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A novel Gram-stain-positive, aerobic, catalase-positive, oxidase-negative, non-motile, and rod-shaped bacterium with ibuprofen-degrading capacity, designated DM4 T , was isolated from the sewage of a wastewater treatment plant (WWTP) in Guangzhou city, China. Strain DM4 T grew optimally at 0% (w/v) NaCl, pH 5.0-7.0, and 30 °C, forming white colonies on trypticase soy agar. C 18:1 ω9c, C 18:2 ω9.12c and C 15:1 ω10c were the predominant fatty acids. Results of 16S rRNA gene alignment and phylogenetic analysis indicated that strain DM4 T belonged to the genus Patulibacter, was closely related to Patulibacter medicamentivorans DSM 25692 T (98.5%) and P. brassicae KCTC 39817 T (98.1%). Strain DM4 T had a genome size of 5.33Mbp, and the DNA G + C content was 75.0%. The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridisation (dDDH) values between strain DM4 T and P. medicamentivorans were 85.2%, 83.9%, and 29.0% respectively, while those between strain DM4 T and P. brassicae were 78.5%, 71.3%, and 22.2%, respectively. Strain DM4 T could significantly degrade ibuprofen by almost 80% after 84 h of incubation, and the degradation kinetics was well fitted with the first-order kinetics. Evidence from phenotypic, phylogenetic and chemotaxonomic analyses support that strain DM4 T (= GDMCC 1.4574 T  = KCTC 59145 T ) represents a new species of the genus Patulibacter, for which the name Patulibacter defluvii sp. nov. is proposed., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Edwardsiella tarda, an enteric opportunistic pathogen, is associated with acute to chronic edwardsiellosis in cultured fish, resulting in heavy losses in aquaculture. To date, the pathogenesis of E. tarda has been extensively studied and a great deal of vaccine candidates have been attempted. However, the research on the predisposition of E. tarda infection is poorly reported. In this study, the effects of intestinal inflammation on E. tarda infection were investigated using a zebrafish model that influenced by perturbation of intestinal microbiota. Featured symptoms of edwardsiellosis were observed in intestinal inflammatory zebrafish compared with healthy fish. Higher bacterial numbers were detected in both mucosal tissues (intestine, skin and gills) and lymphoid tissues (liver, spleen and kidney) of inflammatory zebrafish while the bacterial loads in healthy zebrafish appeared to be relatively lower by 10-100 folds. Moreover, significant up-regulation of IL-1β, TNF-α and iNOS was noticed in multiple tissues of zebrafish with intestinal inflammation between 6 and 72 h post infection. However, only moderate elevation was observed in the gills and liver of healthy fish. Furthermore, the expression of genes involved in neutrophil recruitment (mpx, IL-8 and LECT2) and antimicrobial response (β-defensin and hepcidin) showed notable up-regulation in the intestine of inflammatory zebrafish. These results demonstrate that fish with intestinal inflammation is more susceptible to E. tarda and the antimicrobial response during E. tarda infection might inhibit the growth of intestinal microbiota. Our results suggest that maintaining good management to avoid intestinal inflammation is a feasible prevention measure against edwardsiellosis., (Copyright © 2014 Elsevier Ltd. All rights reserved.)