title: Significant antibacterial activity and synergistic effects of camel lactoferrin with antibiotics against methicillin-resistant Staphylococcus aureus (MRSA).
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) causes major healthcare problems in many countries, as it is present as several hospital- and community-associated strains. Hospital-associated MRSA is one of the most prevalent nosocomial pathogens throughout the world and infections caused by community-acquired MRSA are rising. This emphasizes the need for new and efficient anti-MRSA agents. We evaluated the antibacterial effects of camel lactoferrin (cLf) and human lactoferrin (hLf) alone and in combination with several antibiotics against MRSA. Antimicrobials were tested against MRSA and an S. aureus control strain by the agar disc diffusion method. The minimum inhibitory concentration (MIC) was determined for antimicrobials by the broth microdilution method. Synergy between cLf or hLf and antibiotics was examined by checkerboard and time-kill assays. The agar disc diffusion assay showed that MRSA growth was inhibited by cLf at 0.25-3 mg/ml and hLf at 1-3 mg/ml. cLf demonstrated 3 times higher inhibitory activity against MRSA than hLf in terms of MIC values (250 vs. 750 μg/ml, respectively). Biotinylated cLf was recognized by two membrane proteins of MRSA, 66-67 KDa. Combinations of cLf or hLf and oxacillin or vancomycin at sub-MIC levels enhanced in vitro antibacterial activity against MRSA compared with each agent alone.
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Therapeutic and Protective Proteins Laboratory, Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, New Borg EL-Arab, 21934 Alexandria, Egypt. Electronic address: redwan1961@yahoo.com.
authors.forename: Elrashdy M
authors.initials: EM
authors.lastname: Redwan
authors.affiliation: Therapeutic and Protective Proteins Laboratory, Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, New Borg EL-Arab, 21934 Alexandria, Egypt.
authors.forename: Nawal Abd
authors.initials: NA
authors.lastname: El-Baky
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Al-Hejin
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Mohammed N
authors.initials: MN
authors.lastname: Baeshen
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Hussein A
authors.initials: HA
authors.lastname: Almehdar
authors.affiliation: Microbiology Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.
authors.forename: Abdulrahman
authors.initials: A
authors.lastname: Elsaway
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Agricultural Microbiology Department, National Research Centre, Cairo, Egypt.
authors.forename: Abu-Bakr M
authors.initials: AB
authors.lastname: Gomaa
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Saad Berki
authors.initials: SB
authors.lastname: Al-Masaudi
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Fahad A
authors.initials: FA
authors.lastname: Al-Fassi
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Isam Eldin
authors.initials: IE
authors.lastname: AbuZeid
authors.affiliation: Biological Sciences Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Uversky
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002162:Camelus; D004357:Drug Synergism; D006801:Humans; D007781:Lactoferrin / Q000494:pharmacology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests
chemical_list: D000890:Anti-Infective Agents; D007781:Lactoferrin
keywords: Antibiotics; Lactoferrin; MRSA; Synergistic action