Characterization of Pathogenic Pseudomonas alcaligenes Isolated from Koi Carp in China

Abstract

Pseudomonas alcaligenes infection is rare in aquaculture. In this study, we provide the first report on the characterization of P. alcaligenes from koi (a variant of Common Carp Cyprinus carpio) in China. A gram‐negative bacterium was isolated from the diseased koi and was named KCP‐516. Morphological and biochemical tests as well as phylogenetic tree analyses derived from 16S ribosomal RNA, gyrase subunit A, and gyrase subunit B gene sequencing all strongly indicated that the isolate KCP‐516 was P. alcaligenes. In liquid medium, the optimal growth conditions were 25°C, 2.5% NaCl, and pH 8. The pathogenicity of the isolate was demonstrated in koi, with 7.0 × 104 CFU/g fish weight identified as the dose lethal to 50% of test fish. The results will provide a scientific reference for the diagnosis and treatment of P. alcaligenes infection.

Aaqueous exposure to silver nanoparticles synthesized by abalone viscera hydrolysates promotes the growth, immunity and gut health of zebrafish (Danio rerio)

“…It is abundance in control was as high as 2.55% but significantly decreased to 0.27 and 0.58% in the C2 and C3 groups, respectively. P. alcaligenes is considered to be a conditional pathogen for humans and animals ( Bowman, 2005 ) and could be isolated from diseased Asian Swamp Eel ( Monopterus albus ) ( Ma and Shu, 2000 ), Chinese Sturgeon ( Acipenser sinensis ) ( Xu et al, 2015 ), Large yellow croaker ( Pseudosciaena crocea ) ( Huang et al, 2019 ) and Koi carp ( Cyprinus rubrofuscus ) ( Bai et al, 2021 ). P. alcaligenes is a serious sub-health problem in aquaculture ( Suzuki et al, 2013 ).…”

Gracilaria gracilis and Nannochloropsis oceanica, singly or in combination, in diets alter the intestinal microbiota of European seabass (Dicentrarchus labrax)

“…Although the genus Pseudomonas is often reported as part of the normal microbiota and certain bacteria belonging to this taxa are probiotic strains (Qi et al, 2020), there are also opportunistic fish pathogens among them that are responsible for disease outbreaks and high mortality in farms (Oh et al, 2019). NANGRA-fed fish presented a reduced abundance of an ASV belonging to Pseudomonas that is probably related to P. alcaligenes, a rare but potentially opportunistic fish pathogen (Bai et al, 2021). This microalga also decreased the abundance of the genus Vibrio, one of the most important fish pathogens responsible for devastating economic losses in fish farms.…”

Microbial degradation mechanism of historical silk revealed by proteomics and metabolomics

“…In the present study, artificial degradation of silk was carried out using two selected species of bacteria, Pseudomonas alcaligenes ( P. alcaligenes ), 24 a common soil organism, and Stenotrophomonas maltophilia ( S. maltophilia ), which has been detected in ancient tombs with remarkable abundance. 25,26 Proteomics and morphological observations provide a detailed evaluation of the comprehensive effects of time-dependent degradation.…”