Table of Contents Author Guidelines Submit a Manuscript
BioMed Research International
Volume 2015, Article ID 651464, 7 pages
Research Article

Studies on Molecular Characterizations of the Outer Membrane Proteins, Lipids Profile, and Exopolysaccharides of Antibiotic Resistant Strain Pseudomonas aeruginosa

1Food Science and Nutrition Department, College of Food and Agriculture Sciences, King Saud University, Saudi Arabia
2Food Science and Nutrition, Faculty of Home Economics, Helwan University, Egypt
3Department of Botany (Microbiology), Faculty of Science, Zagazig University, Zagazig, Egypt

Received 29 September 2014; Accepted 24 November 2014

Academic Editor: Anjali Joshi

Copyright © 2015 Hany M. Yehia et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Susceptibility of the tested Pseudomonas aeruginosa strain to two different antibiotics, tetracycline (TE) and ciprofloxacin (CIP), was carried out using liquid dilution method. Minimum inhibitory concentrations of TE and CIP were 9.0 and 6.0 mg/100 mL, respectively. Some metabolic changes due to both, the mode of action of TE and CIP on P. aeruginosa and its resistance to high concentrations of antibiotics (sub-MIC) were detected. The total cellular protein contents decreased after antibiotic treatment, while outer membrane protein (OMP) contents were approximately constant for both treated and untreated cells. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the OMPs for untreated and TE and CIP treated cells indicated that the molecular changes were achieved as; lost in, induction and stability of some protein bands as a result of antibiotics treatment. Five bands (with mol. wt. 71.75, 54.8, 31.72, 28.63, and 20.33 KDa) were stable in both treated and untreated tested strains, while two bands (with mol. wt. 194.8 and 118.3 KDa) were induced and the lost of only one band (with mol. wt. 142.5 KDa) after antibiotics treatment. On the other hand, total lipids and phospholipids increased in antibiotic treated cells, while neutral lipids decreased. Also, there was observable stability in the number of fatty acids in untreated and treated cells (11 fatty acids). The unsaturation index was decreased to 56% and 17.6% in both TE and CIP treatments, respectively. The produced amount of EPSs in untreated cultures of P. aeruginosa was relatively higher than in treated cultures with sub-MICs of TE and CIP antibiotics. It was also observed that the amounts of exopolysaccharides (EPSs) increased by increasing the incubation period up to five days of incubation in case of untreated and antibiotic treated cultures.