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TOXINS Study Guide Flashcards

1
Q

Toxoid

A

Altered or inactivated toxin. Either by heat or chemical means.

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2
Q

Toxemia

A

The presence of toxin in blood.

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3
Q

Antitoxin

A

Usually an antibody proteins that binds to toxin.

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4
Q

Why individuals need to be given toxoid despite the fact the body makes antitoxins.

A

Because it is used as vaccines to stimulate immune system.

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5
Q

Exotoxin

A

Synthesized and secreted by gram (+) (-) be bacteria; part of their normal growth and metabolism coded by plasmids or phage DNA( mainly)

Cytotoxin
Neurotoxin
Enterotoxin

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6
Q

Exotoxin

                 CYTOXIN
A

Kills/ affects host cell function

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7
Q

Exotoxin

                 NEUROTOXIN
A

Impairs neuronal cells, function; causes paralysis.

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8
Q

Exotoxin

                    Enterotoxin
A

Alters functioning of the gastrointestinal cell lining, causes intestinal disturbances.

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9
Q

Endotoxin

A

Lipid A portion of outer membrane LPS of gram negative sps.

Released upon cell damage and cell wall breakage.

All endotoxins produce the same signs and symptoms, through to different degree.

Symptoms include dilation of blood vessels, drop in blood pressure.

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10
Q

Toxins

A

Harmful substances made by some pathogenic bacteria species. Cause tissue injury/ trigger host immune response

Normally blood or lymph soluble.

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11
Q

Endotoxin and exotoxins in relation to:

Source, relative toxicity, stability and effect in host.

A

Exotoxin:

Source: gram(-) and positive

Relative
Toxicity: high

Heat stability; unstable at high temp

Effect on host: variable

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12
Q

Endotoxin

A

Source: gram (-)

Relative
Toxicity: low

Heat stability: stable @1hr, 120 c

Effect on host: fever, shock,coagulation

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13
Q

Exotoxins are made by gram(-) and (+) bacteria.

A

There are both gram (+) and (-) exotoxins

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14
Q

Identify the various cytotoxins discussed in class.

A

Hemolysin toxin

Diptheria toxin

Anthrax toxin

Shiga toxin

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15
Q

Anthrax toxin:

A

(PA)- protective antigen

(LF)-Lethal factor

(EF)- edema factor

Anthrax toxin allows the bacteria to engage the immune system, proliferate, and ultimately kill the host animal.

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16
Q

Is the anthrax toxin chromosomally coded or plasmid coded?

A

Virulent strains of B anthrax contain 2 large plasmids

1-plasmid encodes the three secretory toxins produced by the bacteria.

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17
Q

Exotoxin:

                Shiga Toxin
A

Potent cytotoxin made by Ecoli 0157H7

A part enters ->endothelial cells->reacts with-> ribosomes->Stops->protein synthesis

Also responsible for hemolytic uremic syndrome.

RBC-> break up-> in tiny blood vessels->results in-> anemia, kidney failure, accompanied by paralysis and nervous system injury signs.

Avoids immune system to one cell to another. Gram negative

Bloody stool

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18
Q

Exotoxin:

                  Diptheria
A

Is an exotoxin secreted by corynebacterium diptheriae, the pathogen bacterium that causes Diptheria.

The toxin causes the disease Diptheria in humans by gaining by entry unto the cell cytoplasm and inhibiting protein synthesis.

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19
Q

How do Diptheria toxin get inside cells?

A

Consists of 2 polypeptides

One polypeptide binds to human growth factor on many types of human cells, triggering endocytosis of the toxin.

Once inside the cell, proteolytic enzymes split the toxin molecule, releasing the second toxin polypeptide into the cytosol.

This polypeptide enzymatically destroys a eukaryotic elongation factor- protein required for translation of polypeptides.

Because the action of the toxin is enzymatic, a single molecule of toxin sequent lay destroys every molecule of elongation factor in a cell, completely blocking all polypeptide sythesis and resulting in cell death.

Diptheria toxin is thus one of the more potent toxins known.

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20
Q

Neurotoxins target

A

Neurotoxin impairs neuronal cells function: causes paralysis.

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21
Q

Neurotoxins are:

A

Botulism toxin

Tetanus

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22
Q

Botulism toxin

A

Toxin belongs to AB- B attached to specific receptor on motor nerve endings

Toxin A- part enters inside, becomes an active peptidade enzyme that degrades a vesicles protein that’s responsible for attachment to cytoplasmic membrane.

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23
Q

Tetanus toxin

A

Is another disease caused by neurotoxin produced by a species of Clostridium.

Causes prolonged muscular contractions

Complete, unrelenting contraction of the diaphragm results in final inhalation- patients die because they cannot exhale.

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24
Q

Hypokalemia

A

Loss of water-> lower blood volume due to water loss-> compromises vital organ functioning->

These conditions can produce muscle cramping, lethargy( tiredness), sicken eyes, heartbeat irregularities,kidney failure, coma, and death.

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25
Mycoplasm pneumonia
Strictly aerobic encapsulated mycoplasma Pleomorphic Lipid in cytoplasmic membranes called sterols A feature lacking in other prokaryotes Contain both RNA and DNA Binary fusion Gram positive Lack cell walls M. Pneumonia attach to cilia causing it to stop moving up mucus Bacteria stays in mucus Close contact it spreads dormitory residents Treated with erythromycin or tetracycline Frequent hand washing No vaccine Smallest form of life- can squeeze through filters Fried egg appearance Mild symptoms Persistent unproductive cough Penicillin is not effective
26
Pneumonia virulence
- capsule ->can protect cells from phagocytosis | - adhesive protein-> is bacteria cell to attach to receptors on the epithelial cell
27
Chlamydia
- sexually transmitted disease - RNA and DNA - non motile and multiply w/in cells - gram (-)be bacterium, surround each chlamydial cell, but there is no peptidoglycan between membranes - no cell wall - transmitted by medical instruments and swimming pools. - non- motile - hides in sperm cells
28
Chlamydia antibiotics
Tetracycline and urthromysin Then they target bacteria Ribosomes and protein synthesis
29
Chlamydia-STD
Sexually transmitted disease: 1. non gonococcal urethritis - similar, but minor than Gonnorea - a symptomatic, common in woman and complication is PID- pelvic inflammatory disease/ immune response towards infected cells. Men's symptomatic- urthirtus painful urination pus and discharge from penis.
30
bubos- chlamydia
Infection of the lymph nodes painful inflamed lymph nodes.
31
Ocular disease:
Conjunctivitis trachoma. | - non traumatic blindness in children's
32
STD
Lymphogranaloma vererum which is characterized by transient genital lesion at the site of infection on the penis, urethra, scrotum, vagina, cervix, or external female genitalia.
33
Chlamydia
Binds to conjunctival cells and multiplies within: killing them Triggers- pus formation Scars- conjunctiva Inturn patients- eyelids turn inwards Eyelashes irritates, scratches and scars cornea Triggers- blood vessels invasion into clear areas; looses transparency Leads to- blindness
34
Cellular morphologies
Elementary bodies - small, cocci shaped - infective form; dormant and similar to spores in resistance - extra cellular form - reticulate bodies - large, pleomorhic - reproductive forms - intracellular form
35
Rickettsia
Causes Rocky Mountain spotted fever and transmitted by tick. Spotted rash on trunks, appendages, palms and soles along with fever, headache, chills, muscle aches May involve the resp, GI and nervous system; CNS infection may induce convulsions, coma and death.
36
Rickettsia rickettsii
Non motile Gram (-)be aerobic intercellular parasite Unlike chlamydial, has a peptidoglycan cell wall and lipopolysaccharide outer membrane; slime layer is also present Outside host dies quickly; needs transmission from one host to another Fragile bacteria Enters host cell by endocytosis and excited cells by exocytosis Prevents vehicle fusion with lysosomes to form phagosomes; breaks out of vehicle by enzyme secretion Slow growing pathogen and divided only 8-12 hrs. The bacteria remains dormant in ticks salary gland; prolonged feeding makes infective bacteria release into host system Does not make any toxin the damage is often due to break down of blood vessels Low blood pressure and insufficient nutrient and oxygen delivered to the body.
37
Are the anthrax toxin individual sub units?
No they are not.
38
Diptheria and its action
It's an exotoxin secreted by corynebacterium diptheriae, the pathogen bacterium that causes Diptheria. The toxin causes the disease Diptheria in humans by gaining entry into the cell cytoplasm and inhibiting protein synthesis. 2 sub units A-B
39
Diptheria
Pleomorhic Non endospores forming Gram positive Colonizing the skin and respitory, gastrointestinal, urinary, and genital tract. Is transmitted from person to person via respitory droplets or skin contact. Poorer parts of the world that lack adequate immunization. Individuals are symptomatic Infections in immunocompromised individuals result in mild respitory disease. Loeffler's medium used for Diptheria Treatment-administration of antitoxin- to neutralize Diptheria toxin before it binds to the cell. Penicillin or enthromycin kills Cornebacterium, preventing the synthesis of more toxin. Prevention starts with immunization DYaP
40
Streptococcus pneumonia
Pneumococcal pneumonia is usually lobar Affecting one or more lobes of the lungs Signs and symptoms- fever, chills, congestion, cough, chest pain, which results in short and rapid breathing, nausea and vomiting Blood frequently enters the lungs, causing coughed up sputum Gram positive Normal member of the microbiota of the mouths and pharyngeal of 75% of humans without causing harm. Known as pneumococcus- short chains Secretes a cytotoxin called- pneumolysin which binds to cholesterol in the in the cytoplasmic membranes of the ciliates epithelial cells, producing trans membrane pores that result in the lysis of the cells. Are inhaled occasionally from the pharynx into lungs S. Pneumonia can pass into the blood and brain to cause bacteremia and meningitis Damage lining of alveoli allowing erythocytes, leukocyte a, and blood plasma to enter into the lungs The fluid fills alveoli reducing the ability to transfer oxygen and causing the pneumonia. Cephalosporin,erythromycin,and chloramphenicol are effective alternatives.
41
Tetnus neurotoxin
GAVA Inhibitors Can't relax muscle
42
Botulism
Acitiory Does not contract
43
Action of endotoxin
Lipid A portion of outer membrane LP of gram negative sps. Released upon cell damage and cell wall breakage- MAC and antibiotics All endotoxins produce the same signs and symptoms, though to different degree
44
Anthrax
Coded by plasmids
45
Diptheria
Is coded by chromosomal DNA
46
Botulism
Enzymatic property
47
How are toxins grouped based upon structure?
AB sub units
48
Do the toxin ( botulism) toxin has any peptidade activity and the role.
Yes it does, when it enters in the cell the cell its part A turns into peptidase.
49
Role of SNARE proteins
Facilitates fusion of target and vesicle membrane.
50
COX enzyme
Is for the conversion for arantonic acid and catalizes to prostoglandin
51
Action of Tylenol
Tylenol inhibits COX 3 and acradonic acid is not converted into prostoglandin so you do not get a fever.
52
How are prostaglandins formed
At aracadonic acid are fatty acids formed in the brain and the prostaglandins are produced following oxidation of aracadonic acid COC enzyme is the catalyst for conversion of aracadonic acid to prostaglandin
53
Chlamydial
Gram negative NO CELL WALL
54
Chlamydia- ocular diseases:
Conjunctivitis trachoma | inclusion trachomatis
55
Chlamydia-
Lesions in lymph nodes at the groin are "Bubos"
56
Diptheria
Thus the polypeptide enzymatically destroys a eukaryotic elongation factor - a protein required for translation of polypeptides. Because the action of the toxin is enzymatic, a single molecule of toxin sequentially destroys every molecule of elongation factor in a cell, completly blocking all polypeptide sythesis and resulting in cell death.
57
Gram negative
Diptheria, chlamydia, rickettsia
58
Diptheria
Person to person/ skin contact A symptomatic Gram positive Targets protein sythesis
59
Cholara
02 El Tor is responsible for the pandemics, but new strains 0139 Bengal Causing disease Choleria toxin Coded by plasmid
60
Chlymidea
EB- elementary bodies RT- reticulate bodies
61
Cholerea
Contaminated water and raw under cooked sea food
62
Prevention of Cholerea
Boil water, eat only cooked foods Avoid raw vestibibles and fruit Wash hands
63
Shiga toxin
Poor sewage Inhibits protein sythesis Kills cells Cause kidney failed Attached to surface of neutrophils and is spread by them throughout the body, causing widespread death of host cells and tissues. Antimicribial drugs induce E. Coli O257:h7 to increase its production of Shiga- like toxin, worsening the disease. 50% of beef carcasses in the U.S.
64
Bio films
Regular household Shower curtain, toilet bowl, kitchen sink Industry: microbes accumulation in pipes, drains and cooling towers Beneficial as in bio mediation : microbial mediated Degradation can be enhanced by biofilms Nature: Nature:slipperiness of rocks
65
Biofilms
Biofilms develops as a matrix which allows cells as well as the biofilm to attach Matrix is made of, - DNA - proteins - fibers of glycocalyces Biofilms with associated matrix protects members from environmental stress.(uv radiation), antimicribial drugs, pH alterations, temperature and humidity changes. Concentrate and conserve digestive enzymes
66
Quorum sensing and biofilms
Quorum sensing is the communication between members - cells respond to the neighboring cell's density and secrets molecules.
67
Biofilms
Develope an extra cellular matrix, composed of DNA, proteins,and primarily the tangled fibers of polysaccharides of the cells glycocalyces.
68
Biofilm
Receptor blocking drugs have successfully blocked biofilm formation and prevented disease in mice and are being considered for use in humans
69
Biofilms
Cause up to 70% of bacterial disease in industries countries
70
Biofilm
Cause prostatitis, kidney infections, tooth and gum decay Cystic fibrosis, and infections associated with implantation of medical devise.
71
Rickettsia
Non- motile, gram negative Peptidoglycan wall And lipopolysaccharide
72
Dermacentor
Transmitted by tick
73
Rickettsia
Convulsions, coma and death Enters and exits cells by endocytosis and exits cells by exocytosis. Does not make any toxin
74
Relationship amongst organism
Antagonistic (harmful) Synergistic ( beneficial)- symbiotic- Complex Symbiotic relationship: organisms lives in close contact(physically or nutritional) Complex; Biofilms are cooperative; benefits are amplified - many bacterial diseases are due to this kind of relationship. Ex: microbes of different species are attached to tooth surface, mucous membrane of intestine and other body areas.
75
Lag phase
- no appreciable change in cell number; extend from few hours to few days - cells exhibits intense metabolic activity increased sythesis of proteins, cell wall component Phospholipids Protein synthesizing machinery- Exhibits maximal activity C in media from glucose to lactose-
76
Log phase
- period of rapid growth at exponential rate. - cells are metabolically active; cells divide at constant rate Generation time- tuberculosis drug needs to be taken for a long time to target Micolic synthasis - medically important because drugs have more of an impact on the bacterial growth. They are more sensitive. - plot is a straight line; cells in mid exponential phase are valuable for researchers.
77
Chemostat
Apparatus that keeps the cells in the log phase of growth. ( maintains the cells in the log phase) - inlate valve - fresh medium - outlet valve- dead cells and used
78
Stationary phase
- growth rate slows; new cells produced at the same rate a sold cells die Limited resources 1. Consumption of essential nutrients 2. Waste products accumulation at toxic level 3. pH changes
79
Death phase
- population enters this phase when dying exceeds number of new, viable cells - progressive in some; alternately called as the logarithmic decline phase - continues until small proportion of the cells remain or population dies out entirely - endospores are formed
80
Nutrient uptake
Passive process-substance movement is from high consent ration to a region of low concentration - no expenditure of cellular energy Active/ functions when bacteria are low in nutrient environment - there is expend entire of cellular energy
81
Active transport
Involves substance movement from outside to inside Against conc gradient - substance that cross membrane is not altered
82
Group translocation
Cells picks up substance even though they are in lower cincentration outside -substance altered during transport: prevents from leaving cell Ex: glucose utilization by the phosphor transferase system purine Pyramided and long chain fatty acids transport
83
Rickettsias
Cultivated in eggs
84
Chlamydia
Birds eggs
85
Treponema
Testicle of rabbit
86
Nitrogen
Used for back bone in prodigy an sythesis. Emine group for emio acids.
87
Phosphorous
Phospholipid/ phosphorlization in ATP
88
Sulfur
Proteins for electron transport chain. Amino acid sulfer containing amino. Trace- iron/ zinc/ copper/ cobalt/ manganese
89
Alpha hemolysis
Incomplete destruction
90
Beta hemolysis
Complete destruction
91
Gamma
Streptococcus - no defect on the red blood cells
92
Growth factors
The necessary organic chemicals are called growth factors. Vitamins are growth factors Iron is essential element for the growth and development of all the scale of living organisms.
93
Iron
Oxygen transport, ATP generation, cell growth and proliferation, and detoxification.
94
Autotrophs
They feed themselves Make organic compounds from co2 and thus need not make it from other organisms.
95
Toxic forms of O2
Singlet 02- Molecular oxygen with electrons that have been boosted to a higher energy state, typically. Very reactive
96
Superoxide radical
A few superoxide radicals from during the incomplete reduction of O2 during electron transport in aerobes.they are so toxic that aerobic organisms must produce enzymes called super oxide did mutates to detoxify them.
97
Hydroxyl radicle-(oh)
Results from ionizing radiation and from the incomplete reduction of hydrogen peroxide.
98
Peroxide anion
Hydrogen peroxide formed during reactions catalizes by superoxide dismisses contains peroxide anion, another highly reactive oxidant.
99
The types of anaerobic media
Non-selective blood agar medium And gas pack medium
100
Defined medium
Known
101
Complex
Unknown
102
Enrichment media
Low level to detectable level

Microbiology (19 decks)

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