Mechanistic insights into staphylopine-mediated metal acquisition

Abstract

Metal acquisition is vital to pathogens for successful infection within hosts. Staphylopine (StP), a broad-spectrum metallophore biosynthesized by the major human pathogen, , plays a central role in transition-metal acquisition and bacterial virulence. The StP-like biosynthesis loci are present in various pathogens, and the proteins responsible for StP/metal transportation have been determined. However, the molecular mechanisms of how StP/metal complexes are recognized and transported remain unknown. We report multiple structures of the extracytoplasmic solute-binding protein CntA from the StP/metal transportation system in apo form and in complex with StP and three different metals. We elucidated a sophisticated metal-bound StP recognition mechanism and determined that StP/metal binding triggers a notable interdomain conformational change in CntA. Furthermore, CRISPR/Cas9-mediated single-base substitution mutations and biochemical analysis highlight the importance of StP/metal recognition for StP/metal acquisition. These discoveries provide critical insights into the study of novel metal-acquisition mechanisms in microbes.

Programmable adenine deamination in bacteria using a Cas9–adenine-deaminase fusion

“…The samples for ICP-OES were prepared following the protocols described in literatures. 41,42 S. aureus RN4220 strains were cultured at 30 C in 20 mL of CDM (supplemented with 0.5 mM CoCl 2 ). When the cells grew to exponential phase (OD 600 $ 0.6-0.8), the cultures were chilled on ice for 10 min and then harvested by centrifugation at 7000 g at 4 C for 10 min.…”

Synthetic biology approaches towards the recycling of metals from the environment

“…Another set of metal-transporters, the ABC permeases found in Gram-positive bacteria, have been shown to promote the uptake of metal ions from the surrounding media such as soil, water, or from host cells, and in Staphylococcus sp. this includes, copper, cobalt, zinc, and nickel [ 67 ]. This ability can be directly applied across the whole format of biorecovery of metals ( Figure 1 ).…”

N-Alkyl-α-amino acids in Nature and their biocatalytic preparation

“…However, L,L-(S,S)-opines, such as L,L-(S,S)-succinamoprine, have also been identified (Chilton et al, 1985). A more complex example is that of a new class of bacterial opine metallophores, such as staphylopine (9) produced by Staphylococcus aureus, that play a key role in pathogenesis by sequestering metals from their host (Song et al, 2018). These are biosynthesised from three amino acids by the action of R-selective 3-amino-3-carboxypropyltransferase (nicotianamine synthase) catalysed Nalkylation followed by S-selective coupling of the resultant product to a further α-ketoacid by an opine dehydrogenase (McFarlane et al, 2018;McFarlane and Lamb, 2017).…”