Rare actinobacteria isolated from the hypersaline Ojo de Liebre Lagoon as a source of novel bioactive compounds with biotechnological potential

Abstract

The Ojo de Liebre Lagoon is a Marine Protected Area that lies within a UNESCO World Heritage Site and is a critical habitat for important migratory species such as the grey whale and bird species. Unique hypersaline environments, such as the Ojo de Liebre Lagoon, are underexplored in terms of their bacterial and chemical diversity, representing a potential source for new bioactive compounds with pharmacological properties. Actinobacteria are one of the most diverse and prolific taxonomic bacterial groups in terms of marine bioactive compounds. This study aimed to identify the culturable actinobacterial community inhabiting the Lagoon, as well as to test their potential as new sources of anticancer compounds with pharmacological potential. A selective isolation approach focused on spore-forming bacteria from 40 sediment samples generated a culture collection of 64 strains. The 16S rRNA gene analyses identified three phyla in this study, the Actinobacteria, Firmicutes and Proteobacteria, where the phylum Actinobacteria dominated (57%) the microbial community profiles. Within the Actinobacteria, nine different genera were isolated including the Actinomadura, Micromonospora, Nocardiopsis, Plantactinospora and Streptomyces sp. We observed seasonal differences on actinobacteria recovery. For instance, Micromonospora strains were recovered during the four sampling seasons, while Arthrobacter and Pseudokineococcus were only isolated in February 2018, and Blastococcus, Rhodococcus and Streptomyces were uniquely isolated in June 2018. Ethyl acetate crude extracts derived from actinobacterial cultures were generated and screened for cytotoxic activity against six cancer cell lines. Strains showed promising low percentages of viability on lung (H1299), cervical (SiHa), colon (Caco-2) and liver (HepG2) cancer lines. Molecular networking results suggest many of the metabolites produced by these strains are unknown and they might harbour novel chemistry. Our results showed the Ojo de Liebre Lagoon is a novel source for isolating diverse marine actinobacteria which produce promising bioactive compounds for potential biotechnological use as anticancer agents.

Characterization of Bioactive Actinomycetes Isolated from Kadolkele Mangrove Sediments, Sri Lanka

“…can produce industrially important extracellular enzymes such as lipase, cellulase, keratinase, and amylase (Mukhtar et al 2017;Swarna and Gnanadoss 2020). Moreover, new and under-explored habitats such as deserts, biomes, and marine ecosystems are known to be very rich sources of novel actinomycetes, which can produce new bioactive compounds, including antibiotics (Hong et al 2009;Aftab et al 2015;Davies-Bolorunduro et al 2019;Subramani and Sipkema 2019;Zamora-Quintero et al 2022). These enzymes and bioactive compounds are of great value in industrial applications, as many of them possess important properties such as heat tolerance and stability under alkaline conditions (Grover et al 2016;Nandimath et al 2017).…”

Rhodococcus strains as a good biotool for neutralizing pharmaceutical pollutants and obtaining therapeutically valuable products: Through the past into the future

“…Stress-tolerant Rhodococcus spp. thriving in deserts, permafrost, cave ecosystems, the deep sea, animal and human microbiota are of interest ( Ceniceros et al, 2017 ; Jia et al, 2020a ; Meena et al, 2021 ; Wang et al, 2021 ; Zamora-Quintero et al, 2022 ). Thus, polycyclic pluramycin-class polyketides, rausuquinone and hydramycin, were isolated from a deep sea-derived Rhodococcus sp.…”

Computational Drug Designing, Synthesis, Characterization and Anti-bacterial Activity Evaluation of Some Mixed Ligand–Metal Complexes of 2-hydroxybenzaldehydethiosemicarbazone as Primary Ligand

“…One of the main applications of bioinorganic chemistry is the use of metal ions or metal complexes in a biological system for the treatment of various diseases [ 1 ]. The usage of metal complexes in medicine, further encourages additional research into developing novel metallo-medicines including metal-mediated antibiotics, antivirals, antibacterials, antiparasitic [ 2 ], anti-diabetic, radio-sensitizing agents and anti-cancer compounds [ 3 ]. Metal complexes often exhibit greater bioactivities than free ligands [ 4 ] and some adverse effects and medication resistance may be decreased upon complexation [ 5 ].…”