She wrote her doctoral thesis on the medical uses of nonpathogenic organisms. Damaged skin can cause nonpathogenic bacteria to become pathogenic. This portion of the plasmid is highly conserved and found in nonpathogenic "Rhodococci" plasmids. This has been demonstrated to be effective with the nonpathogenic anaerobe "Clostridium sporogenes". Nonpathogenic strains are also present in water ecologies. The filovirus was found to be distinct from EBOV and to be nonpathogenic for humans. A particular strain of bacteria can be nonpathogenic in one species but pathogenic in another. They also transmit "Trypanosoma melophagium" nonpathogenic protozoan parasite of sheep. These pigments were synthesized by nonpathogenic strains of "E. nigrum". LAMS capped with phosphoinositol are typically found in nonpathogenic species including M. smegmatis. Streptococcus equinus is a Gram-positive, nonhemolytic, nonpathogenic, lactic acid bacterium of the genus "Streptococcus". This single cell eukaryote is nonpathogenic and easily grown and manipulated in the lab. It was first named "Monilia parapilosis" and considered nonpathogenic. The main microorganisms used are nonpathogenic actinomycetes, Nocardia and Streptomycetes. PVS-RIPO consists of a genetically modified nonpathogenic version of the oral poliovirus Sabin type 1.