Influence of CNTRENE^®C100LM carbon nanotube material on the growth and regulation ofEscherichia coli

Abstract

The growing use of carbon nanotubes (CNTs) in industrial and consumer products raises important questions about their environmental fate and impact on prokaryotes. In the environment, CNTs are exposed to a variety of conditions (e.g., UV light) that could lead to decomposition and changes in their chemical properties. Therefore, the potential cytotoxic effect of both pristine and artificially aged carboxyl functionalized CNTRENE® C100LM CNTmaterial at neutral and acidic conditions on Escherichia coli K12 was analyzed using a minimal inhibitory concentration (MIC) assay, which also allowed monitoring of non-lethal growth effects. However, there were no observable MIC or significant changes in growth behavior in E. coli K12 when exposed to pristine or aged CNTs. Exposure to pristine CNTRENE® C100LM CNT material did not appear to influence cell morphology or damage the cells when examined by electron microscopy. In addition, RNA sequencing revealed no observable regulatory changes in typical stress response pathways. This is surprising considering that previous studies have claimed high cytotoxicity of CNTs, including carboxyl functionalized single-walled CNTs, and suggest that other factors such as trace heavy metals or other impurities are likely responsible for many of the previously reported cytotoxicity in E. coli and possibly other microorganisms.

Influence of ultrasonication on the dispersion and enhancing effect of graphene oxide–carbon nanotube hybrid nanoreinforcement in cementitious composite

“…The peak shift is likely due to the damage or defects introduced by the ultrasonication. Compared to the reported peak shift for heavily damaged GO or CNTs, which is from 250 to 270 nm [43], the results here indicate that time-or powder-controlled ultrasonication induces minimal damage in the surface of the CNTs or GO. Based on the reported relationship between defects and mechanical properties of CNTs and GO, it is reckoned that such a level of damage is unlikely to cause a significant decrease in the mechanical properties of the GO [24] or CNTs [44,45].…”

Metagenomic insights into the response of soil microbial communities to pathogenic Ralstonia solanacearum

“…beta-lactamases (Ralstonia-Bradyrhizobium/Pseudomonas). Moreover, we have observed the sharing of the transcriptional anti-activator TraM, which directly regulates quorum sensing in plant pathogens, between Ralstonia and Xanthomonas (Alakavuklar et al, 2021); Additionally, transcription regulator AlpA and AcrR that respond to environmental stressors, such as heavy metals (Twibell et al, 2017), is shared between Ralstonia and Klebsiella. These proteins serve as further examples of HGT events associated with a comprehensive response to abiotic stress resistance (Supplementary Table S3; Figure 9F).…”

Ultrafiltration of α-Lactalbumin Protein: Acquaintance of the Filtration Performance by Membrane Structure and Surface Alteration

“…single-and multi-walled dimensions show similar IR spectra. sented by the peaks around 3200-3400 cm −1 , while the C-H stretc C = C stretching, C-O-H, and the C-C-C bending are indicated by 1385, and 1090 cm −1 , respectively [30].…”

“…O-H groups are represented by the peaks around 3200-3400 cm −1 , while the C-H stretch appears at ∼2920 cm −1 . C = C stretching, C-O-H, and the C-C-C bending are indicated by the peaks around 1653, 1385, and 1090 cm −1 , respectively [30].…”