Lecture 15 Flashcards
Why do cells need iron
-Electron transport chain
-helps transfer electrons since they can bind to iron
TonB
Found in outer membrane, transports iron & other trace elements
How do bacteria acquire iron?
Siderophores
What are siderophores
proteins used to get iron
Lipocalin 2
When gut is inflamed, lipocalin 2 will inhibit enterobactin
Why is iron a limiting agent
Iron is a limiting agent in bacteria cells because it is an essential nutrient for their growth and survival, but it is often scarce in the environment and tightly regulated by the host, making it challenging for bacteria to acquire sufficient iron for their needs.
How does E.coli Nissle outcompete Salmonella?
E.coli Nissle outcompetes Salmonella by using a similar mechanism to acquire iron that is not inhibited by lipocalin 2
-uses salmochelin as well but has other siderophores that Salmonella does not
How does fermentation relate to glycolysis
Fermentation maintains NAD+ level for glycolysis
True or false: Fermentation relies on respiration
False
-Fermentation has nothing to do with respiration, only makes NAD+ for glycolysis
Homolactic fermentation
Leads to production of ONE fermentation product which is LACTATE
-also makes NAD+
-yogurt
Heterolactic fermentation
Leads to production of MORE products
-Lactate, ethanol, and CO2
-also makes NAD+
-sauerkraut, silage, kefir, kimchi
What products do homolactic fermentation make
Lactate
What products do heterolactic fermentation make?
Lactate, ethanol, and CO2
How can lactic acid cause cavities?
A biofilm will form on teeth
-inside biofilm there is intracellular polysaccharide (glycogen) that is not actively diving so it goes through glycolysis
-streptococcus mútanos goes through fermentation
-Lactic acid fermentation can cause an acidic environment in the mouth which will demineralize the teeth and cause cavities
Does fermentation require oxygen?
Fermentation does not require oxygen but can also do fermentation if oxygen is present
True or false: All microbes utilize glycolysis
False
-Some microbes use the Entner-Doudoroff pathway instead pf glycolysis
What is the Entner-Doudoroff pathway?
Combines the pentose phosphate and glycolic pathway
-Makes 1 ATP instead of 2 like glycolysis
-Makes NADPH and NADH
What is the Pasteur effect?
-Oxygen inhibits fermentation
-With oxygen: bacteria consumes less glucose
-Without oxygen: consumes more glucose
Why is industrial alcohol production kept in anaerobic conditions?
-Anaerobic conditions forces the facultative anaerobes to choose the fermentation pathway instead of aerobic respiration
-With O2 no alcohol is made
-Without consumes more glucose, sugars are converted into ethanol and CO2
True or false: with oxygen facultative anaerobes consume more glucose
False
In aerobic (w/ oxygen) condition facultativos anaerobes will consume LESS glucose
True or false: without O2 facultative anaerobes consume more glucose
True
In anaerobic conditions that facultative anaerobes consume MORE glucose
