beneficial virus question

[Mamink at aol.com]

       In the back of my memory is a questionable recollection of a paper
published in the late '70s early '80s concerning growth of bacteriophage
lambda lysogens in chemostat cultures.  I was interested in examples of a
similar "beneficial virus"  at the time.  As I recall the lysogen had a lower
"delta"G than an uninfected culture, when adjusting for certain growth
parameters. 
       Even if my memory is right, one cannot generalize the statement to
animal or plant viruses, or even other phage.  But it may serve as an example
to you.  Maybe other phage investigators could comment.
       Sorry I can't be more specific, it was many beers ago.