CONSTRUCTION AND INITIAL ANALYSIS OF A REPRESENTATIVE LAMBDA-ZAPII EXPRESSION LIBRARY OF THE INTRACELLULAR RICKETTSIA COWDRIA-RUMINANTIUM -CLONING OF MAP1 AND 3 OTHER COWDRIA GENES

The causative agent of heartwater, the rickettsia Cowdria ruminantium, is very poorly understood at the molecular level owing to a profound lack of suitable tools. We have developed an immunoaffinity chromatogr aphic method to purify C. ruminantium from host cell components and th e purified rickettsial cells have been used to prepare substantially p ure Cowdria DNA. This DNA has been used to construct what we believe t o be the first fully representative C. ruminantium expression library. A clone containing the complete Cowdria map1 gene has been isolated a nd sequenced. This gene has been expressed in E. coli cells from the n ative Cowdria promoter, suggesting that the mechanisms for gene transc ription and translation are similar between these two organisms. Parts of three other Cowdria genes have also been isolated and sequenced. ( C) 1997 Elsevier Science B.V.