Elizabeth Verkamp

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The small auxin up RNA (SAUR) genes were originally characterized in soybean, where they encode a set of unstable transcripts that are rapidly induced by auxin. In this report, the isolation of a SAUR gene, designated SAUR-AC1, from Arabidopsis thaliana (L.) Heynh. ecotype Columbia is described. The promoter of the SAUR-AC1 gene contains putative regulatory(More)
In green plants, archaebacteria and many eubacteria, the porphyrin ring that is common to both chlorophyll and heme is synthesized from 5-aminolevulinic acid (ALA) via an interesting pathway. This two-step process involves the unusual enzymes glutamyl-tRNA reductase and glutamate-1-semialdehyde 2,1-aminomutase. Interest in this pathway has increased since(More)
In a genetic screen designed to generate Escherichia coli strains completely devoid of the heme precursor 5-aminolevulinic acid (ALA), we isolated a class of mutants which were defective for exogenous ALA uptake. The mutations, designated alu (ALA uptake), mapped to the 80-min region of the E. coli chromosome. They were complemented by a recombinant plasmid(More)
In the first step of tetrapyrrole biosynthesis in Escherichia coli, glutamyl-tRNA reductase (GluTR, encoded by hemA) catalyzes the NADPH-dependent reduction of glutamyl-tRNA to glutamate-1-semialdehyde. Soluble homodimeric E. coli GluTR was made by co-expressing the hemA gene and the chaperone genes dnaJK and grpE. During Mg(2+)-stimulated catalysis, the(More)
From the ‡Institute of Microbiology, Technical University Braunschweig, Spielmannstrasse 7, D-38106 Braunschweig, Germany, §Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8114, Department of Biophysics, Kyoto University Sakyo-ku, Kyoto 606, Japan, **Genome Therapeutics Corp., Waltham, Massachusetts 02154,(More)
In the cyanobacterium Synechocystis sp. PCC 6803 and in the enterobacterium Escherichia coli &aminolevulinic acid (ALA) is formed from glutamyl-tRNA by the sequential action of two enzymes, glutamyl-tRNA reductase (GluTR) and glutamate 1-semialdehyde aminotransferase. E. coli has two GluTR proteins with sizes of 45 kDa (GluTR46) and 85 kDa (GluTR85) (Jahn,(More)
  • Elizabeth Verkamp, M Jahn, D Jahn, A M Kumar, D Söll
  • The Journal of biological chemistry
  • 1992
In the cyanobacterium Synechocystis sp. PCC 6803 and in the enterobacterium Escherichia coli delta-amino-levulinic acid (ALA) is formed from glutamyl-tRNA by the sequential action of two enzymes, glutamyl-tRNA reductase (GluTR) and glutamate-1-semialdehyde aminotransferase. E. coli has two GluTR proteins with sizes of 45 kDa (GluTR45) and 85 kDa (GluTR85)(More)
The Escherichia coli hemA gene, essential for the synthesis of 5-aminolevulinic acid (ALA), was isolated and sequenced. The following criteria identified the cloned gene as hemA. (i) The gene complemented a hemA mutation of E. coli. (ii) The gene was localized to approximately 26.7 min on the E. coli chromosomal linkage map, consistent with the location of(More)
The gmall auxin I I P !NA (SAUR) genes were originally characterized in soybean, where they encode a set of unstable transcripts that are rapidly induced by auxin. In this report, the isolation of a SAUR gene, designated SAUR-AC7, from Arabidopsis rhaliana (1.) Heynh. ecotype Columbia is described. l h e promoter of the SAURAC1 gene contains putative(More)
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