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.

Several imaging methodologies have been used in biofilm studies, contributing to deep- ening the knowledge on their structure.

Malassezia species are natural inhabitants of the healthy skin. However, under certain
conditions, they may cause or exacerbate several skin diseases. The ability of this fungus
to colonize or infect is determined by complex interactions between the fungal cell and
its virulence factors. This study aims to evaluate “in vitro” the hydrophobicity levels,
the adherence on a plastic surface and the biofilm formation of 16 clinical isolates of
Malassezia furfur. Cellular surface hydrophobicity (CSH) levels were determined by twophase

L’olio essenziale di Origanum vulgare e due principi attivi che lo caratterizzano, il carvacrolo e il timolo, possiedono proprietà antimicotiche e antibiofilm in particolare nei confronti dei funghi appartenenti al genere Candida. Queste interessanti attività potrebbero essere utilizzate come coadiuvante e/o in alternativa alle convezionali terapie farmacologiche.

The aim of the work is to assess the antimicrobial activities of Cell Free Supernatants (CFS) and Membrane Vesicles (MVs), produced by Lactobacillus reuteri DSM 17938, versus Gram-positive and Gram-negative bacteria and investigate their metabolic profiles. The Minimum Inhibitory Concentration was determined through the broth microdilution method and cell proliferation assay and the Minimum Bactericidal Concentration was determined by Colony Forming Units counts.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a prominent cause of nosocomial infections associated with high rates of morbidity and mortality, particularly in oncological patients. The hypermucoviscous (HMV) phenotype and biofilm production are key factors for CRKP colonization and persistence in the host. This study aims at exploring the impact of CRKP virulence factors on morbidity and mortality in oncological patients. A total of 86 CRKP were collected between January 2015 and December 2019.

The study aimed to evaluate the antimicrobial effect of photodynamic therapy (PDT) with the use of Toluidine Blue (TB) on extracted teeth infected with biofilms of Enterococcus faecalis. Fifty-four extracted teeth with single-roots and single canals were mechanically shaped, autoclaved, and contaminated with E. faecalis.

Early childhood caries (ECC) is a severe manifestation of carious pathology with rapid
and disruptive progression. The ECC microbiota includes a wide variety of bacterial species, among
which is an anaerobic newly named species, Scardovia wiggsiae, a previously unidentified
Bifidobacterium. Our aim was to provide the first ultrastructural characterization of S. wiggsiae and
its biofilm by scanning electron microscopy (SEM) using a protocol that faithfully preserved the