Abstract
The phytopathogen Pseudomonas syringae subsp. savastanoi incites the production of galls on olive and oleander plants. Gall formation is dependent on bacterial production of the phytohormone indoleacetic acid (IAA). The genetic determinants for IAA synthesis are located on a plasmid (pIAA) and are organized in an operon in oleander strains of the bacterium. P. syringae subsp. savastanoi further converts IAA to an amino acid conjugate, 3-indole-acetyl-epsilon-L-lysine (IAA-lysine). The gene for IAA-lysine synthetase (iaaL) was found on the IAA plasmid by screening pIAA deletion mutants for the ability to convert IAA to IAA-lysine. The iaaL locus was then cloned in the vector pUC8 from a bank of P. syringae subsp. savastanoi EW2009 plasmid DNA to construct recombinant plasmid pLG87. The specific activity of IAA-lysine synthetase in Escherichia coli transformed with pLG87 was 47 times higher than that of the enzyme extract from P. syringae subsp. savastanoi. The direction of transcription of the iaaL gene was determined to be opposite to that of the IAA operon. The location of the iaaL gene on pIAA1 was mapped by Tn5 insertion mutagenesis to a 2.5-kilobase-pair fragment 2 kilobase pairs from the IAA operon.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference28 articles.
1. Cytokinin/auxin balance in crown gall tumors regulated by specific loci in the T-DNA;Akiyoshi D. E.;Proc. Natl. Acad. Sci. USA,1983
2. Indole-3-acetic acid (IAA) and IAA-conjugates applied to bean stem sections: IAA content and the growth response;Bialek K.;Plant Physiol.,1983
3. A complementation analysis for the restriction and modification of DNA in Escherichia coli;Boyer H. W.;J. Mol. Biol.,1969
4. Chemistry and physiology of the bound auxins. Annu;Cohen J. D.;Rev. Plant Physiol.,1982
5. Cohen J. D. and K. Bialek. 1984. The biosynthesis of indole-3-acetic acid in higher plants p. 165-181. In A. Crozier and J. R. Hillman (ed.) The biosynthesis and metabolism of plant hormones. Cambridge University Press Cambridge.
Cited by
90 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献