Interbacterial predation as a strategy for DNA acquisition in naturally competent bacteria

• Published in: Nature reviews. Microbiology Vol. 15; no. 10; pp. 621 - 629
• Main Authors: Veening, Jan-Willem, Blokesch, Melanie
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-10-2017; Nature Publishing Group
• Subjects: 631/181/2468; 631/181/2474; 631/326/1320; 631/326/325/1506; 631/326/41/1319; 631/326/41/1969/1852; 631/326/41/2180; 631/326/41/2529; 631/326/41/88; 631/326/46; Bacteria; Bacterial genetics; Bacteriocins; Biological evolution; Biological Transport; Cell interactions; Deoxyribonucleic acid; DNA; DNA Transformation Competence - genetics; DNA, Bacterial - genetics; Gene Expression Regulation, Bacterial; Gene Transfer, Horizontal - genetics; Genetic research; Genomes; Genotypes; Homology; Identification and classification; Infectious Diseases; Life Sciences; Medical Microbiology; Microbiological research; Microbiology; Mode of action; Observations; opinion-2; Parasitology; Predation; Predation (Biology); Secretion; Streptococcus infections; Streptococcus pneumoniae; Streptococcus pneumoniae - genetics; Substrates; Transformation, Bacterial - genetics; Type VI Secretion Systems - genetics; Vibrio cholerae - genetics; Virology; Waterborne diseases
• ISSN: 1740-1526; 1740-1534
• DOI: 10.1038/nrmicro.2017.66

The evolutionary function of natural competence remains controversial and several hypotheses for a function have been proposed. In this Opinion article, Veening and Blokesch propose that kin-discriminated predation that is linked to natural competence serves as a DNA acquisition strategy and therefore contributes to bacterial evolution.
Natural competence enables bacteria to take up exogenous DNA. The evolutionary function of natural competence remains controversial, as imported DNA can act as a source of substrates or can be integrated into the genome. Exogenous homologous DNA can also be used for genome repair. In this Opinion article, we propose that predation of non-related neighbouring bacteria coupled with competence regulation might function as an active strategy for DNA acquisition. Competence-dependent kin-discriminated killing has been observed in the unrelated bacteria
Vibrio cholerae
and
Streptococcus pneumoniae
. Importantly, both the regulatory networks and the mode of action of neighbour predation differ between these organisms, with
V. cholerae
using a type VI secretion system and
S. pneumoniae
secreting bacteriocins. We argue that the forced release of DNA from killed bacteria and the transfer of non-clonal genetic material have important roles in bacterial evolution.