Actinomycetes from Sediments in the Trondheim Fjord, Norway: Diversity and Biological Activity

Marine Drugs

Harald Bredholt²  Espen Fjærvik¹  Geir Johnsen³ 

[1] Department of Biotechnology, Norwegian University of Science and Technology, 7491 Trondheim, Norway;Alpharma AS, Harbitzaleen 3, 0275 Oslo, Norway;Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway

关键词: Actinomycete bacteria;    fjord sediments;    molecular taxonomy;    antimicrobial activities;   

DOI  :  10.3390/md6010012

来源: mdpi

【 摘 要 】

The marine environment represents a largely untapped source for isolation of new microorganisms with potential to produce biologically active secondary metabolites. Among such microorganisms, Gram-positive actinomycete bacteria are of special interest, since they are known to produce chemically diverse compounds with a wide range of biological activities. We have set out to isolate and characterize actinomycete bacteria from the sediments in one of the largest Norwegian fjords, the Trondheim fjord, with respect to diversity and antibiotic-producing potential. Approximately 3,200 actinomycete bacteria were isolated using four different agar media from the sediment samples collected at different locations and depths (4.5 to 450 m). Grouping of the isolates first according to the morphology followed by characterization of isolates chosen as group representatives by molecular taxonomy revealed that Micromonospora was the dominating actinomycete genus isolated from the sediments. The deep water sediments contained a higher relative amount of Micromonospora compared to the shallow water samples. Nine percent of the isolates clearly required sea water for normal growth, suggesting that these strains represent obligate marine organisms. Extensive screening of the extracts from all collected isolates for antibacterial and antifungal activities revealed strong antibiotic-producing potential among them. The latter implies that actinomycetes from marine sediments in Norwegian fjords can be potential sources for the discovery of novel anti-infective agents.

【 授权许可】

Unknown   
© 2008 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland