Candida krusei

[Terrence Lyttle]

    I recently posted a message to the Drosophila group concerning the 
use of Candida as a food source sprayed on culture media which also helps 
eliminate bacterial contaminations.  I inadvertently perpetuated a 
misspelling of the species name that is a carryover from my undergraduate 
days (and has apparently become fixed in my somewhat fossilized brain).  
The species name is Candida krusei (not crusiae, as in my previous 
post).  I noted that strains of this species are available from the 
American Type Culture (at a cost, of course), and that it should be 
benign in humans.  When we obtained our culture from ATCG, they only had 
isolates derived from plant material.  It has been brought to my 
attention that now there are a number of isolates from human sources, 
which is somewhat worrisome.  As far as I understand, krusei is not a 
problem for humans (unlike C. albicans), and we have never had any 
problem with these yeast cultures over the 15 years or so that they have 
been present (off and on) in our laboratory.  If anyone is interested 
obtaining strains from ATCG, we are using strain #22985 (it also goes 
under the name C. requinyii -- I don't know why).  If people are really 
worried about a potential problem for humans, perhaps it would be better 
to try strain #60585, which came from a rye sourdough starter in 
Germany. That should be innocuous enough, one hopes!  As a purely 
nonscientific piece of information -- note that healthy Candida krusei 
cultures should smell a bit like juicy fruit gum.
   Terry Lyttle