title: Diversity, ecological distribution and biotechnological potential of Actinobacteria inhabiting seamounts and non-seamounts in the Tyrrhenian Sea.
abstract: In the present study, the ecological distribution of marine Actinobacteria isolated from seamount and non-seamount stations in the Tyrrhenian Sea was investigated. A collection of 110 isolates was analyzed by Automated Ribosomal Intergenic Spacer Analysis (ARISA) and 16S rRNA gene sequencing of representatives for each ARISA haplotype (n=49). Phylogenetic analysis of 16S rRNA sequences showed a wide diversity of marine isolates and clustered the strains into 11 different genera, Janibacter, Rhodococcus, Arthrobacter, Kocuria, Dietzia, Curtobacterium, Micrococcus, Citricoccus, Brevibacterium, Brachybacterium and Nocardioides. Interestingly, Janibacter limosus was the most encountered species particularly in seamounts stations, suggesting that it represents an endemic species of this particular ecosystem. The application of BOX-PCR fingerprinting on J. limosus sub-collection (n=22), allowed their separation into seven distinct BOX-genotypes suggesting a high intraspecific microdiversity among the collection. Furthermore, by screening the biotechnological potential of selected actinobacterial strains, J. limosus was shown to exhibit the most important biosurfactant activity. Our overall data indicates that Janibacter is a major and active component of seamounts in the Tyrrhenian Sea adapted to low nutrient ecological niche.
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia; Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133 Milan, Italy.
authors.forename: Besma
authors.initials: B
authors.lastname: Ettoumi
authors.affiliation: Univ. Manouba, ISBST, BVBGR-LR11ES31, Biotechpole of Sidi Thabet, 2020 Ariana, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Chouchane
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: Amel
authors.initials: A
authors.lastname: Guesmi
authors.affiliation: Univ. Manouba, ISBST, BVBGR-LR11ES31, Biotechpole of Sidi Thabet, 2020 Ariana, Tunisia.
authors.forename: Mouna
authors.initials: M
authors.lastname: Mahjoubi
authors.affiliation: Faculty of Science and Technology, Free University of Bozen/Bolzano, Bolzano, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Brusetti
authors.affiliation: Univ. Manouba, ISBST, BVBGR-LR11ES31, Biotechpole of Sidi Thabet, 2020 Ariana, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Neifar
authors.affiliation: Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133 Milan, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Borin
authors.affiliation: Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133 Milan, Italy; BESE, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Daniele
authors.initials: D
authors.lastname: Daffonchio
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia; Univ. Manouba, ISBST, BVBGR-LR11ES31, Biotechpole of Sidi Thabet, 2020 Ariana, Tunisia. Electronic address: cherif.ameur@gmail.com.
authors.forename: Ameur
authors.initials: A
authors.lastname: Cherif
mesh_terms: D039903:Actinobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D044822:Biodiversity; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D005838:Genotype; D019015:Geologic Sediments / Q000382:microbiology*; D019083:Mediterranean Region; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S
keywords: ARISA fingerprinting; Actinobacteria; BOX-PCR; Biosurfactant; Deep sea sediments