Gold Nanoparticles Augment N-Terminal Cleavage and Splicing Reactions in Mycobacterium tuberculosis SufB

• Published in: Frontiers in bioengineering and biotechnology Vol. 9; p. 773303
• Main Authors: Nanda, Ananya, Nasker, Sourya Subhra, Kushwaha, Anoop K, Ojha, Deepak Kumar, Dearden, Albert K, Nayak, Saroj K, Nayak, Sasmita
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 23-12-2021
• Subjects: Bioengineering and Biotechnology; gold nanoparticles; Mycobacterium tuberculosis; NP–intein corona; splicing enhancement; splicing regulation; SufB; splicing enhancement; SufB; Mycobacterium tuberculosis; NP–intein corona; gold nanoparticles; splicing regulation
• ISSN: 2296-4185; 2296-4185
• DOI: 10.3389/fbioe.2021.773303

Protein splicing is a self-catalyzed event where the intervening sequence intein cleaves off, joining the flanking exteins together to generate a functional protein. Attempts have been made to regulate the splicing rate through variations in temperature, pH, and metals. Although metal-regulated protein splicing has been more captivating to researchers, metals were shown to only inhibit splicing reactions that confine their application. This is the first study to show the effect of nanoparticles (NPs) on protein splicing. We found that gold nanoparticles (AuNPs) of various sizes can increase the splicing efficiency by more than 50% and the N-terminal cleavage efficiency by more than 45% in
SufB precursor protein. This study provides an effective strategy for engineering splicing-enhanced intein platforms. UV-vis absorption spectroscopy, isothermal titration calorimetry (ITC), and transmission electron microscopy (TEM) confirmed AuNP interaction with the native protein. Quantum mechanics/molecular mechanics (QM/MM) analysis suggested a significant reduction in the energy barrier at the N-terminal cleavage site in the presence of gold atom, strengthening our experimental evidence on heightened the N-terminal cleavage reaction. The encouraging observation of enhanced N-terminal cleavage and splicing reaction can have potential implementations from developing a rapid drug delivery system to designing a contemporary protein purification system.