title: The use of fosmid metagenomic libraries in preliminary screening for various biological activities.
abstract: BACKGROUND
  It is generally believed that there are many natural sources of as yet unknown bioactive compounds with a high biotechnological potential. However, the common method based on the use of cell extracts in the preliminary screening for particular molecules or activities is problematic as amounts of obtained compounds may be low, and such experiments are hardly reproducible. Therefore, the aim of this work was to test whether a novel strategy to search for previously unknown biological activities can be efficient. This strategy is based on construction of metagenomic libraries and employment of Escherichia coli strains as cell factories producing compounds of properties potentially useful in biotechnology.
  
  
  RESULTS
  Three cyanobacterial metagenomic libraries were constructed in the fosmid system. The libraries were screened for various biological activities. Extracts from selected E. coli clones bearing constructs with fragments of cyanobacterial genomes revealed antimicrobial or anticancer activities. Interestingly, stimulation of growth of host bacteria bearing particular plasmids with certain cyanobacterial genes was detected, suggesting a potential possibility for improvement of E. coli cultivation during biotechnological production. The most interesting plasmids were sequenced, and putative mechanisms of biological effects caused by cyanobacterial gene products are discussed.
  
  
  CONCLUSIONS
  The strategy of exploring cyanobacteria as sources of bioactive compounds, based on E. coli cell factories producing compounds due to expression of genes from metagenomic libraries, appears to be effective.
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. agnieszka.felczykowska@biol.ug.edu.pl.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Felczykowska
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. ola.dydecka@wp.pl.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Dydecka
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. m_bohdanowicz@wp.pl.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Bohdanowicz
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. tomasz.gasior@biol.ug.edu.pl.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Gąsior
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. marek.sobon@gmail.com.|Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76, Nitra, Slovakia. marek.sobon@gmail.com.
authors.forename: Marek
authors.initials: M
authors.lastname: Soboň
authors.affiliation: Institute of Oceanography, University of Gdansk, Al. Marszałka Piłsudskiego 46, 81-378, Gdynia, Poland. ocejl@ug.edu.pl.
authors.forename: Justyna
authors.initials: J
authors.lastname: Kobos
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. sylwia.bloch@biol.ug.edu.pl.
authors.forename: Sylwia
authors.initials: S
authors.lastname: Bloch
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. bozena.nejman@biol.ug.edu.pl.
authors.forename: Bożena
authors.initials: B
authors.lastname: Nejman-Faleńczyk
authors.affiliation: Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland. grzegorz.wegrzyn@biol.ug.edu.pl.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Węgrzyn
mesh_terms: D000458:Cyanobacteria / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D015723:Gene Library; D005822:Genetic Vectors; D054892:Metagenome; D056186:Metagenomics