Single-stranded DNA prep reference?

[Masami Yoshimura]

On Thu, 15 Jun 1995, Josh Goldstein wrote:

>    Jupin and Gronenborn, 1995.  Abundant, easy and reproducible production
> of ssDNA from phagemids using helper phage-infected competent cells. 
> Nucleic Acids Research, 23:3, pp.535-536
> 
>    You know, I tried this myself and it didn't work. They used the
> hexamminecobalt chloride method of preparing competent cells, while I used
> CaCl, so maybe that was the problem.  Let me know if it works for you.
> 
> Josh Goldstein
> josh at panda.uchc.edu
> 
> 
I read this paper and thought that it was a neat idea.  However, the 
photo they showed in Fig. 1 made me wonder.  In my hand and references I 
know, circular ssDNA migrates faster than corresponding super-coiled 
dsDNA.  The bands in the Fig look too big.  Are they something else?  
Please correct me, if I am wrong.  Masami.