Abstract
Envelope fragments of E. coli K12 have been produced by freeze-fracturing "by hand" and negatively stained after thawing. The outer leaflet of the plasma membrane disintegrated upon thawing whereas the outer leaflet of the outer membrane did not. Negative staining revealed the following structural features on the outer membrane fragments: (i) "grooves" 4-6 nm wide, (ii) spherical particles 6-8 nm in diameter, (iii) "black dots" 3-8 nm in diameter. Treatment of cells with EDTA before freeze-fracturing caused dilation of grooves into holes eventually leading to fragmentation of the outer membrane. A mutant strain deficient in two outer membrane proteins fractured exclusively through the outer membrane. The outer leaflets so obtained disintegrated upon thawing similarly as observed for the outer leaflet of the plasma membrane.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
