Producing mechanism of an algicidal compound against red tide phytoplankton in a marine bacterium γ-proteobacterium

Takuji Nakashima*, Yousuke Miyazaki, Yukihiko Matsuyama, Wataru Muraoka, Kenichi Yamaguchi, Tatsuya Oda

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

101 Citations (Scopus)


Strain MS-02-063, γ-proteobacterium, isolated from a coast area of Nagasaki, Japan, produced a red pigment which belongs to prodigiosin members. This pigment, PG-L-1, showed potent algicidal activity against various red tide phytoplanktons in a concentration-dependent manner. An understanding of a mechanism of PG-L-1 production by this marine bacterium may yield important new insights and strategies for preventing blooms of harmful flagellate algae in natural marine environments. Therefore, we analyzed the mechanisms of PG-L-1 production. In our previous study, the pigment production by this marine bacterium was completely inhibited at 1.56 μg/ml of erythromycin or 3.13 μg/ml of chloramphenicol, while minimal inhibitory concentrations for cell growth of erythromycin and chloramphenicol against this bacterium were >100 and 25 μg/ml, respectively. It is interesting to note that the ability of the pigment production in erythromycin-treated bacterium recovered by an addition of homoserine lactone. In fact, the pigment production was inhibited by β-cyclodextrin that inhibits autoinducer activities by a complex with N-acyl homoserine lactones. N-acyl homoserine lactones with autoinducer activities are ubiquitous bacterial signaling molecules that regulate gene expression in a cell density dependent process known as quorum sensing. Therefore, it was suggested that PG-L-1 produced by strain MS-02-063 is controlled by the homoserine lactone quorum sensing. It is speculated that this quorum sensing is involved in the production of algicidal agents of other marine bacteria. This bacterium and other algicidal bacteria might be concerned in regulating the blooms of harmful flagellate algae through the quorum sensing system.

Original languageEnglish
Pages (from-to)684-690
Number of pages7
JournalApplied Microbiology and Biotechnology
Issue number3
Publication statusPublished - 2006 Dec
Externally publishedYes


  • γ-proteobacterium
  • Algicidal activity
  • Harmful algal bloom
  • Homoserine lactone
  • Prodigiosin

ASJC Scopus subject areas

  • Biotechnology
  • Applied Microbiology and Biotechnology


Dive into the research topics of 'Producing mechanism of an algicidal compound against red tide phytoplankton in a marine bacterium γ-proteobacterium'. Together they form a unique fingerprint.

Cite this