title: Diversity and bioactive potential of endospore-forming bacteria cultured from the marine sponge Haliclona simulans.
abstract: OBJECTIVE
  Despite the frequent isolation of endospore-formers from marine sponges, little is known about the diversity and characterization of individual isolates. The main aims of this study were to isolate and characterize the spore-forming bacteria from the marine sponge Haliclona simulans and to examine their potential as a source for bioactive compounds.
  
  
  RESULTS
  A bank of presumptive aerobic spore-forming bacteria was isolated from the marine sponge H. simulans. These represented c. 1% of the total culturable bacterial population. A subgroup of thirty isolates was characterized using morphological, phenotypical and phylogenetic analysis. A large diversity of endospore-forming bacteria was present, with the thirty isolates being distributed through a variety of Bacillus and Paenibacillus species. These included ubiquitous species, such as B. subtilis, B. pumilus, B. licheniformis and B. cereus group, as well as species that are typically associated with marine habitats, such as B. aquimaris, B. algicola and B. hwajinpoensis. Two strains carried the aiiA gene that encodes a lactonase known to be able to disrupt quorum-sensing mechanisms, and various isolates demonstrated protease activity and antimicrobial activity against different pathogenic indicator strains, including Clostridium perfringens, Bacillus cereus and Listeria monocytogenes.
  
  
  CONCLUSIONS
  The marine sponge H. simulans harbours a diverse collection of endospore-forming bacteria, which produce proteases and antibiotics. This diversity appears to be overlooked by culture-dependent and culture-independent methods that do not specifically target sporeformers.
  
  
  CONCLUSIONS
  Marine sponges are an as yet largely untapped and poorly understood source of endospore-forming bacterial diversity with potential biotechnological, biopharmaceutical and probiotic applications. These results also indicate the importance of combining different methodologies for the comprehensive characterization of complex microbial populations such as those found in marine sponges.
authors: Department of Microbiology, University College Cork, Cork, Ireland.
authors: R W
authors: RW
authors: Phelan
authors: J A
authors: JA
authors: O'Halloran
authors: J
authors: J
authors: Kennedy
authors: J P
authors: JP
authors: Morrissey
authors: A D W
authors: AD
authors: Dobson
authors: F
authors: F
authors: O'Gara
authors: T M
authors: TM
authors: Barbosa
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000378:metabolism / Q000494:pharmacology; D044822:Biodiversity; D004725:Endospore-Forming Bacteria / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D047129:Haliclona / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000890:Anti-Infective Agents; D012336:RNA, Ribosomal, 16S