Term
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Definition
| NOT EXTREME, presence can be considered extreme |
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Term
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Definition
– Live at temp between 15-45 °C
– most bacteria; salmonella, staph all live on humans and live at our temps
– most pathogens |
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Term
| – Psychrophiles (Cryophiles) |
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Definition
– ~15 °C or less optimum
– fluid (flexible unsaturated membranes
– flexible proteins |
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Term
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Definition
– 55-70 °C optimum
– pcr enzymes bc they work at high temps |
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Term
| – Hyperthermophiles (extreme thermophiles) |
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Definition
– 80 °C+ optimum
– Crosslinked saturated membranes
– Ether membrane structures instead of esters bc stronger bonds needed for high temps
– Rigid proteins
– Strain 121 (Geogemma barossii) *** know this
– 107 C to 121, like high temps, high pressure to evoid boiling |
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Term
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Definition
| plasmolysis: membrane/wall separate. |
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Term
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Definition
| – Cells lyse. Bacteria with cell wall gives it some protection but if theres enough salt causes plasmolysis-> cell wall comes apart from membrane causing burst |
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Term
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Definition
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Term
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Definition
– Not extremophiles
– Ex staphylococcus aureus lives on skin: 10% NaCl OK sweating causes salt on skin but this microbe can survive the high salt on skin
– Don’t like it but can TOLERATE it |
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Term
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Definition
3%+ NaCl
– Oceans/ a lot of marine bacteria . Will die w/out NaCl |
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Term
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Definition
10-20% NaCl
– (great salt lake, dead sea, deep sea vents) |
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Term
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Definition
| – Considered normal: pH 5-8 optimum is 7, most bacteria |
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Term
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Definition
– pH<5
– ex: lactobacillus acidophilus (purple G+) pH 4, regulate proton gradient allows them to survive these conditions. |
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Term
| – Alkaliphiles (alkalophiles)– |
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Definition
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Term
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Definition
Energy production with or without O2
• Aerobic respiration: O2 terminal electron acceptor
Oxygen is not organic
• Anaerobic respiration: Other inorganic terminal electron acceptor
• Fermentation: Organic terminal electron acceptor (carbons and H+) |
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Term
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Definition
| • Strict aerobes, facultative anaerobes, microaerophiles, aerotolerant anaerobes, obligate anaerobes |
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Term
"use of oxygen" obtains energy from --
removes-- |
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Definition
source (light, inorganic, and/or organic compounds)
electrons from chemical compounds,
– Eventually transferring them to terminal electron acceptors which leave the celll and or are used for other purposes
– pyruvate |
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Term
| use of oxygen mechanisms are used by all microbes? |
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Definition
| – Some microbes use only one mechanism; others may do all 3. |
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Term
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Definition
| – Use an electron transport system/chain (ETS/ETC) to make proton motive force (PMF) |
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Term
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Definition
series of proteins and small molecules
– Bonds are broken when electrons transferred between ETS/ETC components
– Energy from bond-breaking pumps H+
– PMF= [H+] outside > [H+] inside membrane |
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Term
| – Alternative to respiration= |
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Definition
Fermentation – No ETS/ETC
– Might be genetic or environmental thing |
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Term
| – ATP (adenosine triphosphate) synthase uses energy stored in |
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Definition
| – Oxidative phosphorylation |
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Term
| 3 mechanisms for use of oxygen |
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Definition
aerobic- best
anaerobic
fermentaion-worst |
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Term
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Definition
– Electrons donated to inorganic terminal (final) electron acceptor 02 (o2 is reduced)
– Oxygen dependent
– Most efficient (most ATP)
– Final product= water |
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Term
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Definition
– Electrons donated to DIFFERENT inorganic terminal electron acceptors (NO3-, SO4-2, others)
– Oxygen independent
– Less effecient than aerobic respiration
– Final product: No2-, other inorganics |
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Term
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Definition
– No ETS/ETC (other proteins/enzymes involved)
– No H+ pumped, no ATP synthase
– Most inefficient : no (or very little) ATP produced
– Only substrate level phosphorylation
– Oxygen-independent
– Electrons donated to organic terminal electron acceptor (pyruvate c3H4o3
– Final product organics and or CO2
– Lactic acid |
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Term
| Is oxygen on its own toxic? |
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Definition
| No but it has toxic byproducts |
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Term
Toxic by products of O2=
1.
2.
3. |
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Definition
= “oxidative stress”
– O2 ·- radical (superoxide) radical
– H2O2 (hydrogen peroxide)
– HO· radical (hydroxyl) – reacts FAST |
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Term
| Detoxification from O2 is by: |
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Definition
3 enzymes
SOD
Catalase, peroxidase |
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Term
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Definition
| superoxide dimutase consume superoxide radical but generates peroide (also toxic) Adds H+ |
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Term
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Definition
| consumes peroxide: turns peroxide into water and oxygen. o2 and H20 can diffuse out freely |
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Term
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Definition
-SOD and catalase/peroxidase
Req )2
Only aerobically ALWAYS NEED O2, always need those enzymes around to get rid of radicals.
Cant respire anaerobically, cant ferment
Ex: mycobacterium tuberculosis many cyanobacteria (anabaenous spiroidis), neisseria gonorrheae |
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Term
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Definition
– Facultative anaerobe
– -sod and catalase/peroxidaze
– prefers to respire aerobically
– back up plan: respires anaerobically and/or ferments
– No o2- can still survive
– ex: salmonella typhimurium |
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Term
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Definition
grow better with o2
SOD and catalase/peroxidase enzymes => can deal with reactive oxygen species
Doesn’t care about 02, not efficient at getting energy out of environment
Cannot respire and only ferments= obligate fermenters
Ex: Lactobacillus acidophilus, Streptococcus pyogenes |
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Term
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Definition
Very little SOD and catalase/peroxidase
Req low (2-10%) levels of O2
Higher O2 levels toxic
Usually respire aerobically
Ex: Treponema pallidium |
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Term
| – Strict (obligate) anaerobe |
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Definition
No SOD, catalase, peroxidase, O2 is toxic
Respire anaerobically and/or ferment
Do not respire aerobically
EX: clostridium perfringens |
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