A Cytochrome P450 TxtE Model System with Mechanistic and Theoretical Evidence for a Heme Peroxynitrite Active Species.

The cytochrome P450 homolog, TxtE, efficiently catalyzes the direct and regioselective aromatic nitration of the indolyl moiety of L-tryptophan to 4-nitro-L-tryptophan, using nitric oxide (NO) and dioxygen (O) as co-substrates. Pathways for such direct and selective nitration of heteroaromatic motifs present platforms for engineering new nitration biocatalysts for pharmacologically beneficial targets, among a medley of other pivotal industrial applications. Precise mechanistic details concerning this pathway are only weakly understood, albeit a heme iron(III)-peroxynitrite active species has been postulated.

Multi-Layer Biosensor for Pre-Symptomatic Detection of , the Causal Agent of Yellow Rust.

The yellow rust of wheat (caused by f. sp. ) is a devastating fungal infection that is responsible for significant wheat yield losses.

Metabolic phenotyping of acquired ampicillin resistance using microbial volatiles from Escherichia coli cultures.

Aims: This study sought to assess the volatile organic compound (VOC) profiles of ampicillin-resistant and -susceptible Escherichia coli to evaluate whether VOC analysis may be utilized to identify resistant phenotypes.

Methods And Results: An E. coli BL21 (DE3) strain and its pET16b plasmid transformed ampicillin-resistant counterpart were cultured for 6 h in drug-free, low- and high-concentrations of ampicillin.