caa a22 4500 477099947 CHVBK 20180405111538.0 cr unu---uuuuu 170330e19960901xx s 000 0 eng 10.1007/BF00196650 doi (NATIONALLICENCE)springer-10.1007/BF00196650 Enzymatic properties of chorismate synthase isozymes of tomato ( Lycopersicon esculentum Mill.) [Elektronische Daten] [Martin Braun, John Henstrand, Jörn Görlach, Nikolaus Amrhein, Jürg Schmid] Three plastidic chorismate synthase isozymes (CS1, CS2 and CS2Δ) of tomato were identified by isolation of the corresponding cDNAs. These three cDNAs are derived from only two genes (LeCS1 and LeCS2). This additional complexity results from differential splicing of the primary transcript of one of the genes (LeCS2) giving rise to two different transcripts (CS2 and CS2Δ transcripts). All three isozymes were individually expressed in Escherichia coli both as precursor proteins with N-terminal transit peptides and as mature proteins. Only the mature but not the precursor isozymes CS1 and CS2 were enzymatically active. The enzyme CS2Δ was unstable in E. coli. Both CS1 and CS2 were purified to near homogeneity and their enzymatic properties were analyzed. They differ substantially in their K m values for the substrate 5-enol-pyruvylshikimate 3-phosphate (11 and 80 μM for the mature forms of CS1 and CS2, respectively). The two isozymes appear to be active only as oligomers, and the potential physiological implications of this result are discussed. Springer-Verlag, 1996 Chorismate synthase nationallicence Isozymes nationallicence Lycopersicon nationallicence Shikimate pathway nationallicence CS : chorismate synthase nationallicence CS1, CS2, CS2Δ : tomato chorismate synthase isozymes nationallicence DMS : [dimethylsuberimidate nationallicence EPSP : 5-enolpyruvylshikimate 3-phosphate nationallicence IPTG : isopropylβ-d-thiogalactopyranoside nationallicence LeCS1 , LeCS2 : tomato chorismate synthase genes nationallicence Braun Martin Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut Henstrand John Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut Görlach Jörn Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut Amrhein Nikolaus Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut Schmid Jürg Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut Planta Springer-Verlag 200/1(1996-09-01), 64-70 0032-0935 200:1<64 1996 200 425 https://doi.org/10.1007/BF00196650 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00196650 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Braun Martin Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut NATIONALLICENCE 700 1- Henstrand John Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut NATIONALLICENCE 700 1- Görlach Jörn Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut NATIONALLICENCE 700 1- Amrhein Nikolaus Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut NATIONALLICENCE 700 1- Schmid Jürg Institute of Plant Sciences, Swiss Federal Institute of Technology, Universitätstrasse 2, CH-8092, Zürich, Switzerland aut NATIONALLICENCE 773 0- Planta Springer-Verlag 200/1(1996-09-01), 64-70 0032-0935 200:1<64 1996 200 425 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer