Coreceptor use. The sequence reads were aligned with the BaL consen-Scientific RepoRts | 7:42215 | DOI: 10.1038/srepwww.nature.com/scientificreports/number of negatively charged amino acids (D and E) from the number of positively charged ones (K and R). The CM classifier (generic prediction) was used to predict tropism with cleaned data of V3 amino acid sequences20.Determining the position-specifi