Construction and Characterization of a Mutant Library for the P Constitutive Promoter in Lactic Acid Bacteria.

Promoters are crucial elements for controlling gene expression in cells, yet lactic acid bacteria (LAB) often lack a diverse set of available constitutive promoters with quantitative characterization. To enrich the LAB promoter library, this study focused on the known strong constitutive promoter P in LAB. Through error-prone PCR and dNTP analog-induced random mutagenesis, a library of 247 mutants of P was generated by using the red fluorescent protein (RFP) fluorescence intensity as a high-throughput screening indicator in Streptococcus thermophilus.

Chronic restraint stress affects the diurnal rhythms of gut microbial composition and metabolism in a mouse model of depression.

Background: Depression is a common mental disorder accompanied by gut microbiota dysbiosis, which disturbs the metabolism of the host. While diurnal oscillation of the intestinal microbiota is involved in regulating host metabolism, the characteristics of the intestinal microbial circadian rhythm in depression remain unknown. Our aim was to investigate the microbial circadian oscillation signature and related metabolic pathways in a mouse model with depression-like behaviours.

High glucose induces pro-inflammatory polarization of macrophages by inhibiting immune-responsive gene 1 expression.

Objectives: To investigate the effect of high glucose on macrophage polarization and the role of immune-responsive gene 1 (IRG1) in mediating its effect.

Methods: RAW264.7 cells were transfected with IRG1-overexpressing plasmid or IRG1 siRNA via electroporation and cultured in either normal or high glucose for 72 h to observe the changes in cell viability and morphology using CCK-8 assay and phase contrast microscopy.

Regulating d-p band center with selenium vacancy in iron diselenide nanoarrays towards sulfion-assisted seawater electrolysis for chlorine-free hydrogen production.

Defect engineering is considered one of the most powerful strategies for regulating the catalytic activity of electrocatalysts. A deep understanding of the defect-involved mechanism in electrocatalytic process is of great importance but remains a challenging task. In this study, an anionic Se-vacancy (V) was introduced into iron diselenide (FeSe) nanoarrays, enabling the catalyst to exhibit improved electrocatalytic performance for sulfion oxidation reaction (SOR).