APPENDIX E 
Table 2. Guidelines for experiments with E. col i 
host-vector systems using DNA derived from 
prokaryotes. "Shotgun" experiments 
Conta i nment 
Fore ign 
DNA source Physical Biological 
Prokaryotes : 
"Exchangers" 
a/ 
Cl ass 
1 (CDC) 
PI 
EK1 
b/ 
C 1 ass 
2 (CDC) 
P2 
EK1 -EK2 
b/ 
P 1 ant 
pathogens 
P2 
EK1 -EK2 
Non-exchangers" 
Class 1 (CDC) 
P2 
or 
EK2 
P3 
EK1 
Class 2 (CDC) 
P3 
EK2 
Plant pathogen 
P3 
EK2 
a/ 
CDC refers to the classification of Etiologic Agents on the Basis of 
Hazard, as Published by the Center for Disease Control (CDC), United 
States Public Health Service, 
b/ 
EK1 or EK2, depending on whether the species is of I ow or moderate 
pathogen icity. 
Appendix E — 28 
