AUTHOR=Undabarrena Agustina , Beltrametti Fabrizio , Claverías Fernanda P. , González Myriam , Moore Edward R. B. , Seeger Michael , Cámara Beatriz 

TITLE=Exploring the Diversity and Antimicrobial Potential of Marine Actinobacteria from the Comau Fjord in Northern Patagonia, Chile

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.01135

DOI=10.3389/fmicb.2016.01135

ISSN=1664-302X

ABSTRACT=<p>Bioprospecting natural products in marine bacteria from fjord environments are attractive due to their unique geographical features. Although, <italic>Actinobacteria</italic> are well known for producing a myriad of bioactive compounds, investigations regarding fjord-derived marine <italic>Actinobacteria</italic> are scarce. In this study, the diversity and biotechnological potential of <italic>Actinobacteria</italic> isolated from marine sediments within the Comau fjord, in Northern Chilean Patagonia, were assessed by culture-based approaches. The 16S rRNA gene sequences revealed that members phylogenetically related to the <italic>Micrococcaceae, Dermabacteraceae, Brevibacteriaceae, Corynebacteriaceae, Microbacteriaceae, Dietziaceae, Nocardiaceae</italic>, and <italic>Streptomycetaceae</italic> families were present at the Comau fjord. A high diversity of cultivable <italic>Actinobacteria</italic> (10 genera) was retrieved by using only five different isolation media. Four isolates belonging to <italic>Arthrobacter, Brevibacterium, Corynebacterium</italic> and <italic>Kocuria</italic> genera showed 16S rRNA gene identity &lt;98.7% suggesting that they are novel species. Physiological features such as salt tolerance, artificial sea water requirement, growth temperature, pigmentation and antimicrobial activity were evaluated. <italic>Arthrobacter, Brachybacterium, Curtobacterium, Rhodococcus</italic>, and <italic>Streptomyces</italic> isolates showed strong inhibition against both Gram-negative <italic>Pseudomonas aeruginosa, Escherichia coli</italic> and <italic>Salmonella enterica</italic> and Gram-positive <italic>Staphylococcus aureus, Listeria monocytogenes</italic>. Antimicrobial activities in <italic>Brachybacterium, Curtobacterium</italic>, and <italic>Rhodococcus</italic> have been scarcely reported, suggesting that non-mycelial strains are a suitable source of bioactive compounds. In addition, all strains bear at least one of the biosynthetic genes coding for NRPS (91%), PKS I (18%), and PKS II (73%). Our results indicate that the Comau fjord is a promising source of novel <italic>Actinobacteria</italic> with biotechnological potential for producing biologically active compounds.</p>