Stress induced alterations in the outer membrane of Escherichia coli K- 12 strain

Abstract

In the present study, gram-negative (Escherichia coli K-12) bacterial biomembrane involvement was studied in the presence of modulating factors such as EDTA, Mg ions and EDTA and Mg' ions in combination. The release of proteins and their involvement during the transport of 9-Lactams namely Ceftriaxone and Cefazolin were also studied. The broader applications of Ceftriaxone for pharmaceutical implications offer greater advantage as compared to pre-existing 3-Lactams. Due to the availability of more signal moi.:cules in the membranes there is enhanced toxicity at 5 mM EDTA concentration, and easy entrapment of antibiotics, thus enhanced sensitivity levels. A concentration of 15 mM Mg ions was found to be toxic for E.coli whereas it exhibited luxuriant growth with decreasing Mg' ion concentration under antibiotic stress. On the contrary, when 5 mM • EDTA is treated in combination wnth Mg, it attributed reduced signals available on the membrane surface therefore, reduced drug sensitivity. To identify the involvement of specific proteins and to know the site of proteins released which are directly or indirectly involved in transport of antibiotics across the biological membrane, the protein release was monitored from intact cells, as well as, membrane vesicles derived from E.colt cells and studied upto a level of molecular weight determination and measured by using a high-pressure liquid chromatography (HPLC). The study confirms the induction of certain stress signal proteins from the outer membrane, thereby rendering the bacteria more susceptible to therapy.

Keywords

• High pressure liquid chromatography
• CEF- Ceftriaxone Sodium
• CEZ-Cefazolin Sodium
• Outer Membrane Proteins- OMPs