Nasal carriage of Staphylococcus aureus and endonasal activity in Wegener’s granulomatosis as compared to rheumatoid arthritis and chronic rhinosinusitis with nasal polyps

Objectives: nasal colonisation with Staphylococcus aureus (S. aureus) has been implicated in Wegener`s granulomatosis (WG) disease activity. In this study, the frequency of nasal colonisation with S. aureus in WG was compared to healthy and disease control groups for the first time. Moreover, endonasal activity was correlated to colonisation.Patients and methods: nasal carriage of S. aureus of a well-defined group of 89 patients with WG was compared to 40 patients with chronic rhinosinusitis with nasal polyps (CRS), 35 patients with rheumatoid arthritis (RA), 50 hospital staff members and 25 subjects without regular hospital contact and correlation analysis of nasal carriage and endonasal activity of WG was performed. Results: WG patients showed significantly higher rates (72%) of nasal colonisation with S. aureus compared to CRS patients (28%) and healthy subjects without regular hospital contact (25%, 95%-CI), but not to RA patients (46%) and hospital staff members (58%). WG patients with nasal carriage of S. aureus had significantly higher endoscopically proven endonasal activity (p=0.01), significantly more often first manifestation of WG in the upper respiratory tract (p=0.02) and higher relapse-rates (p=0.052) than WG patients without such carriage. Conclusions: endonasal activity in WG is associated with higher nasal S. aureus colonisation rates and subsequent higher relapse rates. The higher frequency of S. aureus colonisation could be a consequence of a recently shown mucosal barrier defect in WG and facilitate chronic inflammation and granuloma formation in the upper respiratory tract

Four promoters subject to regulation by ExoR and PhoB direct transcription of the Sinorhizobium meliloti exoYFQ operon involved in the biosynthesis of succinoglycan

Quester I, Becker A. Four promoters subject to regulation by ExoR and PhoB direct transcription of the Sinorhizobium meliloti exoYFQ operon involved in the biosynthesis of succinoglycan. JOURNAL OF MOLECULAR MICROBIOLOGY AND BIOTECHNOLOGY. 2004;7(3):115-132.Succinoglycan (EPS I), the main acidic exopolysaccharide of Sinorhizobium meliloti, is required for the initiation and elongation of infection threads during nodulation of the host plant alfalfa. The gene products of the exoYFQ operon are involved in the first step of succinoglycan biosynthesis as well as in the polymerisation of subunits to the high-molecular-mass form of this exopolysaccharide. One promoter region that directs transcription of exoX and two promoter regions that drive transcription of exoY were mapped in the exoX-exoY intergenic region. The distal exoY promoter region containing three putative -10 promoter elements was active under standard growth conditions and was subject to ExoR-dependent regulation. Although this promoter region was stimulated in a phoB mutant, no PHO box-like sequences were found, suggesting an indirect regulatory effect of PhoB. The proximal promoter contains a PHO box-like sequence in the putative - 35 region and was affected by low and high phosphate concentrations dependent on PhoB. In the case of deleted upstream regions, this promoter was also controlled by ExoR. An additional promoter displaying activity in exoR, mucR and phoB mutants under standard conditions was identified upstream of exoF. The putative - 35 promoter element of this promoter is covered by a second PHO boxlike sequence. Copyright (C) 2004 S. Karger AG, Basel