Cell surface interactions between Bdellovibrio and its prey

Date

1984-08

Journal Title

Journal ISSN

Volume Title

Publisher

Texas Tech University

Abstract

Bdallovibrios are predatory gram-nagativa bacteria which have been suspected of stealing proteins from the outer membranes of their prey. I studied the outer membrane proteins of Bdellovibrio and its prey to show this phenomenon. Both the obligately parasitic strain Bdellovibrio bacteriovorus 109D and tha facultatively parasitic strain Bdellovibrio stolpii were used in these studies. Bedllovibrios ware cultivated on several types or strains of prey for outer membrane protein analysis using SDS-polyacrylamide gel electrophoresis.

I found that Bdellovibrio acquires the OmpF major outer membrane protein of its Escherichia coli prey. Growth of bdellovibrios on mutant prey defective in outer membrane protein expression showed that in the absence of tha OmpF protein, the OmpC protein was acquired, but protein 2 was not. These results suggest that there is a specific Bdellovibrio preference for the OmpF protein, and furthermore it shows that our results did not arise from preparatory contamination.

It was further determined through kinetic measurement of the disappearance of the OmpF and OmpC proteins from the bdelloplast surface, that Bdellovibrio does have a preference for the prey OmpF protein. Additionally, colicin studies and antibiotic killing kinetic experiments indicated that the prey-derived OmpF protein retained its porin function in the Bdellovibrio outer membrane.

In summary, Bdellovibrio acquisition of prey outer membranes is unique, and the concommitant transfer of biological activity from prey outer membrane to Bdellovibrio outer membrane is a novel occurrence.

Description

Keywords

Bdellovibrio bacteriovorus, Escherichia coli, Enterobacteriaceae, Gram-negative bacteria, Membrane proteins

Citation