S-layer proteins as a source of carotenoids: Isolation of the carotenoid cofactor deinoxanthin from its S-layer protein DR_2577

The Role of Iron and Copper on the Oligomerization Dynamics of DR_2577, the Main S-Layer Protein of Deinococcus radiodurans

“…Specifically, the S-layer of D. radiodurans has been studied for its interesting functional traits provided by the presence of the carotenoid deinoxanthin associated to its main protein DR_2577 (Farci et al, 2016a, 2017). This S-layer protein, through its cofactor, allows the S-layer to behave as a shield against UV stress and desiccation (Farci et al, 2016a).…”

“…This bacterium has been extensively studied for its surface layer (S-layer), a cell structure characterized by a main protein complex named S-layer Deinoxanthin Binding Complex (SDBC). SDBC is a homo-hexamer of ~760 kDa and is composed of the S-layer protein DR_2577, also known as SlpA, to which is bound the carotenoid cofactor deinoxanthin (Farci et al, 2015, 2016a, 2017). We recently showed that this protein complex exhibits spectral properties and thermal stability that comply with the resistance to UV-radiation and deep desiccation (Farci et al, 2016a, 2018a).…”

Structural analysis of the architecture and in situ localization of the main S-layer complex in Deinococcus radiodurans

“…The S-layer is often present in Bacteria and Archaea, carrying resistance to extreme conditions (Gentner and Mitchel, 1975;Sleytr and Sà ra, 1997;Pavkov-Keller et al, 2011;Farci et al, 2016Farci et al, , 2018Kumar et al, 2021), and plays essential roles in providing primary cell properties such as rigidity, adhesion, and shape (Sleytr et al, 1993;Beveridge et al, 1997;Rachel et al, 1997;Fagan and Fairweather, 2014). Despite their potentials in areas that span from biomedicine to nanotechnology (Hall et al, 2001;Mark et al, 2006;Farci et al, 2017), insights into the molecular arrangements occurring between the S-layer and the underlying cell wall are still limited. With the exception of previous pioneering studies (Baranova et al, 2012;Bharat et al, 2017), an extended structural characterization of these proteins and their S-layers at subnanometer resolution has been extremely difficult, especially due to their self-assembly properties and related tendency to aggregate (Pum et al, 2013).…”

Gold Nanoparticles Biosynthesized and Functionalized Using a Hydroxylated Tetraterpenoid Trigger Gene Expression Changes and Apoptosis in Cancer Cells

“…Bacterial metabolites have gained attention in AuNP synthesis because bacteria can be cultured economically and their metabolites can be prepared without seasonal and geographic effects. , DX was identified as a strong antioxidant in D. radiodurans for defense against ionizing radiation and oxidants. , DX, which contains multiple hydroxyl groups, is more polar and reactive than carotenes (β-carotene and lycopene) and xanthophylls (lutein and zeaxanthin). − Recent studies demonstrated that DX was a potent chemopreventive agent and applicable in dietary supplementation. , …”