Serratia Marcescens Strain 933

[Karl Roberts]

Dear Brian,
	It sounds to me like you don't have the strain you ordered.  S. 
marscens generally is a good species for demonstrating 
environmentally-induced phenotypic expression (red-25 to 30 degrees, 
white-37 degrees).  If your m.o. is exhibiting pigmentation, you need to
contact your supplier and have a new culture sent.  
Joe
On Thu, 20 Mar 1997, Poolside wrote:

> Hi,
>      My advanced biology class is currently working with S. Marcescens
> strains 933, D-1, and WCF. We are using these bacteria to study gene
> trasnference. Strain 933 is an unpigmented mutant. Our problem has
> been that strain 933 has been cultured on nutrient agar, and in about
> 90% of our cultures has produced a red pigiment. If anyone has any
> ideas for a solution to this problem please reply to me by e-mail as I
> do not subscribe to this group. Thanks
> 
> Brian Donovan
> Minnechuag Regional High School
>