Transmission - to daughter cells Horizontal Transmission - to other cells

Answer 194

- in soil and in the amazon forest type environment

Answer 195

- too much antibiotic use in the golden age - too much antibiotics in agriculture - antibiotics take and prescribed inappropriately - if you take antibiotics for less than the required time it doesnt kill the microbe and they may become resistant - bacteria is often in biofilms where resistant strains persist - pharma companies do not develop new antibiotics (too expensive)

Answer 196

negative strand RNA virus - group 5

Answer 197

- the common flu - 10% of america and canada each year - pregnant women and elderly most susceptible - binds to sialic acid glycoprotein on host epithelial cells (lungs/intestines)

Answer 198

- narrow host range - serious disease but mutates slowly

Answer 199

- narrow host range - mild disease - hard to spread

Answer 200

- never detected in humans - associated with swine and cattle - rare

Answer 201

- H1N1 - extremely infectious but mild - H7N9 - serious disease but not as infectious - only transmitted bird to person currently (a future strain connecting the two would be very dangerous)

Answer 202

- flu is long lasting, cold is shorter - cold often has no fever - cold no exhaustion *"stomach-flu" - gastroenteritis

Answer 203

- no geometrical capsid - shell of matrix proteins (M1) surrounding 8 chromosome fragments - HA and NA on surface of protein

Answer 204

- blocks NA activity

Answer 205

- 8 RNA fragments coated with nucleocapsid protein - each encodes 1 protein - just enough to replicate - each packages with RNA-dependent RNA polymerase to start replicating immediately - when packaged they line up like a bundle of sticks - each host can produce 10,000 virions

Answer 206

- allows it to change its antigenic determinants - evades host acquired immunity - when segmented can reassort genetic material and drastically change strains quickly

Answer 207

- 18HA subtypes - attaches host cell - cell membrane fusion - c terminal trimer complex with a N terminal fusion peptide 1) HA c terminal domain binds to sialic acid receptor 2) virion uptake via endocytosis 3) endocytic vesicle acidifies and changes conformation to brings N terminal fusion peptide close to viral membrane 4) they fuse tgt 5) this releases genome into host cytosol

Answer 208

- avian natural reservoir for influenza A - susceptibility requires a host cell protease to cleave HA and initiate infection - also depends on host cell surface (can they bind) - differences in sialic acid btw birds and human - different susceptibility - pigs have both types of receptors (if they get infected with two strains they can reassort and potentially combine)

Answer 209

- 11 N variants - within the membrane envelope proteins assembled around the genome and matrix proteins - virions bud ut the host - neuraminidases cut virion loose from host glycoproteins to release them

Answer 210

- the ability of flu virus to mutate and change slightly - usually because of RNA replication errors in HA and NA genes

Answer 211

- a big change in the structure of the flu virus - like jumping of the virus to a new species - reassortment of the genes from two viruses in a single host (pig)

Micro 2420 Second Half Flashcards

Discover all of the bacteria in the world in my own research lab that I pay for with the money I make from selling cookies :) (235 cards)