Parabacteroides absconsus sp. nov., isolated from feces of a child with atopic dermatitis

An obligate anaerobic, Gram-negative rod-shaped bacterial strain designated AD58^T was isolated from the feces of a 3-year-old boy with atopic dermatitis. The closest species is Parabacteroides fecalis with 96.98% 16S rRNA gene identity. The average nucleotide identity value between AD58^T and P. fecalis AGMB00274^T is 85.0-85.4%. The circular genome sequence is 3.77 Mbp long with 43.5 mol% G + C content. The strain AD58^T grows at 32-42 °C, its pH range for growth is 6.0-7.5. No growth is observed in the presence of 1% or higher NaCl concentrations. The major fatty acids are anteiso-C15: 0, iso-C15: 0, and summed feature 11 (iso-C17: 0 3-OH and/or C18: 2 DMA), and the predominant respiratory quinone is MK-9. Conditioned media from AD58^T increased expression of IL-8 but decreased expression of TLR-4 in HT29 cells. Based on the described properties, we propose AD58^T as the type strain of Parabacteroides absconsus sp. nov. (= VKM B-3630^T = JCM 35468^T).