AI Article Synopsis
- Under certain growth-limiting conditions, E. coli and A. vinelandii can take up poly-beta-hydroxybutyrate into their plasma membranes, impacting their genetic transformation abilities.
- The study found that higher levels of this lipid polymer in the membrane corresponded to increased competence for genetic transformation in both types of bacteria.
- Observations using freeze-fracture electron microscopy showed a transition in membrane structure as poly-beta-hydroxybutyrate was incorporated, with changes in particle patterns indicating enhanced transformability.
Article Abstract
Under growth-limiting conditions or conditions which mediate genetic transformation, Escherichia coli and Azotobacter vinelandii incorporate poly-beta-hydroxybutyrate into their plasma membranes. Genetic transformation competence of both bacteria increased in proportion to the concentration of membrane poly-beta-hydroxybutyrate. The effects of this lipid polymer on membrane structure were investigated by freeze-fracture electron microscopy. Before poly-beta-hydroxybutyrate incorporation, freeze-fracture revealed a typical mosaic of particles and pits on both concave and convex surfaces of the plasma membrane. As the cells incorporated the lipid polymer into the membrane, transformability developed and small semiregular plaques which possessed shallow particles were seen. These plaques grew in size and frequency as the membrane poly-beta-hydroxybutyrate concentrations and transformability increased.
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| http://dx.doi.org/10.1139/m87-073 | DOI Listing |
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