Characterization of putative pathogenic Shewanella algae isolated from ballast water

Abstract

Background and Aim: Shewanella algae is ubiquitous in marine-associated environments and has been increasingly recognized as a significant human pathogen that can cause serious infections mainly associated with exposure to seawater and ingestion of raw seafood. This study aimed to isolate and characterize S. algae from ballast water of ships berthed at Port Klang, Malaysia. Materials and Methods: Ballast water was sampled from nine ships docked at Port Klang, Malaysia. The isolates were identified and characterized based on biochemical and enzymatic properties, 16S rRNA and gyrB sequencing, biofilm formation capability, and antibiotic susceptibility. Results: A total of four S. algae isolates were isolated from four ballast water samples tentatively name Sa-BW1, Sa-BW2, Sa-BW7, and Sa-BW8. All isolates showed positive reaction for cytochrome oxidase, catalase, high tolerance to NaCl (6% and 8%), ability to grow at 42°C, and on Salmonella-Shigella agar. The strains also exhibited β-hemolytic activity on sheep blood and human blood agar, positive reaction for lipase, protease, DNase and gelatinase, strong biofilm adherence capabilities and multiple antibiotic resistances against ampicillin, carbenicillin, cephalothin, colistin, novobiocin, oxacillin, penicillin, rifampicin, and tobramycin which suggested their potential pathogenicity. Conclusion: This study demonstrated the occurrence of putative pathogen S. algae in ballast water of ships docked at Malaysian port.

Investigation of antibiotic-resistant vibrios associated with shrimp (Penaeus vannamei) farms

“…Nevertheless, their antimicrobial resistance pattern indicated that the prevalence of such least reported bacteria also play a key role in spreading AMR among the shrimp pathogens. Higher MAR index of putative pathogen, S. algae was recently reported from marine environments also corroborated with the present study (Ibrahim et al 2021). Even though diverse bacteria were recovered and an overall increased AMR and uniform resistance pattern were observed among the samples from farm 2 compared to farm 1, the MAR index was found to be higher in the case of farm 1 with V. alginoyliticus and V. mimicus as the most resistant ones.…”

Gut Microbial Characterization of Melon-Headed Whales (Peponocephala electra) Stranded in China

“…Furthermore, the ASVs were all annotated as Shewanella algae . Shewanella algae is ubiquitous in the marine environments and has been identified as conditionally pathogenic bacteria that can cause serious infections, primarily associated with exposure to seawater and ingestion of raw seafood, and this group of bacteria can exhibited b-hemolytic activity, strong biofilm-adherence capabilities, and multiple antibiotic resistances [ 37 , 38 , 39 , 40 , 41 , 42 ]. We think that Shewanella algae should not be a dominant group (though it can be present) in melon-headed whales or short-finned pilot whales [ 16 ]; indeed, the overwhelming dominance of Shewanella algae in the gut of PE8 might have been a potential trigger of its death ( Figure 3 ).…”

Unveiling the Emergence and Genetic Diversity of OXA-48-like Carbapenemase Variants in Shewanella xiamenensis

“…Since the discovery of the first bla OXA-48 gene in Klebsiella pneumoniae in Istanbul in 2001, there has been a growing number of carbapenem-hydrolyzing class D β-lactamases (CHDLs) found globally [ 7 , 8 , 9 , 10 , 11 ]. Furthermore, an increasing number of OXA-48-like variants capable of carbapenem hydrolysis have been identified in both the clinical and community settings [ 12 , 12 , 13 , 14 , 15 , 16 ]. As carbapenems are considered last-resort antimicrobials in the treatment of Gram-negative bacterial infections, the emergence and spread of OXA variants has garnered significant attention because of the potential risks they present in clinical infection management.…”

“…strains are closely associated with human diseases [ 7 , 8 , 9 , 10 ]. The common pathogenic species of Shewanella , including Shewanella xiamenensis , Shewanella algae , and Shewanella putrefaciens [ 11 , 12 ], are derived from various environments such as saltmarsh plants, freshwater, estuarine water, sewage, river water and livestock wastewater [ 12 , 13 , 14 , 15 , 16 , 17 ]. According to the latest clinical reports, skin and soft tissue infections, intestinal colonization, respiratory diseases, bacteremia, intra-abdominal infection, and otitis media are the common complications caused by Shewanella spp.…”