M13tv phage problem (In n)

[Norio Suzuki]

Dear Readers,

 My friend is in a trouble about M13tv phage.
She is trying to make a site-directed mutation by using 
"gapped duplex method".

 At the first step, she cloned  one fragment,which is human 
anti-something,into M13tv phage. M13tv phage has Amber 
mutations and rest is same as M13mp phage. she put it into 
E.coli JM109 following standard transformation protocol. But
she got only unclear and small plaques. Off course, there 
was no problem in a control(M13mp page) plate. 

 I think the cause is on JM109 but JM109 has exactly supE 
mutation to rescue Amber mutation. Should she use another 
supE strain BMH71-18 mutS ?

Thank you.

Norio Suzuki
Dep. of Molecular Life Science
Tokai University School of Medicine
mail to norio at cc.u-tokai.ac.jp