competitive inhibition versus L-glutamate and uncompetitive inhibition versus L-alpha-aminoadipate-delta-semialdehyde and NADPH; competitive inhibition versus saccharopine and uncompetitive inhibition versus NADP+
apo form of enzyme. Protein consists of domain I, a variant of the Rossman fold and binding to NADPH, domain II with an alpha/beta structure and binding saccharopine, and domain III with all-helical fold involved in closing the active site of the enzyme once substrates are bound
gene LYS9 is organized as a chimeric spermidine synthase-saccharopine dehydrogenase gene (SPE3-LYS9) encoding functional spermidine synthase, EC 126.96.36.199, and saccharopine dehydrogenase, DNA and amino acid sequence determination and analysis, expression of wild-type enzyme in Saccharomyces cerevisiae, the chimeric gene can complement a Saccharomyces cerevisiae lys9 mutant, but not a spe3 mutant
construction of 3 Spe3-Lys9 mutants, with defects in the spe3-part, the lys9-part, or both, which are auxotrophic for lysine and spermidine, spermidine, and lysine, respectively, transcription levels and phenotype overview, the polyamine auxotrophy due to defect spe3 cannot be overcome by spermine addition, while the mutan with lys 9 defect grows slowly at 30°C with lysine addition, but dies upon lysine starvation, the mutant with defects in both gene parts is avirulent and lethal
construction of an enzyme-deficient mutant strain: disruption and inactivation of gene lys7 by double-recombination method leads to lysine auxotrophy and accumulation of piperideine-6-carboxylic acid, and with L-lysine as sole N-source and supplementation of DL-alpha-aminoadipic acid, also of pipecolic acid, transformation of the mutant strain with lys7 can restore enzyme activity
Naranjo, L.; Martin de Valmaseda, E.; Casqueiro, J.; Ullan, R.V.; Lamas-Maceiras, M.; Banuelos, O.; Martin, J.F.
Inactivation of the lys7 gene, encoding saccharopine reductase in Penicillium chrysogenum, leads to accumulation of the secondary metabolite precursors piperideine-6-carboxylic acid and pipecolic acid from alpha-aminoadipic acid