GROWTH in minimal MEDIA (M9)

[F. Ferreira]

Hi, I have been growing an E.coli strain (SG935-protease deficient) in 
minimal media (M9) in a 1 liter shake flask for more than 150 hours.  The 
bacteria reached stationary phase after approx. 15 hours (growth at 32 C).  
however, surprisingly, they seem to have remained in stationary for several 
days now.  Furthermore, SDS-PAGE analysis of a protein which we expect to 
be overproduced in this type of media is still observed after at least 75 
hours with no significant dergradation.  Does this growth profile seem 
nortmal? Please post any comments or E-mail me at slxb at hotmail.com if 
anyone has observed a similar behaviour before...  Thanks in adv. Francisco