Genomic divergence of an HIV-2 from a German AIDS patient probably infected in Mali.
 The complete nucleotide sequence of an HIV-2 isolate derived from a German AIDS patient with predominantly neurological symptoms is reported.
 The HIV-2BEN sequence is highly divergent from those of previously described HIV-2 and SIV strains.
 Evolutionary tree analysis of eight HIV-2 sequences reveals the existence of three HIV-2 groups.
 HIV-2BEN belongs to a group with two isolates from Ghana and The Gambia.
 Based on a comparison of HIV-2BEN with six HIV-2 isolates, SIVsmm and SIVmac, the variability of the structural env and gag proteins is similar within the HIV-2/SIVsmm/mac and HIV-1 groups.
 In contrast, the regulatory HIV-1 proteins are more highly conserved than those from HIV-2 strains.
 Multiple sequence alignments reveal that some domains of the envelope and regulatory proteins are well conserved among HIV-1, HIV-2/SIVsmm/mac, SIVagm and SIVmnd.
 The identification of conserved domains within the external glycoprotein could help to develop broadly active vaccines.
