Isolation and purification of major outer membrane proteins (OMP) from the cell wall envelope of Brucella abortus S-99 were achieved by sonication, solubilization and membrane fractionation in the presence of non-ionic detergent (Tx-100) and lysozyme treatments, followed by ultracentrifugation. The crude OMP was treated with trypsin to free the preparation from any other protein contaminan...

Gram-negative bacteria export a large variety of antimicrobial compounds by forming two-membrane spanning tripartite multidrug efflux systems composed an inner membrane transporter, outer channel and periplasmic adaptor protein. Here we present the co-expression, purification first electron microscopy insights Escherichia coli EmrAB–TolC Major Facilitator Superfamily (MSF) system as whole compl...

The outer membrane fraction from Rhodopseudomonas sphaeroides was isolated by isopycnic density centrifugation. The purity of this fraction was assayed by several methods. When the outer membrane fraction obtained after French press lysis of cells was compared with the outer membrane fragments released during spheroplast formation, the polypeptide profiles were identical. Detergent solubilizati...

The major outer membrane protein patterns of 45 Escherichia coli strains of human origin were compared with that of E. coli K12 by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Preparations of the former strains contained between two and five major bands in the molecular weight range between 30 000 and 42 000. The patterns were very heterogeneous with respect to the numbers and el...

introduction: legionnair's disease bacterium is a gram negative, facultative intracellular bacilli which parasitize human alveolar macropages as well as some species of free living amobae. this study was achieved in order to compare the cell wall composition in intracellular bacteria. whole cell and outer membrane proteins and the bacterial lipopolysacharide (lps) were analyzec on sds page syst...