PERMEABILITY OF THE ESCHERICHIA-COLI OUTER-MEMBRANE TO ETHIDIUM IONS AND PERIPLASMIC ALKALINE-PHOSPHATASE DURING ENHANCED SYNTHESIS OF THE ALKALINE-PHOSPHATASE
Ni. Mikhaleva et al., PERMEABILITY OF THE ESCHERICHIA-COLI OUTER-MEMBRANE TO ETHIDIUM IONS AND PERIPLASMIC ALKALINE-PHOSPHATASE DURING ENHANCED SYNTHESIS OF THE ALKALINE-PHOSPHATASE, Biochemistry, 60(7), 1995, pp. 881-887
The outer membrane of various Escherichia coli strains overproducing p
eriplasmic alkaline phosphatase was found to be permeable not only to
the enzyme, but also to ethidium ions, which normally do not penetrate
into gram-negative bacteria. In the absence of the outer membrane lip
oprotein, the permeability of the membrane to these compounds and its
sensitivity to membranotropic agents increase, indicating a role of th
e lipoprotein in the barrier properties of the outer membrane. A negat
ive correlation was revealed between the contents of lipoprotein and l
ipopolysaccharide in the outer membrane and between their content and
alkaline phosphatase secretion into the medium. It is suggested that t
he increased permeability of the Escherichia coli outer membrane durin
g overproduction of the secreted protein is due to impaired biogenesis
of membrane components.