Diagnostic accuracy of fresh drooled saliva for SARS-CoV-2 in travelers.

Background: The standard for SARS-CoV-2 diagnosis is RT-PCR from nasopharyngeal or oropharyngeal swabs. Major airports require COVID-19 screening, and saliva has the potential as a substitute specimen for SARS-CoV-2 diagnosis. We investigated the utility of fresh drooled saliva against NPS for COVID-19 screening of travelers.

Optimized serodiagnosis of Mycoplasma pneumoniae infections.

Serologic methods are well established for the diagnosis of Mycoplasma pneumoniae infections in humans, but they are less sensitive than polymerase chain reaction (PCR). To improve their sensitivity, a new panel of antigens was tested. Compared with PCR results, up to 92% of PCR-positive patients were confirmed by our immunoblotting approach having a specificity between 92.

Identification, expression and serological evaluation of the recombinant ATP synthase beta subunit of Mycoplasma pneumoniae.

Background: Mycoplasma pneumoniae is responsible for acute respiratory tract infections (RTIs) common in children and young adults. As M. pneumoniae is innately resistant to beta-lactams antibiotics usually given as the first-line treatment for RTIs, specific and early diagnosis is important in order to select the right treatment.

The Pta-AckA pathway controlling acetyl phosphate levels and the phosphorylation state of the DegU orphan response regulator both play a role in regulating Listeria monocytogenes motility and chemotaxis.

DegU is considered to be an orphan response regulator in Listeria monocytogenes since the gene encoding the cognate histidine kinase DegS is absent from the genome. We have previously shown that DegU is involved in motility, chemotaxis and biofilm formation and contributes to L. monocytogenes virulence.

The DegU orphan response regulator of Listeria monocytogenes autorepresses its own synthesis and is required for bacterial motility, virulence and biofilm formation.

The Gram-positive intracellular pathogen Listeria monocytogenes is endowed with 17 sets of genes encoding two-component systems. L. monocytogenes is closely related to the Gram-positive model bacterium Bacillus subtilis, in which we have shown previously that the DegS/DegU system plays a central role in controlling stationary phase adaptive responses, including degradative enzyme synthesis and competence.

Contractions and expansions of CAG/CTG trinucleotide repeats occur during ectopic gene conversion in yeast, by a MUS81-independent mechanism.

CAG/CTG trinucleotide repeat tracts expand and contract at a high rate during gene conversion in Saccharomyces cerevisiae. In order to characterize the mechanism responsible for such rearrangements, we built an experimental system based on the use of the rare cutter endonuclease I-SceI, to study the fate of trinucleotide repeat tracts during meiotic or mitotic (allelic or ectopic) gene conversion. After double-strand break (DSB) induced meiotic recombination, (CAG)(98) and (CAG)(255) are rearranged in 5% and 52% of the gene conversions, respectively, with similar proportions of contractions and expansions.