Plasmids for the production of 100bp and 1kb DNA ladders

ChenHA hzhen at
Fri Aug 25 11:03:21 EST 2006

On Fri, 25 Aug 2006 14:55:38 GMT, dk at (DK)

>In article <9i2ue21p56l7sebkk6hpvjroogkm1tlccl at>, ChenHA <hzhen at> wrote:
>>On Fri, 25 Aug 2006 14:49:51 +0200, ""
>><seggewis at> wrote:
>>>I search for suitable plasmids for the production of 100bp and 1 kb DNA 
>>>ladders, respectively.
>>I don't have the plasmid here, but you can make them yourself if you
>>want to.   The reference for this is 
>>Anonymous (1989) BRL Focus 11,36
>>Unfortunately I don't have the paper as well, and it is no longer
>>available on the web, when Gibco-BRL disappeared into Invitrogen.  So
>>my question  is - has anyone a copy of this or know where I can find
>Yes, every one of Focus issues is still available for download in PDF:

Thanks.  Looks like that reference is just a description of the 1kb
ladder, no the construction itself.  I'm sure I have read a paper that
describes how the ladder is constructed, do you know which one that
might be?    I can't be certain about this, but I think a fragment of
DNA has two different restriction sites, one of which when ligated
destroys the restriction site, but the other still can be cut, so when
the process is repeated and you turn the fragment into concatemers
within the plasmid, you can get  multiples of 1000 bp when when cut
with one enzyme.  

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