Cell wall and plasma membrane architecture of Butyrivibrio spp.

Abstract

The cell wall and plasma membrane of four strains of Butyrivibrio (anaerobic rumen bacteria) have been studied by freeze-etching and thin sectioning. Some strains have a wall of gram-positive ultrastructure, which is vulnerable to lysozyme, while others have a wall which resembles the outer envelope of a gram-negative bacterium and is less susceptible to lysozyme. The plasma membrane of all strains is rather rigid, and its lipids have a very high phase-transition temperature.