10/7/77 
To: Dr. Donald Fredrickson 
Director, National Institutes of Health, Bethesda, MD 
As active workets in Bacillus microbiology , we strongly support the 
requests of a number of investigators to use Bacillus subtilis for DNA 
recombinant studies. The development of eloning technology with this 
species will be of great value for genetic investigations of a number, 
of processes that cannot be studied in Escherichia coli : Specifically, 
this organism undergoes a simple developmental cycle and a genetic 
study of the process will allow conclusions applicable to higher 
forms of differentiation. A.t this time the genetics of this organism 
is hampered by the lack of a suitable system for complementation and 
dominance analysis. The construction of extra chromosomal- elements 
is possible with DNA recombinant technology using natural plasmids 
for this species., 
B_. subtilis Is a soil organism lacking known toxins for man, 
animals^ and plants. A related strain, 3J. natto, is consumed in large 
quantities as a component of soybean cakes without causing infections. 
Nevertheless, there are reports of human infection involving B. subtills. 
We do not believe that these rare incidents indicate that B.. subtilis 
is pathogenic. Compromised hosts can be invaded by any microorganism 
and B. subtilis is no exception. subtilis is highly aerobic and 
very sensitive to several components of normal human serum. It Is an 
unlikely candidate for human Infections. Furthermore, It Is highly 
sensitive to most commonly used antibiotics and can therefore be readily 
controlled. 
The ability to form spores is characteristic and as such would 
[Appendix A — 24] 
