Ricerc@Sapienza

Acid resistance (AR) in Escherichia coli is an important trait that protects this microorganism from the deleterious effect of low-pH environments. Reports on biofilm formation in E. coli K12 showed that the genes participating in AR were differentially expressed. Herein, we investigated the relationship between AR genes, in particular those coding for specific transcriptional regulators, and their biofilm-forming ability at the phenotypic level.

Many neutralophilic bacteria have developed several strategies to overcome the life-threatening effect of the exposure to a mild-to-harsh acid stress [1]. Among these strategies, the amino acid-dependent systems were shown to be quite widespread amongst gram-positive and –negative bacteria, and their activities overlap so to cover a rather large pH range, from 6 to

Experimental studies showed that gut-derived lipopolysaccharide (LPS) is pro-atherogenic, however, its relationship with human atherosclerosis is still to be defined. We investigate if gut-derived LPS from Escherichia Coli localizes in human carotid plaque and its potential role as pro-inflammatory molecule in the atherosclerotic lesion. LPS from Escherichia Coli and Toll-like receptor 4 (TLR4) were studied in specimens from carotid and thyroid arteries of 10 patients undergoing endarterectomy and 15 controls matched for demographic and clinical characteristics.

Satureja montana essential oil (SEO) presents a wide range of biological activities due to its high content of active phytochemicals. In order to improve the essential oil’s (EO) properties, oil in water nanoemulsions (NEs) composed of SEO and Tween-80 were prepared, characterized, and their antimicrobial and antibiofilm properties assayed against Escherichia coli strains isolated from healthy chicken.

Poloxamers are nontoxic, amphiphilic copolymers used in different formulations. Due to its surfactant properties, Poloxamer 338 (P388) is herein proposed as a strategy to avoid biofilm formation often causing recalcitrant catheter-associated urinary tract infections (CAUTI). The aim is to evaluate the ability of P388 coatings to affect the adhesion of Ec5FSL and Ec9FSL Escherichia coli strains on silicone urinary catheters.

The structural characterization of the lipopolysaccharide (LPS) from extremophiles has
important implications in several biomedical and therapeutic applications. The polyextremophile
Gram-negative bacterium Halobacteroides lacunaris TB21, isolated from one of the most extreme
habitats on our planet, the deep-sea hypersaline anoxic basin Thetis, represents a fascinating
microorganism to investigate in terms of its LPS component. Here we report the elucidation of

Escherichia coli glutamate decarboxylase (EcGadB), a pyridoxal 5’-phosphate (PLP)-dependent enzyme, is highly specific for L-glutamate and was demonstrated to be effectively immobilised for the production of γ-aminobutyric acid (GABA), its decarboxylation product. Herein we show that EcGadB quantitatively decarboxylates the L-isomer of D,L-2-amino-4-(hydroxyphosphinyl)butyric acid (D,L-Glu-γ-PH), a phosphinic analogue of glutamate containing C-P-H bonds.

Background and aim: Plasmid-mediated colistin resistance mechanisms have been identified worldwide in the past years. A multiplex polymerase chain reaction (PCR) protocol for detection of all currently known transferable colistin resistance genes (mcr-1 to mcr-5, and variants) in Enterobacteriaceae was developed for surveillance or research purposes. Methods: We designed four new primer pairs to amplify mcr-1, mcr-2, mcr-3 and mcr-4 gene products and used the originally described primers for mcr-5 to obtain a stepwise separation of ca 200 bp between ampli-cons.

The emergence of carbapenemase-producing Enterobacteriaceae (CPE) is a critical concern worldwide. In Italy, CPE isolates are very frequent, with the KPC enzyme types strongly predominant whereas the New Delhi metallo-?-lactamase (NDM) enzymes are extremely rare. Here we report the first detection of NDM-5-producing Escherichia coli sequence type 167 (ST167) isolates from two patients with urinary tract infection (Ec001 and Ec002 from urines), including one with colonisation (Ec003 from faeces) admitted to the same hospital 2 months apart in 2017.

Objectives In this study we compared the recently described mcr-4-positive Salmonella enterica monophasic variant, isolated in 2016 in two Italian patients affected by gastroenteritis, with the first mcr-4-positive Salmonella isolate identified in 2013 in a pig at slaughter in Italy. Methods WGS of the two Salmonella isolates of human origin was performed using a MiSeq instrument (Illumina).