A nisin-inducible chromosomal gene expression system based on ICE Tn5253 of Streptococcus pneumoniae, transferable among streptococci and enterococci.

The present work reports the development and validation of a chromosomal expression system in Streptococcus pneumoniae which permits gene expression under the control of Lactococcus lactis lantibiotic nisin. The system is based on the integrative and conjugative element (ICE) Tn5253 of S. pneumoniae capable of site-specific chromosomal integration and conjugal transfer to a variety of bacterial species.

The Mobilome-Enriched Genome of the Competence-Deficient BM6001, the Original Host of Integrative Conjugative Element Tn, Is Phylogenetically Distinct from Historical Pneumococcal Genomes.

is an important human pathogen causing both mild and severe diseases. In this work, we determined the complete genome sequence of the clinical isolate BM6001, which is the original host of the ICE Tn. The BM6001 genome is organized in one circular chromosome of 2,293,748 base pairs (bp) in length, with an average GC content of 39.

Complete Genome Sequence of Streptococcus pneumoniae Strain Rx1, a Hex Mismatch Repair-Deficient Standard Transformation Recipient.

The complete genome sequence of Streptococcus pneumoniae strain Rx1, a Hex mismatch repair-deficient standard transformation recipient, was obtained by combining Nanopore and Illumina sequencing technologies. The genome consists of a 2.03-Mb circular chromosome, with 2,054 open reading frames and a GC content of 39.

Complete Genome Sequence of Lactobacillus crispatus Type Strain ATCC 33820.

The complete genome sequence of Lactobacillus crispatus type strain ATCC 33820 was obtained by combining Nanopore and Illumina sequencing technologies. The genome consists of a 2.2-Mb circular chromosome with 2,194 open reading frames and an average GC content of 37.

Modulation of Cervicovaginal Drug Transporters and Tissue Distribution by Film-Released Tenofovir and Darunavir for Topical Prevention of HIV-1.

Clinical trials have demonstrated partial protection against HIV-1 infection by vaginal microbicide formulations based on antiretroviral (ARV) drugs. Improved formulations that will maintain sustained drug concentrations at viral target sites in the cervicovaginal mucosa are needed. We have previously demonstrated that treatment of cervicovaginal cell lines with ARV drugs can alter gene expression of drug transporters, suggesting that the mucosal disposition of ARV drugs delivered vaginally can be modulated by drug transporters.

Interferon-γ from Brain Leukocytes Enhances Meningitis by Type 4 Streptococcus pneumoniae.

Streptococcus pneumoniae is the leading cause of bacterial meningitis. Pneumococcal meningitis is a life-threatening disease with high rates of mortality and neurological sequelae. Immune targeting of S.

New fluoroquinolones active against fluoroquinolones-resistant Mycobacterium tuberculosis strains.

A set of 21 new fluoroquinolones bearing an aromatic or heteroaromatic moiety at C-7 and an alkyl group at N-1 were synthesized based on the lead structure of pirfloxacin and tested in vitro against Mycobacterium tuberculosis (M. tuberculosis) H37Rv by MIC determination in liquid medium. Among the synthesized compounds, 1-(tert-butyl)-6-fluoro-7-(4-hydroxyphenyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (2o) and 1-(tert-butyl)-6-fluoro-7-(pyridin-3-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (2n) were found to be the most active ones against M.

Sex-based differences in susceptibility to respiratory and systemic pneumococcal disease in mice.

Systemic infection with Streptococcus pneumoniae was investigated in male and female mice in models of invasive pneumonia and sepsis. Male mice were found to be more susceptible to infection, exhibiting greater weight loss, marked decrease in body temperature, and a significantly higher mortality rate compared with female mice. For pneumonia, there were significant differences in survival rates.

Stimulation of human monocytes with the gram-positive vaccine vector Streptococcus gordonii.

Streptococcus gordonii is a bacterial vaccine vector which has previously been shown to activate dendritic cells in vitro and to induce local and systemic immune responses in vivo. In the present study, human monocytes (THP-1 cell line and peripheral blood monocytes) were characterized following interaction with S. gordonii.

In vivo activation of naive CD4+ T cells in nasal mucosa-associated lymphoid tissue following intranasal immunization with recombinant Streptococcus gordonii.

The antigen-specific primary activation of CD4+ T cells was studied in vivo by adoptive transfer of ovalbumin-specific transgenic T cells (KJ1-26+ CD4+) following intranasal immunization with recombinant Streptococcus gordonii. A strain of S. gordonii expressing on its surface a model vaccine antigen fused to the ovalbumin (OVA) peptide from position 323 to 339 was constructed and used to study the OVA-specific T-cell activation in nasal mucosa-associated lymphoid tissue (NALT), lymph nodes, and spleens of mice immunized by the intranasal route.