Phylogenetic distribution of roseobacticides in the Roseobacter group and their effect on microalgae

Eva C. Sonnenschein, Christopher Broughton William Phippen, Mikkel Bentzon-Tilia, Silas Anselm Rasmussen, Kristian Fog Nielsen, Lone Gram*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

90 Downloads (Pure)


The Roseobacter-group species Phaeobacter inhibens produces the antibacterial tropodithietic acid (TDA) and the algaecidal roseobacticides with both compound classes sharing part of the same biosynthetic pathway. The purpose of this study was to investigate the production of roseobacticides more broadly in TDA-producing roseobacters and to compare the effect of producers and non-producers on microalgae. Of 33 roseobacters analyzed, roseobacticide production was a unique feature of TDA-producing P. inhibens, P. gallaeciensis and P. piscinae strains. One TDA-producing Phaeobacter, 27-4, did not produce roseobacticides, possibly due to a transposable element. TDA-producing Ruegeria and Pseudovibrio did not produce roseobacticides. Addition of roseobacticide-containing bacterial extracts affected the growth of the microalgae Rhodomonas salina, Thalassiosira pseudonana and Emiliania huxleyi, while growth of Tetraselmis suecica was unaffected. During co-cultivation, growth of E. huxleyi was initially stimulated by the roseobacticide producer DSM 17395, while the subsequent decline in algal cell numbers during senescence was enhanced. Strain 27-4 that does not produce roseobacticides had no effect on algal growth. Both bacterial strains, DSM 17395 and 27-4, grew during co-cultivation presumably utilizing algal exudates. Furthermore, TDA-producing roseobacters have potential as probiotics in marine larviculture and it is promising that the live feed Tetraselmis was unaffected by roseobacticides-containing extracts.
Original languageEnglish
JournalEnvironmental Microbiology Reports
Issue number3
Pages (from-to)383-393
Publication statusPublished - 2018


Dive into the research topics of 'Phylogenetic distribution of roseobacticides in the Roseobacter group and their effect on microalgae'. Together they form a unique fingerprint.

Cite this