The emergence of multidrug-resistant Proteus vulgaris infection in cage reared Pangasianodon hypophthalmus: molecular characterization and host-pathogen response

• Published in: Microbial pathogenesis Vol. 197; p. 107029
• Main Authors: Das, Basanta Kumar, Kumar, Vikash, Baitha, Raju, Ramteke, Mitesh H., Adhikari, Anupam, Bisai, Kampan, Jana, Asim K., Das, Archan Kanti
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 17.10.2024
• Subjects: cage aquaculture; Disease outbreak; P. hypophthalmus; Proteus vulgaris, emerging pathogen; P. hypophthalmus; Disease outbreak; cage aquaculture; Proteus vulgaris, emerging pathogen
• ISSN: 0882-4010; 1096-1208; 1096-1208
• DOI: 10.1016/j.micpath.2024.107029

The study investigates the causative agent responsible for massive mortality in Pangasianodon hypophthalmus cage farms. The infected pangasius were lethargic, not taking feed, and had exophthalmia, deep ulceration, and hemorrhage on the ventral body surface. Pathogens were isolated from infected pangasius tissue samples, and the strain was preliminarily identified as Proteus vulgaris based on morphology, biochemical tests, 16S rRNA PCR sequencing, and phylogenetic analysis. The microbiological analysis revealed that P. vulgaris was associated with the disease outbreak and mortality of P. hypophthalmus, as confirmed by the biofilm formation, swimming activity, and survival assay results . The isolated P. vulgaris was resistant to several antibiotics, including Doxycycline, Dicloxacillin, Polymyxin B, Chloramphenicol, and Imipenem, exhibiting multiple antibiotic-resistant phenotypes. Furthermore, a host-pathogen model was developed to investigate the in vivo effect of emerging P. vulgaris infection in striped catfish. Results showed that P. vulgaris infection exhibited varying degrees of cellular changes in the kidney, liver, and gill tissues of infected P. hypophthalmus samples. The transcription analysis further highlights that P. vulgaris modulates the antioxidants, immune activation, growth regulator, homeostasis, degradation of invading DNA, and DNA damage-related gene expression in liver, kidney, spleen, skin, and gill tissue samples of infected P. hypophthalmus. The lessons learned from the study could be critical in understanding the P. vulgaris infection patterns and pathobiology necessary to enable risk assessment and develop management measures to control the bacterium's virulence. •Multidrug-resistant P. vulgaris isolated from P. hypophthalmus responsible for massive disease outbreaks in cage farm•P. vulgaris displayed higher in vitro and in vivo virulence marked by increased biofilm and swimming motility and mortality and cellular changes in P. hypophthalmus•P. vulgaris infection modulates the gene expression in the liver, kidney, spleen, skin, and gill tissue samples of P. hypophthalmus.•First study describing P. vulgaris as a causative agent for disease outbreaks in P. hypophthalmus