Open AccessInhibition of methicillin‐resistant Staphylococcus aureus by an in vitro continuous‐flow culture containing human stool microflora
Author(s) -
Pultz Nicole J.,
Hoyen Claudia K.,
Donskey Curtis J.
Publication year - 2004
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 - 10.1016/j.femsle.2004.10.021
Subject(s) - obligate anaerobe , microbiology and biotechnology , staphylococcus aureus , anaerobic exercise , biology , in vitro , obligate , continuous flow , anaerobic bacteria , colonization , bacteria , biochemistry , physiology , ecology , genetics , physics , mechanics
We used an in vitro continuous‐flow culture model of human stool microflora to examine the ability of human stool microflora to inhibit growth of two methicillin‐resistant S. aureus (MRSA) strains. Continuous‐flow cultures consistently eliminated MRSA inocula of 10 6 cfu/mL within 4 days, and addition of continuous‐flow culture resulted in elimination of a pre‐established MRSA culture (∼10 8 cfu/mL) within 6–8 days. Anaerobic or “aerobic” (i.e., continuous bubbling of room air to eliminate obligate anaerobes) cultures eliminated MRSA at similar rates. The MRSA strains were unable to replicate under anaerobic conditions in sterile filtrates produced from the continuous‐flow culture, but rapid growth occurred when glucose was added. These data demonstrate that indigenous stool microflora efficiently eliminate MRSA colonization and obligate anaerobes are not essential for inhibition. Our findings also suggest that inhibition of MRSA in continuous‐flow cultures is due to depletion of nutrients rather than production of inhibitory conditions.