We have previously shown that intranasal infection of mice with mouse hepatitis virus (MHV) strain UAB (MHV-UAB) increases their resistance to Salmonella typhimurium injected intravenously 6 days later. To study how salmonella resistance was induced, BALB/cAnNCr mice were infected with salmonella strains carrying specific genetic alterations. One set of studies compared the effect of MHV infect...

Oral tolerance to foods can be regulated by microorganisms in the gut lumen. We hypothesized that pretreatment with avirulent Salmonella typhimurium strains could prevent food allergy in mice. Mice were administered S. typhimurium PhoPc (STPhoPc) or S. typhimurium AroA prior to oral sensitization to beta-lactoglobulin in the presence of cholera toxin. An oral antigen challenge after sensitizati...

L-Phenylalanine (L-Phe) is an important amino acid used in both food and medicinal applications. We developed an in vitro system that allowed a direct, quantitative investigation of phenylalanine biosynthesis in E. coli. Here, the absolute concentrations of six enzymes (AroK, AroL, AroA, AroC, PheA and TyrB) involved in the shikimate (SHIK) pathway were determined by a quantitative proteomics a...

Mice defective in the ability to produce the tumor necrosis factor alpha p55 receptor (TNFalphap55R) were orally challenged with a number of Salmonella typhimurium HWSH derivatives that differ in virulence. In comparison to TNFalphap55R+/+ mice, TNFalphap55R-/- mice succumbed earlier to challenge with wild-type S. typhimurium HWSH and S. typhimurium HWSH purE. In contrast, TNFalphap55R-/- mice ...

A temperature-sensitive (TS) plasmid was generated from the endogenous streptomycin resistance plasmid of Mannheimia hemolytica and used to engineer in-frame aroA deletion mutants of Mannheimia hemolytica, Pasteurella multocida, and Haemophilus somnus. TS replacement plasmids carrying in-frame aroA deletions were constructed for each target species and introduced into host cells by electroporat...

PURPOSE Nonsyndromic autosomal recessive optic atrophy (arOA) is extremely rare and its existence was disputed until a locus, optic atrophy 6 (OPA6), was mapped to 8q. Recently, a second locus, OPA7, was found on 11q in several families from North Africa, with one presumably ancestral mutation of transmembrane protein 126A (TMEM126A). Here we report an independently ascertained large consanguin...