Overexpression of the saccharopine dehydrogenase gene improves lysine biosynthesis in Flammulina velutipes

2019 ◽  
Vol 59 (9) ◽  
pp. 890-900 ◽  
Author(s):  
Jianyu Liu ◽  
Qiaozhen Li ◽  
Peiyu Jiang ◽  
Zhen Xu ◽  
Dan Zhang ◽  
...  
Keyword(s):  
Lysine Biosynthesis ◽  
Flammulina Velutipes ◽  
Saccharopine Dehydrogenase ◽  
Dehydrogenase Gene

scholarly journals Novel Chimeric Spermidine Synthase-Saccharopine Dehydrogenase Gene (SPE3-LYS9) in the Human Pathogen Cryptococcus neoformans

2004 ◽  
Vol 3 (3) ◽  
pp. 752-763 ◽  
Author(s):  
Joanne M. Kingsbury ◽  
Zhonghui Yang ◽  
Tonya M. Ganous ◽  
Gary M. Cox ◽  
John H. McCusker
Keyword(s):  
Cryptococcus Neoformans ◽  
Lysine Biosynthesis ◽  
Temperature Sensitive ◽  
Mrna Levels ◽  
Spermidine Synthase ◽  
Gene Encoding ◽  
Saccharopine Dehydrogenase ◽  
Dehydrogenase Gene

ABSTRACT The Cryptococcus neoformans LYS9 gene (encoding saccharopine dehydrogenase) was cloned and found to be part of an evolutionarily conserved chimera with SPE3 (encoding spermidine synthase). spe3-lys9, spe3-LYS9, and SPE3-lys9 mutants were constructed, and these were auxotrophic for lysine and spermidine, spermidine, and lysine, respectively. Thus, SPE3-LYS9 encodes functional spermidine synthase and saccharopine dehydrogenase gene products. In contrast to Saccharomyces cerevisiae spe3 mutants, the polyamine auxotrophy of C. neoformans spe3-LYS9 mutants was not satisfied by spermine. In vitro phenotypes of spe3-LYS9 mutants included reduced capsule and melanin production and growth rate, while SPE3-lys9 mutants grew slowly at 30°C, were temperature sensitive in rich medium, and died upon lysine starvation. Consistent with the importance of saccharopine dehydrogenase and spermidine synthase in vitro, spe3-lys9 mutants were avirulent and unable to survive in vivo and both functions individually contributed to virulence. SPE3-LYS9 mRNA levels showed little evidence of being influenced by exogenous spermidine or lysine or starvation for spermidine or lysine; thus, any regulation is likely to be posttranscriptional. Expression in S. cerevisiae of the full-length C. neoformans SPE3-LYS9 cDNA complemented a lys9 mutant but not a spe3 mutant. However, expression in S. cerevisiae of a truncated gene product, consisting of only C. neoformans SPE3, complemented a spe3 mutant, suggesting possible modes of regulation. Therefore, we identified and describe a novel chimeric SPE3-LYS9 gene, which may link spermidine and lysine biosynthesis in C. neoformans.

scholarly journals A T-DNA Insertion Knockout of the Bifunctional Lysine-Ketoglutarate Reductase/Saccharopine Dehydrogenase Gene Elevates Lysine Levels in Arabidopsis Seeds

2001 ◽  
Vol 126 (4) ◽  
pp. 1539-1545 ◽  
Author(s):  
Xiaohong Zhu ◽  
Guiliang Tang ◽  
Fabienne Granier ◽  
David Bouchez ◽  
Gad Galili
Keyword(s):  
Saccharopine Dehydrogenase ◽  
Dehydrogenase Gene ◽  
Dna Insertion

scholarly journals Molecular Evolution of Lysine Biosynthesis in Agaricomycetes

2021 ◽  
Vol 8 (1) ◽  
pp. 37
Author(s):  
Zili Song ◽  
Maoqiang He ◽  
Ruilin Zhao ◽  
Landa Qi ◽  
Guocan Chen ◽  
...  
Keyword(s):  
Molecular Evolution ◽  
Evolutionary Relationship ◽  
Deep Understanding ◽  
Evolutionary Conservation ◽  
Fungal Species ◽  
Lysine Biosynthesis ◽  
Tertiary Structures ◽  
Saccharopine Dehydrogenase ◽  
Homocitrate Synthase ◽  
Substrate Binding Sites

As an indispensable essential amino acid in the human body, lysine is extremely rich in edible mushrooms. The α-aminoadipic acid (AAA) pathway is regarded as the biosynthetic pathway of lysine in higher fungal species in Agaricomycetes. However, there is no deep understanding about the molecular evolutionary relationship between lysine biosynthesis and species in Agaricomycetes. Herein, we analyzed the molecular evolution of lysine biosynthesis in Agaricomycetes. The phylogenetic relationships of 93 species in 34 families and nine orders in Agaricomycetes were constructed with six sequences of LSU, SSU, ITS (5.8 S), RPB1, RPB2, and EF1-α datasets, and then the phylogeny of enzymes involved in the AAA pathway were analyzed, especially homocitrate synthase (HCS), α-aminoadipate reductase (AAR), and saccharopine dehydrogenase (SDH). We found that the evolution of the AAA pathway of lysine biosynthesis is consistent with the evolution of species at the order level in Agaricomycetes. The conservation of primary, secondary, predicted tertiary structures, and substrate-binding sites of the enzymes of HCS, AAR, and SDH further exhibited the evolutionary conservation of lysine biosynthesis in Agaricomycetes. Our results provide a better understanding of the evolutionary conservation of the AAA pathway of lysine biosynthesis in Agaricomycetes.

scholarly journals Lysine catabolism: flow, metabolic role and regulation

2003 ◽  
Vol 15 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Ricardo Francisco Fornazier ◽  
Ricardo Antunes Azevedo ◽  
Renato Rodrigues Ferreira ◽  
Vanderlei Aparecido Varisi
Keyword(s):  
Environmental Changes ◽  
Lysine Biosynthesis ◽  
Direct Result ◽  
Physiological Processes ◽  
Saccharopine Dehydrogenase ◽  
Metabolic Role ◽  
Lysine Concentration ◽  
Lysine Degradation ◽  
Acid Pathway ◽  
Lysine Catabolism

Lysine is an essential amino acid, synthesized in plants in the aspartic acid pathway. The lysine catabolism is performed by the action of two consecutive enzymes, lysine 2-oxoglutarate reductase (LOR) and saccharopine dehydrogenase (SDH). The steady state of lysine is controlled by both, synthesis and catabolism rates, with the final soluble lysine concentration in cereal seeds a direct result of these processes. In the last 40 years, the enzymes involved in lysine biosynthesis have been purified and characterized from some plant species such as carrot, maize, barley, rice, and coix. Recent reports have revealed that lysine degradation might be related to various physiological processes, for instance growth, development and response to environmental changes and stress. The understanding of the regulatory aspects of the lysine biosynthetic and catabolic pathways and manipulation of related enzymes is important for the production of high-lysine plants.

α-Aminoadipate pool concentration and penicillin biosynthesis in strains of Penicillium chrysogenum

1986 ◽  
Vol 32 (6) ◽  
pp. 473-480 ◽  
Author(s):  
W. M. Jaklitsch ◽  
W. Hampel ◽  
M. Röhr ◽  
C. P. Kubicek ◽  
G. Gamerith
Keyword(s):  
Amino Acid ◽  
Penicillium Chrysogenum ◽  
Intracellular Concentration ◽  
Lysine Biosynthesis ◽  
Penicillin Biosynthesis ◽  
Penicillin Production ◽  
Saccharopine Dehydrogenase ◽  
Two Factors ◽  
Homocitrate Synthase ◽  
Rate Limiting

Intracellular amino acid pools in four Penicillium chrysogenum strains, which differed in their ability to produce penicillin, were determined under conditions supporting growth without penicillin production and under conditions supporting penicillin production. A significant correlation between the rate of pencillin production and the intracellular concentration of α-aminoadipate was observed, which was not shown with any other amino acid in the pool. In replacement cultivation, penicillin production was stimulated by α-aminoadipate, but not by valine or cysteine. Exogenously added α-aminoadipate (2 or 3 mM) maximally stimulated penicillin synthesis in two strains of different productivity. Under these conditions intracellular concentrations of α-aminoadipate were comparable in the two strains in spite of the higher rate of penicillin production in the more productive strain. Results suggest that the lower penicillin titre of strain Q 176 is due to at least two factors: (i) the intracellular concentration of α-aminoadipate is insufficient to allow saturation of any enzyme which is rate limiting in the conversion of α-aminoadipate to penicillin and (ii) the level of an enzyme, which is rate limiting in the conversion of α-aminoadipate to penicillin, is lower in Q 176 (relative to strain D6/1014/A). Results suggest that the intracellular concentration of α-aminoadipate in strain D6/1014/A is sufficiently high to allow saturation of the rate-limiting penicillin biosynthetic enzyme in that strain. The basis of further correlation of intracellular α-aminoadipate concentration and penicillin titre among strains D6/1014/A, P2, and 389/3, the three highest penicillin producers studied here, remains to be established. Preliminary studies which attempted to explain the differences in intracellular α-aminoadipate concentrations in strains Q 176, D6/1014/A, and P2 in terms of differences in activities or kinetics of two enzymes of lysine biosynthesis (homocitrate synthase and saccharopine dehydrogenase) did not reveal differences in those enzymes among the three strains.

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