5 replies to this topic

[Rajdeep Basu]

Is it possible to express bacteriophage in mammalian cells by codon optimization? Any relevant literature? thanks in advance.

[mdfenko]

Are you trying to infect mammalian cells with bacteriophage?

 

if so, then i wouldn’t expect the bacteriophage to be able to attach to the mammalian cells

[Rajdeep Basu]

Absolutely, thanks! How about expressing phage from a codon optimized plasmid?

Edited by Rajdeep Basu, 06 August 2020 - 08:46 AM.

[mdfenko]

Would the plasmid contain the entire viral genome?

 

you may be able to produce individual proteins with a plasmid but i doubt that you would be able to produce all of the proteins, replicate the DNA and assemble the phage.

[Rajdeep Basu]

That makes sense! Thanks so much.

[bob1]

In addition to mdfenko's answer - it is common to express mammalian viruses from plasmids, often multiple plasmids to make up the genome.  Bacteriophage can, with some modifications for host-cell receptors, insert into a mammalian cell and express genes from mammalian derived cassettes (e.g. here (PDF)).

 

However, in the initial question you asked:

 

 

Is it possible to express bacteriophage in mammalian cells by codon optimization? Any relevant literature? thanks in advance.

The short answer is: no, because the bacteriophage has a bacterial expression system that is not utilized by mammalian cells. If (as in the linked paper) you can insert a mammalian promoter, then you should be able to express some or all of the proteins needed, but this does not necessarily equate to assembly as you need the right components in the right locations at the right time for bacteriophage assembly. In bacteria which only really have one cellular compartment this isn't a problem because all the components are in proximity to each-other, but mammalian cells have many compartments (e.g. golgi, nucleus, endoplasmic reticuluum, etc.). Each of these compartments have assigned roles such as protein generation (ER), DNA replication (nucleus), which would separate the functions of each out so that while capsid might be produced, there wouldn't be any DNA to go into it or vice-versa.

 

I think you are also misunderstanding what codon-optimization is. It is a system to make the expression of genes more amenable to protein production in mammalian cells by altering the DNA so that forms of the codons used are the ones more commonly used in mammalian cells. Just because you codon optimize something doesn't mean it will express in a mammalian cell, you also need mammalian promoters and terminators, as well as a means of getting the DNA into the cell in the right orientation respective to the promoter. There are other components that can help too such as the Kozac sequence.