Genome-Scale Investigation of the Regulation of azoR Expression in Escherichia coli Using Computational Analysis and Transposon Mutagenesis.

Bacterial azoreductases are enzymes that catalyze the reduction of ingested or industrial azo dyes. Although azoreductase genes have been well identified and characterized, the regulation of their expression has not been systematically investigated. To determine how different factors affect the expression of azoR, we extracted and analyzed transcriptional data from the Gene Expression Omnibus (GEO) resource, then confirmed computational predictions by quantitative reverse transcription polymerase chain reaction (qRT-PCR).

Biofilm formation by Streptococcus mutans and its inhibition by green tea extracts.

Dental Caries is considered one of the most existing and worldwide common diseases related to the oral cavity affecting both children and adults. Streptococcus mutans is the main cariogenic microorganism involved in the dental caries progression. Natural products such as herbal plants were found to have less side effects and economic value than those of the chemically synthesized antibiofilm agents.

Phenotype-Genotype Characterization and Antibiotic-Resistance Correlations Among Colonizing and Infectious Methicillin-Resistant Recovered from Intensive Care Units.

Introduction: Methicillin-resistant (MRSA) presents a profound hazard to public health. MRSA colonizing skin, mucous membranes, and the anterior nares without clinical symptoms is termed "colonizing MRSA". Upon manifestation of clinical symptoms, it is termed "infectious MRSA".

Azoreductase activity of dye-decolorizing bacteria isolated from the human gut microbiota.

The gut microbiota enriches the human gene pool and contributes to xenobiotic metabolism. Microbial azoreductases modulate the reduction of azo-bonds, activating produgs and azo polymer-coated dosage forms, or degrading food additives. Here, we aimed to screen the healthy human gut microbiota for food colorant-reducing activity and to characterize factors modulating it.

Chemical modification of Aspergillus niger β-glucosidase and its catalytic properties.

Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation). The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein).

'Supermutators' found amongst highly levofloxacin-resistant E. coli isolates: a rapid protocol for the detection of mutation sites.

Fluoroquinolone resistance is gradually acquired through several mechanisms. In particular, chromosomal mutations in the genes encoding topoisomerases II and IV and increased expression of the multidrug efflux pump AcrAB-TolC are the most common mechanisms. In this study, multiplex polymerase chain reaction (PCR) protocols were designed for high-throughput sequencing of the quinolone resistance determining regions of topoisomerases genes (gyrA, parC and parE) and/or the expression regulation systems of multidrug efflux pump AcrAB (acrRAB, marRAB and soxSR).

Emergence of carbapenem-resistant Acinetobacter baumannii harboring the OXA-23 carbapenemase in intensive care units of Egyptian hospitals.

Background: Healthcare-associated infections are a worldwide threat to hospitalized patients, especially those in intensive care units. The prevalence of these infections in Egypt, and their antimicrobial resistance patterns and mechanisms, were investigated in this study.

Methods: A total of 547 cases of healthcare-associated infections were investigated.

Photosynthetic based algal-bacterial combined treatment of mixtures of organic pollutants and CO2 mitigation in a continuous photobioreactor.

An algal-bacterial microcosm was synthetically constructed of Chlorella vulgaris MMl and Pseudomonas MTl. This microcosm was able to treat simulated wastewater supplemented with mixtures of phenol and pyridine up to 4.6 and 4.