Characterization of a Mycobacterium tuberculosis Nanocompartment and Its Potential Cargo Proteins

Abstract

Background: Mycobacterium tuberculosis has a probable nanocompartment (Mt-Enc). Results: Mt-Enc self-assembles into a 60-subunit cage that encapsulates enzymes via their C-terminal tails, which remain active within Mt-Enc. Conclusion: Cargo proteins are potentially involved in host oxidative stress response, suggesting that enzyme encapulation may be a mechanism to evade host immune assault. Significance: Mt-Enc may be utilized as a novel therapeutic delivery mechanism.

A structural and functional perspective of DyP-type peroxidase family

“…Notably, two reports have classified AnaPX duce protoporphyrin IX from heme in vitro were not shown [27]. 186 Moreover, Mt-DyP also does not show this activity [24]. Therefore, Tat-dependent export into 197 the periplasmic space has been confirmed [28][29][30][31].…”

Prokaryotic nanocompartments form synthetic organelles in a eukaryote

“…In vivo protein encapsulation is guided by short targeting peptides (TPs), which are located at the C-termini of cargo proteins. A large variety of native cargo proteins has been identified in bacteria and archaea, including peroxidases and ferritin-like proteins involved in stress response pathways 11,[14][15][16] . Using Escherichia coli as a host, it has been shown that packaging of non-native proteins into the encapsulins from Thermotoga maritima and Brevibacterium linens can be achieved by fusion of targeting peptides to the intended cargo 17,18 .…”

The multihued palette of dye-decolorizing peroxidases

“…Intriguingly, dypB is operonically coupled with enc in a number of organisms, such as Thermotoga maritima as well as the actinobacteria R. jostii RHA1 and M. tuberculosis (Fig. 4B) [30][31][32]. The enc gene encodes a 29 kDa protein that assembles to form encapsulin, a bacterial nano-compartment of $1.8 MDa [32].…”