Nontypeable Haemophilus influenzae gene expression induced in vivo in a chinchilla model of otitis media.

摘要: The gram-negative bacterium nontypeable Haemophilus influenzae (NTHI) is the predominant pathogen in chronic otitis media with effusion and, Streptococcus pneumoniae and Moraxella catarrhalis, a causative agent of acute media. To identify potential virulence determinants, bacterial gene expression was monitored by differential fluorescence induction during early disease progression one specific anatomical niche chinchilla model NTHI-induced Genomic DNA fragments from NTHI strain 86-028NP were cloned upstream promoterless gfpmut3 gene. served as host for promoter trap library. Pools 2,000 transformants inoculated into left right middle ear cavities chinchillas. Middle effusions recovered epitympanic tap at 24 48 h, clones containing elements that induced vivo producing green fluorescent protein isolated two-color fluorescence-activated cell sorting. Insert sequenced compared to complete genome sequence H. Rd. In screen 16,000 clones, we have 44 contain unique encoding biosynthetic enzymes, metabolic regulatory proteins, hypothetical proteins unknown function. An additional eight our isolate. Using quantitative reverse transcription-PCR, confirmed 26 demonstrated increased relative vitro. These data provide insight response bacteria they sense respond microenvironment events