Isolation and phylogenetic analysis of bacteria with antimicrobial activities from the Mediterranean sponges Aplysina aerophoba and Aplysina cavernicola

Abstract

The aim of this study was to isolate bacteria with antimicrobial activities from the marine sponges Aplysina aerophoba and Aplysina cavernicola. The obtained 27 isolates could be subdivided into eight phylogenetically different clusters based on comparative sequence analysis of their 16S rDNA genes. The sponge isolates were affiliated with the low (Bacillus) and high G+C Gram-positive bacteria (Arthobacter, Micrococcus), as well as the alpha-Proteobacteria (unknown isolate) and gamma-Proteobacteria (Vibrio, Pseudoalteromonas). One novel Bacillus species was identified and two species were closely related to previously uncharacterized strains. Isolates with antimicrobial activity were numerically most abundant in the genera Pseudoalteromonas and the alpha-Proteobacteria. The sponge isolates show antimicrobial activities against Gram-positive and Gram-negative reference strains but not against the fungus Candida albicans. A general pattern was observed in that Gram-positive bacteria inhibited Gram-positive strains while Gram-negative bacteria inhibited Gram-negative isolates. Antimicrobial activities were also found against clinical isolates, i.e. multi-resistant Staphylococcus aureus and Staphylococcus epidermidis strains isolated from hospital patients. The high recovery of strains with antimicrobial activity suggests that marine sponges represent an ecological niche which harbors a hitherto largely uncharacterized microbial diversity and, concomitantly, a yet untapped metabolic potential.

Isolation, cytotoxic activity and phylogenetic analysis of <i>Bacillus sp.</i> bacteria associated with the red sea sponge <i>Amphimedon ochracea</i>

“…(firmicutes) (Figure 7). Interestingly, the firmicutes have been reported from diverse marine sponges irrespective of their taxonomic identity, geographic location, or natural products profile [33,34]. The isolates HA-68, HA-MS-105 and HAMS-119 revealed species-level similarity to Bacillus subtilis, Bacillus safensis and Lactobacillus murinus, respectively.…”

“…Company (Tübingen, Germany). The sequences were compared with known sequences in the GenBank nucleotide database and the species level was identified as the nearest phylogenetic neighbor with 98% -100% similarity [29]. Sequence alignment and phylogenetic analysis were performed using the Mega-5 software package [30].…”

Production of Protease Showing Antibacterial Activity by Bacillus subtilis VCDA Associated with Tropical Marine Sponge Callyspongia diffusa

“…The association or involvement of microorganisms may be suspected when the diverse sponge metabolites are purified from taxonomically diverse species or when the production of metabolite is low from the sponge of interest [1]. One of the most effective methods of discovering natural products is the cultivation of new microbial strains that may represent a novel important chemotype [2,3].…”

“…There are several reports and hypothesis that insists that the symbiotic bacteria associated with the sponge are the original producers of bioactive compounds [4,5]. The actual proof for the contribution of microorganisms in secondary metabolism of sponges can be provided if the microbes produce the compound of interest under laboratory conditions [1]. Antimicrobial compounds are produced in conditions like competitions for sharing ecological niche, prevention of phagocytosis, establishment of symbiotic association with invertebrates [6,7].…”

Sponge growth on the Cenomanian carbonate shelves of the Carpathian Basin: a record from spicule-rich turbidites

“…Demosponges are able to live associated, either commensally or symbiotically, with bacteria or on the metabolic products of the bacteria. Bacterial symbionts may play a role in the acquisition and defence of their host sponge (Hentschel et al 2001). Sponges may harbour large amounts of bacteria in their tissues that can amount to 40% of their biomass (Vacelet 1975).…”