First record of the rare species Aeromonas schubertii from mussels: phenotypic and genetic reevaluation of the species and a review of the literature

Abstract

In a study where the prevalence of Aeromonas in shellfish was analysed, three isolates of Aeromonas schubertii were identified, representing this the first report of this species from mussels. This species was originally described in 1988 from strains isolated from extra-intestinal human infections and since then has been cited in only 18 occasions. For many years, A. schubertii was the only mannitol-negative species of the genus. However, three additional mannitol-negative species (Aeromonas simiae, Aeromonas diversa and Aeromonas australiensis) have been described. This, together with the fact that A. schubertii is a rare human pathogenic species, motivated the present study to characterize its biochemical behaviour and differentiation from the other mannitol-negative species. The molecular similarity (16S rRNA, rpoD and gyrB genes) of the strains, presence of virulence genes and antimicrobial resistance were determined. All A. schubertii strains showed the same phenotypic behaviour, i.e. they use citrate, are positive for lysine decarboxylase and DL-lactate, but negative for production of mannitol, indole and acid from sucrose and could be easily differentiated from other mannitol-negative species. All strains carried the aerA and lafA virulence genes and showed susceptibility to all antibiotics tested. Seafood could be a transmission route of this bacterium to humans.

Species Distribution and Prevalence of Putative Virulence Factors in Mesophilic Aeromonas spp. Isolated from Fresh Retail Sushi

“…The widespread occurrence of Aeromonas ssp. in fish and seafood, vegetables, meat, poultry, raw milk, and different water sources has been confirmed by others (Villari et al, 2000; Kingombe et al, 2004; Heaton and Jones, 2008; Xanthopoulos et al, 2010; Ottaviani et al, 2011; Carvalho et al, 2012; Latif-Eugenín et al, 2016). …”

Aeromonas shuberti as a cause of multi‐organ necrosis in internal organs of Nile tilapia, Oreochromis niloticus

“…(Kokka, Lindquist, Abbott, & Janda, 1992). However, this species has been frequently found from aquatic organisms in recent years, including frog (Pearson, Hirono, Aoki, Miranda, & Inglis, 2000), snakehead fish (Chen et al, 2012;Liu et al, , 2016, shrimps (Yano et al, 2015), mussels (Latif-Eugenin, Beaz-Hidalgo, & Figueras, 2016) and tilapia (this study). Aquatic products may become a transmission route of this bacterium to humans, which certainly deserves our attention and concerns.…”

Chironomids’ Relationship with Aeromonas Species

“…The following species are the most abundant in clinical samples: Aeromonas caviae (29.9%), A. dhakensis (25.5%), A. veronii (22%), and A. hydrophila (18%; Figueras and Beaz-Hidalgo, 2015 ). Among others, less frequently isolated clinical species are A. schubertii , A. simiae , A. diversa, A. taiwanensis, A. sanarellii , A. media , and A. salmonicida ( Janda and Abbott, 2010 ; Beaz-Hidalgo et al, 2012 ; Senderovich et al, 2012 ; Latif-Eugenín et al, 2016 ).…”