Open AccessTransformation of an oral bacterium via chromosomal integration of free DNA in the presence of human saliva
Author(s) -
Mercer Derry K.,
Scott Karen P.,
Melville Claire M.,
Glover L.Anne,
Flint Harry J.
Publication year - 2001
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2001.tb10709.x
Subject(s) - streptococcus gordonii , plasmid , biology , transformation (genetics) , dna , genetics , circular bacterial chromosome , in vitro recombination , saliva , plasmid preparation , homology (biology) , chromosome , gene , bacteria , microbiology and biotechnology , streptococcus , molecular cloning , dna replication , biochemistry , peptide sequence , pbr322
Abstract Transformation of Streptococcus gordonii DL1 by free DNA was studied in human saliva. Competent S. gordonii could be transformed in vitro with plasmid DNA that had been taken into the human mouth. Transformation also occurred with a plasmid that cannot replicate in S. gordonii , but that has a region of chromosomal homology, by integration into the bacterial chromosome, although linearised plasmid DNA gave no transformants. Linear chromosomal DNA fragments did however transform S. gordonii /Tn 916 efficiently in saliva when regions of homology with the recipient chromosome flanked the marker gene. These findings are discussed in relation to the potential for acquisition of DNA sequences, including genetically modified DNA, by gut and oral bacteria.