Isolation and characterization of bacteriocin-producing bacteria from the intestinal microbiota of elderly Irish subjects
Article first published online: 27 DEC 2012
© 2013 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 114, Issue 3, pages 886–898, March 2013
How to Cite
Lakshminarayanan, B., Guinane, C.M., O'Connor, P.M., Coakley, M., Hill, C., Stanton, C., O'Toole, P.W. and Ross, R.P. (2013), Isolation and characterization of bacteriocin-producing bacteria from the intestinal microbiota of elderly Irish subjects. Journal of Applied Microbiology, 114: 886–898. doi: 10.1111/jam.12085
- Issue published online: 18 FEB 2013
- Article first published online: 27 DEC 2012
- Accepted manuscript online: 26 NOV 2012 09:21AM EST
- Manuscript Accepted: 17 NOV 2012
- Manuscript Revised: 7 NOV 2012
- Manuscript Received: 4 SEP 2012
- Government of Ireland National Development Plan
- Health Research Board FHRI
- ELDERMET project
- Science Foundation Ireland award
- Alimentary Pharmabiotic Centre
- 16S rDNA gene amplicon sequencing;
- intestinal microbiota;
- Lactobacillus spp
To isolate and characterize bacteriocins produced by predominant species of lactic acid bacteria from faeces of elderly subjects.
Methods and Results
Screening over 70 000 colonies, from faecal samples collected from 266 subjects, using the indicator organisms Lactobacillus bulgaricus LMG 6901 and Listeria innocua DPC 3572, identified 55 antimicrobial-producing bacteria. Genomic fingerprinting following ApaI digestion revealed 15 distinct strains. The antimicrobial activities associated with 13 of the 15 strains were sensitive to protease treatment. The predominant antimicrobial-producing species were identified as Lactobacillus salivarius, Lactobacillus gasseri, Lactobacillus acidophilus, Lactobacillus crispatus and Enterococcus spp. A number of previously characterized bacteriocins, including ABP-118 and salivaricin B (from Lact. salivarius), enterocin B (Enterococcus faecium), lactacin B (Lact. acidophilus), gassericin T and a variant of gassericin A (Lact. gasseri), were identified. Interestingly, two antimicrobial-producing species, not generally associated with intestinally derived microorganisms were also isolated: Lactococcus lactis producing nisin Z and Streptococcus mutans producing mutacin II.
These data suggest that bacteriocin production by intestinal isolates against our chosen targets under the screening conditions used was not frequent (0·08%).
Significance and Impact of the Study
The results presented are important due to growing evidence indicating bacteriocin production as a potential probiotic trait by virtue of strain dominance and/or pathogen inhibition in the mammalian intestine.