Poster Presentation International Peptide Symposium 2023

Synthesis of covalent peptide inhibitors for CHIKV nsP2pro (#249)

Junming He 1 , Jennifer Ton 1 , Colin Jackson 1 , Christoph Nitsche 1
  1. Australian National University, Acton, ACT, Australia

The Chikungunya virus (CHIKV) is an alphavirus transmitted to humans by the Aedes mosquitoes surrounding the tropical and subtropical regions of the world. The virus has been documented in Africa since 1952 and has since set-off sporadic outbreaks surrounding the Indian Ocean from 2007. The CHIKV disease is characterized by an abrupt onset of fever, headaches, and fatigue, accompanied by chronic musculoskeletal pain and severe joint pain. To date there is limited data on the specific inhibition of CHIKV activity. Our research aims to target the non-structural protein-2 protease (nsP2pro), which is a cysteine protease, mediated by a cysteine-histidine dyad1. Preliminary data on the inhibition of CHIKV nsP2pro have proven to be challenging. Through literature investigation and in silico modelling we have designed covalent peptide inhibitors and aim to synthesize short peptides incorporating reactive functional groups (warheads), such as aldehyde, α‑ketoamide, epoxide, and nitrile substituents, which are predicted to irreversibly bind at the active site. This research will highlight the efforts towards synthesizing irreversible peptide inhibitors. The need to develop a vaccine and antiviral therapeutic for CHIKV is much anticipated. The nsP2pro enzyme is also highly conserved among alphaviruses, providing opportunities for broad-spectrum inhibitors that may be active against Ross River and other alphaviruses. The ongoing epidemic from 2019 should bring awareness to the dangers of unchecked viruses in third-world countries that can quickly spread to first-world countries.

  1. 1. Narwal, M.; Singh, H.; Pratap, S.; Malik, A.; Kuhn, R. J.; Kumar, P.; Tomar, S., Crystal structure of chikungunya virus nsP2 cysteine protease reveals a putative flexible loop blocking its active site. Int. J. Biol. Macromol. 2018, 116, 451-462.