dam methylated DNA in dam - straights - (Feb/05/2010 )

I have a vector that is in a glycerol stock of a dam+ strain. This methylates my XbaI site. If I transform this purified plasmid from a dam+ strain into a dam- strain will the methylation be removed?

Yes -- as the plasmid is replicated in the dam- strain, the newly-synthesized DNA will not be dam methylated (that's not to say the DNA will be entirely unmethylated, just that dam methylation will be absent).