Antimicrobial activity of Lactobacillus salivarius and Lactobacillus fermentum against Staphylococcus aureus.
The increasing prevalence of methicillin-resistant Staphylococcus aureus has become a major public health threat. While lactobacilli were recently found useful in combating various pathogens, limited data exist on their therapeutic potential for S. aureus infections. The aim of this study was to determine whether Lactobacillus salivarius was able to produce bactericidal activities against S. aureus and to determine whether the inhibition was due to a generalized reduction in pH or due to secreted Lactobacillus product(s). We found an 8.6-log10 reduction of planktonic and a 6.3-log10 reduction of biofilm S. aureus. In contrast, the previously described anti-staphylococcal effects of L. fermentum only caused a 4.0-log10 reduction in planktonic S. aureus cells, with no effect on biofilm S. aureus cells. Killing of S. aureus was partially pH dependent, but independent of nutrient depletion. Cell-free supernatant that was pH neutralized and heat inactivated or proteinase K treated had significantly reduced killing of L. salivarius than with pH-neutralized supernatant alone. Proteomic analysis of the L. salivarius secretome identified a total of five secreted proteins including a LysM-containing peptidoglycan binding protein and a protein peptidase M23B. These proteins may represent potential novel anti-staphylococcal agents that could be effective against S. aureus biofilms.
Department of Microbial Pathogenesis, School of Dentistry, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.|Oradentics Research Institute, Seoul 06157, South Korea.
Mi-Sun
MS
Kang
Department of Microbial Pathogenesis, School of Dentistry, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.|Dental Science Research Institute, Chonnam National University, Gwangju 61186, South Korea.|Department of Dental Education, School of Dentistry, Chonnam National University, Gwangju 61186, South Korea.
Hae-Soon
HS
Lim
Department of Microbiology, School of Medicine, Chonnam National University, Gwangju 61469, South Korea.
Jong-Suk
JS
Oh
Department of Nursing, Gwangju Health University, Gwangju 62287, South Korea.
You-Jin
YJ
Lim
Institute for Biomechanics, ETH Zurich, 8093 Zurich, Switzerland.|Schön Clinic Munich Harlaching, Spine Center, Academic Teaching Hospital and Spine Research, Institute of the Paracelsus Medical University 5020 Salzburg (Austria), 81547 Munich, Germany.|Department of Health Sciences, University of Potsdam, 14469 Potsdam, Deutschland.
Karin
K
Wuertz-Kozak
Department of Microbial Pathogenesis, School of Dentistry, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.
Janette M
JM
Harro
Department of Microbial Pathogenesis, School of Dentistry, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.|Department of Microbiology and Immunology, School of Medicine, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.
Mark E
ME
Shirtliff
Department of Microbial Pathogenesis, School of Dentistry, University of Maryland-Baltimore, Baltimore, 21201 MD, USA.|Department of Infectious Diseases, University and University Hospital Zurich, 8091 Zurich, Switzerland.
Yvonne
Y
Achermann
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000898:Antibiosis; D001426:Bacterial Proteins / Q000378:metabolism / Q000494:pharmacology; D018441:Biofilms / Q000254:growth & development; D006801:Humans; D052197:Limosilactobacillus fermentum / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D000069996:Ligilactobacillus salivarius / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D050296:Microbial Viability; D009055:Mouth / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013211:Staphylococcus aureus / Q000502:physiology*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D012336:RNA, Ribosomal, 16S
Lactobacillus fermentum; Lactobacillus salivarius; LysM; Staphylococcus aureus; antibacterial activity; biofilm