Editor: Marco Soria
A novel class of small repetitive DNA sequences in Enterococcus faecalis
Article first published online: 10 APR 2007
FEMS Microbiology Letters
Volume 271, Issue 2, pages 193–201, June 2007
How to Cite
Venditti, R., De Gregorio, E., Silvestro, G., Bertocco, T., Salza, M. F., Zarrilli, R. and Di Nocera, P. P. (2007), A novel class of small repetitive DNA sequences in Enterococcus faecalis. FEMS Microbiology Letters, 271: 193–201. doi: 10.1111/j.1574-6968.2007.00717.x
- Issue published online: 10 APR 2007
- Article first published online: 10 APR 2007
- Received 26 January 2007; revised 6 March 2007; accepted 6 March 2007.First published online 10 April 2007.
- stem-loop structures;
- palindromic DNA;
- miniature insertion sequence;
- genome analysis;
- microbiological diagnostic
The structural organization of Enterococcus faecalisrepeats (EFAR) is described, palindromic DNA sequences identified in the genome of the Enterococcus faecalis V583 strain by in silico analyses. EFAR are a novel type of miniature insertion sequences, which vary in size from 42 to 650 bp. Length heterogeneity results from the variable assembly of 16 different sequence types. Most elements measure 170 bp, and can fold into peculiar L-shaped structures resulting from the folding of two independent stem-loop structures (SLSs). Homologous chromosomal regions lacking or containing EFAR sequences were identified by PCR among 20 E. faecalis clinical isolates of different genotypes. Sequencing of a representative set of ‘empty’ sites revealed that 24–37 bp-long sequences, unrelated to each other but all able to fold into SLSs, functioned as targets for the integration of EFAR. In the process, most of the SLS had been deleted, but part of the targeted stems had been retained at EFAR termini.