A single rare σ70 variant establishes a unique gene expression pattern in the E. coli pathobiont LF82.

LF82, an adherent-invasive Escherichia coli (AIEC) pathobiont, is associated with Crohn's disease, an inflammatory bowel disease of unknown etiology. Although AIEC phenotypes differ from those of 'commensal' or pathogenic E. coli, work has failed to identify genetic features accounting for these differences.

The pathobiont LF82 encodes a unique variant of σ that results in specific gene expression changes and altered phenotypes.

LF82, an adherent invasive pathobiont, is associated with ileal Crohn's disease, an inflammatory bowel disease of unknown etiology. Although LF82 contains no virulence genes, it carries several genetic differences, including single nucleotide polymorphisms (SNPs), that distinguish it from nonpathogenic . We have identified and investigated an extremely rare SNP that is within the highly conserved gene, encoding σ, the primary sigma factor for RNA polymerase.

A phage-encoded nucleoid associated protein compacts both host and phage DNA and derepresses H-NS silencing.

Nucleoid Associated Proteins (NAPs) organize the bacterial chromosome within the nucleoid. The interaction of the NAP H-NS with DNA also represses specific host and xenogeneic genes. Previously, we showed that the bacteriophage T4 early protein MotB binds to DNA, co-purifies with H-NS/DNA, and improves phage fitness.

Effect of testosterone and estrogen supplementation on the resistance to systemic infection in mice.

species are the 4 leading cause of nosocomial infections in the US affecting both men and women. Since males of many species can be more susceptible to infections than females, we investigated whether male mice were more susceptible to systemic () infection and if sex hormones were responsible for sex-dependent susceptibility to this infection. Non-gonadectomized or gonadectomized mice were supplemented with sustained release 5α-dihydrotestosterone (5αDHT) or 17-β-estradiol (E2) using subcutaneous pellet implantation.

The Bacteriophage T4 MotB Protein, a DNA-Binding Protein, Improves Phage Fitness.

The lytic bacteriophage T4 employs multiple phage-encoded early proteins to takeover the host. However, the functions of many of these proteins are not known. In this study, we have characterized the T4 early gene , located in a dispensable region of the T4 genome.

Effect of Delta-9-tetrahydrocannabinol on mouse resistance to systemic Candida albicans infection.

Delta-9-tetrahydrocannabinol (Δ9-THC), the psychoactive component of marijuana, is known to suppress the immune responses to bacterial, viral and protozoan infections, but its effects on fungal infections have not been studied. Therefore, we investigated the effects of chronic Δ9-THC treatment on mouse resistance to systemic Candida albicans (C. albicans) infection.