Isolation and Identification of Luminescent Bacteria in Deep Sea Marine Organisms from Sicilian Waters (Mediterranean Sea)

Abstract

Luminescent bacteria are a fascinating component of marine microbial communities, often related to the light emissions in deep sea marine organisms. They are mainly affiliated with specific phylogenetic groups, such as Photobacterium, Vibrio, and Photorhabdus, and are sometimes involved in symbiotic relationships. However, the luminescence of some marine organisms remains a poorly understood process, and it is not always certain whether their luminescence is attributable to associated luminescent bacteria. In this study, for the first time, luminescent bacteria were isolated from two deep sea organisms, namely, the cephalopod Neorossia caroli and the teleost Chlorophthalmus agassizi. The isolation was carried out on glycerol-supplemented medium, and the search for the luxAB gene was performed on all isolates as a complementary tool to the culture-dependent techniques to detect bioluminescence by molecular approach. The optimum of salinity, temperature, and pH was evaluated by physiological tests for all isolates. The production of extracellular polymeric substances was also preliminarily screened. A total of 24 luminescent isolates were obtained, with an abundance from C. agassizi specimens. All the isolates were taxonomically characterized and were related to different species of Photobacterium, with the exception of Vibrio sp. CLD11 that was from C. agassizi. The luxAB gene was detected in about the 90% of the analysed strains.

16S rRNA Gene Amplicon Sequencing of the Gut Microbiota of Chimaera phantasma (Silver Chimaera) Captured off Koshimoda in Suruga Bay, Japan

“…1 ), comprising 89.2% Photobacterium and 2.3% Shewanella species. Photobacterium species are luminous, halophilic, Gram-negative species that are present in the gut of deep-sea fish ( 12 ). Shewanella species are barotropic, luminous, Gram-negative species that are found in oceans ( 13 – 15 ).…”

Bioluminescence in cephalopods: biodiversity, biogeography and research trends

“…Interestingly, as in Sepioteuthis lessoniana, bioluminescent bacteria have been identified in a sepiolid species that is considered non-luminescent. Neorossia caroli lacks a light organ (Sanchez et al, 2021;Calogero et al, 2022); yet bioluminescent bacteria (Photobacterium kishitanii and P. leiognathi) were found in samples taken from the siphon and the mantle (Calogero et al, 2022). The relationships between the non-luminous cephalopods S. lessoniana and N. caroli and the respective bioluminescent bacteria found, in terms of light production, would then be facultative rather than obligate (Zari et al, 2020;Calogero et al, 2022).…”

“…Neorossia caroli lacks a light organ (Sanchez et al, 2021;Calogero et al, 2022); yet bioluminescent bacteria (Photobacterium kishitanii and P. leiognathi) were found in samples taken from the siphon and the mantle (Calogero et al, 2022). The relationships between the non-luminous cephalopods S. lessoniana and N. caroli and the respective bioluminescent bacteria found, in terms of light production, would then be facultative rather than obligate (Zari et al, 2020;Calogero et al, 2022). However, no studies have yet investigated such associations for purposes other than bioluminescence.…”

Biodiversity, Adaptation Strategies, and Opportunities in Extreme Marine Environments

“…Twenty of these isolates were pigmented, and it was suggested that these pigments could help them to survive in Antarctic low temperatures and harmful levels of UV radiation. Meanwhile, in their work, Calogero et al [2] focused on luminescent bacteria isolated, for the first time, from the cephalopod Neorossia caroli and the teleost Chlorophthalmus agassizi from deep sea environment. The authors obtained twenty-four luminescent isolates and also investigated their biotechnological potential by studying the production of extracellular polymeric substances (EPSs).…”