caa a22 4500 606242686 CHVBK 20210128101320.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s12602-015-9188-4 doi (NATIONALLICENCE)springer-10.1007/s12602-015-9188-4 Protease-Sensitive Inhibitory Activity of Cell-free Supernatant of Lactobacillus crispatus 156 Synergizes with Ciprofloxacin, Moxifloxacin and Streptomycin Against Pseudomonas aeruginosa [Elektronische Daten] An In Vitro Study [Sukhraj Kaur, Preeti Sharma] Ciprofloxacin and streptomycin are frequently prescribed for the treatment of medical conditions originating due to infection by Pseudomonas aeruginosa. However, fluoroquinolone administration has been linked to the outgrowth of Clostridium difficile pathogen, especially in immunocompromised patients. Secondly, frequent administration of antibiotics may lead to development of resistance in the pathogens. Thus, there is a need to explore innovative adjunct therapies to lower the therapeutic doses of the antibiotics. Herein, we evaluated the synergism, if any, between conventional antibiotics and the cell-free supernatant (CFS) of vaginal Lactobacillus crispatus 156 against P. aeruginosa MTCC 741. L. crispatus 156 was isolated from the human vaginal tract, and its CFS had broad-spectrum antimicrobial activity against various Gram-positive and Gram-negative pathogens, including P. aeruginosa. The inhibitory substance present in the CFS completely lost its activity after treatment with proteinases and was resistant to temperatures up to 80°C and pH ranging from 2 to 6. The cumulative production of the inhibitory substance in CFS was studied, and it showed that the secretion of the inhibitory substance was initiated in middle log phase of growth and peaked in late log phase. Further, CFS synergized the activities of ciprofloxacin, moxifloxacin, and streptomycin as evaluated in terms of checkerboard titrations. It lowered the minimum inhibitory concentration (MIC) of ciprofloxacin by almost 30 times and MIC of both moxifloxacin and streptomycin by 8 times. Interestingly, pepsin treatment of CFS caused the complete abrogation of its synergistic effect with all the three antibiotics. Thus, from the study, it can be concluded that probiotic-based alternative therapeutic regimen can be designed for the treatment of P. aeruginosa infections. Springer Science+Business Media New York, 2015 Lactobacillus crispatus nationallicence Probiotic nationallicence Fluoroquinolones nationallicence Pseudomonas aeruginosa nationallicence Synergistic activity nationallicence Kaur Sukhraj Department of Microbiology, Guru Nanak Dev University, 143005, Amritsar, India aut Sharma Preeti Department of Microbiology, Guru Nanak Dev University, 143005, Amritsar, India aut Probiotics and Antimicrobial Proteins Springer US; http://www.springer-ny.com 7/2(2015-06-01), 172-180 1867-1306 7:2<172 2015 7 12602 https://doi.org/10.1007/s12602-015-9188-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s12602-015-9188-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kaur Sukhraj Department of Microbiology, Guru Nanak Dev University, 143005, Amritsar, India aut NATIONALLICENCE 700 1- Sharma Preeti Department of Microbiology, Guru Nanak Dev University, 143005, Amritsar, India aut NATIONALLICENCE 773 0- Probiotics and Antimicrobial Proteins Springer US; http://www.springer-ny.com 7/2(2015-06-01), 172-180 1867-1306 7:2<172 2015 7 12602