Hi Shawn, we chose a lytic phage because in phage therapy, lytic phages are almost always required, as temperate phages form lysogens. Lysogens are bacteria with viral DNA incorporated into their own, and they express immunity to subsequent infections from viruses of the same cluster.
Hi Emma! Yes, temperate phages are able to undergo either life cycle. If the conditions of the host bacteria are unfavorable (i.e. the bacteria is under some kind of stress), temperate phages will undergo the lytic cycle. If the bacterial host is under favorable conditions, the phage will incorporate its DNA and remain dormant until the conditions change.
Hi Zach, yes, lytic phages are much more valuable in phage therapy, as they do not form lysogens with immunity to further phage infections. This being said, sometimes temperate phages are genetically modified and used in therapy, such that they can only undergo the lytic cycle.
If you were to isolate a temperate phage (and had not isolated a lytic phage that you could choose) is there something you can do to alter the temperate phage and give it lytic abilities?
Hi Eva! Yes, we could use genetic modification to disable the temperate phage from undergoing the lysogenic life cycle, although that is beyond the scope of this lab. It has been successfully done and used in treatment by phage therapy researchers, though!
Do you think that there might have been a possible cross contamination that resulted in both a temperate phage and a lytic phage appearing on the plaque assay?
Hi Jolaya! The presence of two phage species at that point in the experiment was likely not due to contamination. Rather, the initial sample that we created a lysate from had not yet been purified, so there were probably many species of phage in the sample.
There are many ways phages can be administered, it really depends on the type of bacterial infection that needs to be treated. They can be administered locally to an infected wound, intravenously, or orally.
Why did you choose the lytic phage over the temperate phage?
Hi Shawn, we chose a lytic phage because in phage therapy, lytic phages are almost always required, as temperate phages form lysogens. Lysogens are bacteria with viral DNA incorporated into their own, and they express immunity to subsequent infections from viruses of the same cluster.
Can a phage possess behavior from both lytic and lysogenic cycles? Great presentation!
Hi Emma! Yes, temperate phages are able to undergo either life cycle. If the conditions of the host bacteria are unfavorable (i.e. the bacteria is under some kind of stress), temperate phages will undergo the lytic cycle. If the bacterial host is under favorable conditions, the phage will incorporate its DNA and remain dormant until the conditions change.
Is there any value, clinically, for a lytic phage to be used rather than a temperate?
Hi Zach, yes, lytic phages are much more valuable in phage therapy, as they do not form lysogens with immunity to further phage infections. This being said, sometimes temperate phages are genetically modified and used in therapy, such that they can only undergo the lytic cycle.
If you were to isolate a temperate phage (and had not isolated a lytic phage that you could choose) is there something you can do to alter the temperate phage and give it lytic abilities?
Hi Eva! Yes, we could use genetic modification to disable the temperate phage from undergoing the lysogenic life cycle, although that is beyond the scope of this lab. It has been successfully done and used in treatment by phage therapy researchers, though!
Do you think that there might have been a possible cross contamination that resulted in both a temperate phage and a lytic phage appearing on the plaque assay?
Hi Jolaya! The presence of two phage species at that point in the experiment was likely not due to contamination. Rather, the initial sample that we created a lysate from had not yet been purified, so there were probably many species of phage in the sample.
How would phages be administered in a clinical setting?
There are many ways phages can be administered, it really depends on the type of bacterial infection that needs to be treated. They can be administered locally to an infected wound, intravenously, or orally.