Exceptional potency and structural basis of a T1249-derived lipopeptide fusion inhibitor against HIV-1, HIV-2, and simian immunodeficiency virus
Zhu, Y., Zhang, X., Ding, X., Chong, H., Cui, S., He, J., Wang, X., He, Y.(2018) J Biol Chem 293: 5323-5334
- PubMed: 29425101 
- DOI: https://doi.org/10.1074/jbc.RA118.001729
- Primary Citation of Related Structures:  
5YC0 - PubMed Abstract: 
Enfuvirtide (T20) is the only viral fusion inhibitor approved for clinical use, but it has relatively weak anti-HIV activity and easily induces drug resistance. In succession to T20, T1249 has been designed as a 39-mer peptide composed of amino acid sequences derived from HIV-1, HIV-2, and simian immunodeficiency virus (SIV); however, its development has been suspended due to formulation difficulties. We recently developed a T20-based lipopeptide (LP-40) showing greatly improved pharmaceutical properties. Here, we generated a T1249-based lipopeptide, termed LP-46, by replacing its C-terminal tryptophan-rich sequence with fatty acid. As compared with T20, T1249, and LP-40, the truncated LP-46 (31-mer) had dramatically increased activities in inhibiting a large panel of HIV-1 subtypes, with IC 50 values approaching low picomolar concentrations. Also, LP-46 was an exceptionally potent inhibitor against HIV-2, SIV, and T20-resistant variants, and it displayed obvious synergistic effects with LP-40. Furthermore, we showed that LP-46 had increased helical stability and binding affinity with the target site. The crystal structure of LP-46 in complex with a target surrogate revealed its critical binding motifs underlying the mechanism of action. Interestingly, it was found that the introduced pocket-binding domain in LP-46 did not interact with the gp41 pocket as expected; instead, it adopted a mode similar to that of LP-40. Therefore, our studies have provided an exceptionally potent and broad fusion inhibitor for developing new anti-HIV drugs, which can also serve as a tool to exploit the mechanisms of viral fusion and inhibition.
Organizational Affiliation: 
From the MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.