3.1.07 - 3.1.2007 Generalize vs specialized refer to what...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
3.1.2007 Generalize vs. specialized refer to what genes can be transduced Generalized can be any gene because any gene can happen to be on the fragment that is right size to be packaged into the capsid Specialized: since phage lambda can only integrate part of it in a sloppy excision it depends on which side the sloppy excision is on It depends on random chance in generalized but in specialized it is the same gene or genes in every particle, if you could grow the phages in specialized transduction (called transducing phages – the diagram second from the bottom in specialized) we could harvest them and infect whatever bacteria we want to have that new allele and then manipulate those cells the way we want to It seems like you couldn’t grow transducing phages though, but there couldn’t be another cycle of infection because the phage is missing some of its viral genes, only some of them are there, it doesn’t seem like you could grow them but you can manipulate them to make it possible in the lab o What does it need that you could have to provide to that cell so that that DNA could undergo another cycle of reproduction (the last cell in the specialized column) you could have to provide it with the rest of the genes, which are in a particle called a helper phage which will have to come and do a “co-infection” with the transducing phage you want to grow more of and the helper phage that has the extra genes that lets it go through another lytic cycle to produce tons and tons of the transducing phages o This is a good way of introducing DNA into cells that you want because virus’ are very good at infection o Know difference between generalized and specialized transduction How is one dependent on lytic vs. lysogenic What are steps of those cycles that bring about generalized vs. specialized What can you get from each? Three ways to transfer DNA o Transformation o Conjugation o Transduction In both cases it is the phage particle that carries the DNA from the donor to the recipient, and the recipient is a recombinant (still has the same alleles it always had and has new alleles at other genes) it has a new combination of alleles that may never have existed before Complementation analysis o Goal of this process is to learn the mutant genotype that is causing a mutant phenotype in this particular case o In this case the strain we are working with is Bio - which means biotin (a type of vitamin) it is a vitamin cells generally need, but wild type bacteria can make their own biotin, this one can’t so it is an auxotroph (cannot make the vitamin that it needs) o There are five Bio genes that encode subunits of enzymes or enzymes that catalyze the steps of the pathway to make biotin o The names of those genes are bioA so the Bio- strain could be bioA- bioB bioC bioD bioF any one of these genes could be minus to make the Bio- o we will figure out what it takes to fix the problem and then that will tell us what the problem was in the
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

3.1.07 - 3.1.2007 Generalize vs specialized refer to what...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online