title: Complementation of mutations in Escherichia coli and Bordetella pertussis by B. pertussis DNA cloned in a broad-host-range cosmid vector.
abstract: A gene library of Bordetella pertussis DNA was constructed in Escherichia coli using the broad-host-range cosmid vector pLAFR1. The average insert size was 24.9 kb. From 500 members of the gene library, clones were identified which complemented trpE, glnA and Thr- mutations in E. coli but none which complemented trpD, trpC, trpB, trpA, proA or Leu- mutations. Four clones were identified which complemented trpE in E. coli. Anthranilate synthase activity was detected in a trpE strain only when it harboured a plasmid from one of these clones; activity was repressed when tryptophan was included in the growth medium. Two clones were identified which complemented glnA of E. coli. A recombinant plasmid from one of these clones also restored some of the nitrogen acquisition functions of glnG and glnL in E. coli. Expression of several B. pertussis virulence-associated products (haemolysin, heat-labile toxin, adenylate cyclase, filamentous haemagglutinin, and the cell-envelope polypeptide of Mr 30,000) was not detected in 500 independent clones. However, by transferring the recombinant plasmids to a mutant of B. pertussis deficient in haemolysin and adenylate cyclase, a plasmid was identified which restored both these activities.
mesh_terms: D000878:Anthranilate Synthase / Q000378:metabolism; D001886:Bordetella pertussis / Q000201:enzymology / Q000235:genetics*; D003001:Cloning, Molecular; D003360:Cosmids; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism; D009154:Mutation
chemical_list: D004269:DNA, Bacterial; D000878:Anthranilate Synthase; D005974:Glutamate-Ammonia Ligase