Yes! A PCR is used to amplify sequences of DNA by putting the DNA through a machine that changes temperature many times, in order to separate the DNA and make copies of it. The point of this was to test if our DNA had the sequence that our predicted cluster phage DNA had, in order to confirm whether or not it was in this hypothesized cluster. If a band appeared on the gel it meant that the sequence of DNA we were looking for was in fact amplified, meaning that our phage was a part of that cluster. When we tested the k cluster on our DNA, no band appeared, meaning that our cluster hypothesis was incorrect.
Yes, this is possible, although not exactly preferred. They are specific in that they target specific receptors on bacteria, and can only bind to their complementary receptor. Some phages can infect multiple types of bacteria, and are described as having a wide host range. However, the main attraction of phages is that they are specific to one type of bacteria, and that they will only kill the harmful bacteria rather than all of the bacteria in the body. This is why they are a safer alternative to antibiotics.
Good question! It has been shown that administering effective antibiotics promptly after infection has a much higher success rate as well compared to waiting for the infection to develop before administering the antibiotics. Phages operate in the same way in this case: they wipe out the bacteria before they’re able to further proliferate, so time is of essence here.
Yes, temperate phages can be used, but they must first be modified into lytic phages. Sometimes, a temperate phage is the perfect candidate for phage therapy (targeting the specific harmful bacteria that is being tested) so it is then modified by removing the repressor proteins that prevent it from undergoing the lytic cycle, and removing the enzyme integrase that integrates the phage DNA into the host genome. After modifications have been made it now lyses all of the cells, rather than previously lysing some and integrating into some (leaving the bacterial cells alive).
You mention survival was much higher using a combination of phages. Does the order in which phages are received matter? Meaning, would survival be higher by receiving phage 1 and then phage 2, or vice-versa?
So when multiple phages are combined, it’s called a phage cocktail (a mixture of phages). This is very common in phage therapy; because the phage is so specific, sometimes it can’t reach all of the harmful bacterial cells, and multiple phages are needed to lyse all of the harmful bacteria. In this study, the phage were mixed together and administered at the same time, not one after the other.
curesymposium.org 
Can explain what PCRs are used for/how they work?
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Yes! A PCR is used to amplify sequences of DNA by putting the DNA through a machine that changes temperature many times, in order to separate the DNA and make copies of it. The point of this was to test if our DNA had the sequence that our predicted cluster phage DNA had, in order to confirm whether or not it was in this hypothesized cluster. If a band appeared on the gel it meant that the sequence of DNA we were looking for was in fact amplified, meaning that our phage was a part of that cluster. When we tested the k cluster on our DNA, no band appeared, meaning that our cluster hypothesis was incorrect.
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Is it possible for a phage to target multiple bacterial species?
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Yes, this is possible, although not exactly preferred. They are specific in that they target specific receptors on bacteria, and can only bind to their complementary receptor. Some phages can infect multiple types of bacteria, and are described as having a wide host range. However, the main attraction of phages is that they are specific to one type of bacteria, and that they will only kill the harmful bacteria rather than all of the bacteria in the body. This is why they are a safer alternative to antibiotics.
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Why do you think the mice survived more when treated with the phage after 1 hour than when they were treated 8 or 24 hours after infection?
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Good question! It has been shown that administering effective antibiotics promptly after infection has a much higher success rate as well compared to waiting for the infection to develop before administering the antibiotics. Phages operate in the same way in this case: they wipe out the bacteria before they’re able to further proliferate, so time is of essence here.
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Do you know if a temperate phage has ever been used for phage therapy or is it strictly lytic phage as of right now?
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Yes, temperate phages can be used, but they must first be modified into lytic phages. Sometimes, a temperate phage is the perfect candidate for phage therapy (targeting the specific harmful bacteria that is being tested) so it is then modified by removing the repressor proteins that prevent it from undergoing the lytic cycle, and removing the enzyme integrase that integrates the phage DNA into the host genome. After modifications have been made it now lyses all of the cells, rather than previously lysing some and integrating into some (leaving the bacterial cells alive).
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You mention survival was much higher using a combination of phages. Does the order in which phages are received matter? Meaning, would survival be higher by receiving phage 1 and then phage 2, or vice-versa?
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So when multiple phages are combined, it’s called a phage cocktail (a mixture of phages). This is very common in phage therapy; because the phage is so specific, sometimes it can’t reach all of the harmful bacterial cells, and multiple phages are needed to lyse all of the harmful bacteria. In this study, the phage were mixed together and administered at the same time, not one after the other.
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