Increased production of ganoderic acids by overexpression of homologous farnesyl diphosphate synthase and kinetic modeling of ganoderic acid production in Ganoderma lucidum

Abstract

Background Ganoderic acids (GAs), derived from the medicinal mushroom Ganoderma lucidum , possess anticancer and other important pharmacological activities. To improve production of GAs, a homologous farnesyl diphosphate synthase (FPS) gene was overexpressed in G. lucidum . Moreover, the influence of FPS gene overexpression on GA production was investigated by developing the corresponding mathematical models. Results The maximum levels of total GAs and individual GAs (GA-T, GA-S, and GA-Me) in the transgenic strain were 2.76 mg/100 mg dry weight (DW), 41 ± 2, 21 ± 5, and 28 ± 1 μg/100 mg DW, respectively, which were increased by 2.28-, 2.27-, 2.62-, and 2.80-folds compared with those in the control. Transcription levels of squalene synthase (SQS) and lanosterol synthase (LS) genes during GA biosynthesis were upregulated by 2.28- and 1.73-folds, respectively, in the transgenic G. lucidum . In addition, the developed unstructured models had a satisfactory fit for the process of GA production in submerged cultures of G. lucidum . Analysis of the kinetic process showed that FPS gene overexpression had a stronger positive impact on GA production compared with its influence on cell growth. Also, FPS gene overexpression led to a higher non-growth-associated-constant β (1.151) over the growth-associated-constant α (0.026) in the developed models. Conclusions FPS gene overexpression is an effective strategy to improve the production of GAs in G. lucidum . The developed mathematical models are useful for developing a better GA production process in future large-scale bioreactors. Electronic supplementary material The online version of this article (10.1186/s12934-019-1164-3) contains supplementary material, which is available to authorized users.

Efficient expression of heterologous genes by the introduction of the endogenous glyceraldehyde-3-phosphate dehydrogenase gene intron 1 in Ganoderma lucidum

“…Approximately 1 mg total RNA was used as template, and reverse transcription was performed using the PrimeScript™ RT reagent Kit (Takara, China) following the manufacturer’s instructions. The transcription levels of opbar and opgus were determined by qRT-PCR as previously described [ 6 , 16 ]. The 18S-rRNA transcript was used as internal control to normalize relative transcription levels.…”

Dual sgRNA‐directed gene deletion in basidiomycete Ganoderma lucidum using the CRISPR/Cas9 system

“…Genetic transformation systems, including Agrobacterium tumefacien ‐mediated and polyethylene glycol (PEG)‐mediated transformations, have been developed in G. lucidum (Shi et al , ; Xu et al , ; Xu and Zhong, ) and have been successfully used to enhance the production of bioactive compounds, such as ganoderic acids and polysaccharides (Zhou et al , ; Li et al , ; Zhang et al , , ; Fei et al , ; Xu et al , ). Gene silencing systems have also been used for the partial suppression of genes of interest in G. lucidum (Mu et al , ; Liu et al , ; Zhu et al , ).…”

Transcriptome dynamics and metabolite analysis revealed the candidate genes and regulatory mechanism of ganoderic acid biosynthesis during liquid superficial‐static culture of Ganoderma lucidum

“…FPS was also encoded by two genes, and the FPKM value of FPS‐2 was higher than that of FPS‐1 . In G. lucidum , FPS gene, actually it is FPS‐2 gene, overexpression was an effective strategy to improve the production of GAs (Fei et al ., 2019). Although FPS‐1 gene had a low expression level, it was upregulated from day 4 to day 6 in LSSC which meant it need to be further study for the role in triterpenoid biosynthetic pathway.…”

“…The genes involved in the lanostane skeleton biosynthesis pathway, such as encoding AACT, hydroxymethylglutaryl‐CoA (HMGS), 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase (HMGR), mevalonate pyrophosphate decarboxylase (MVD), isopentenyl diphosphate isomerase (IDI), FPS, squalene synthase (SQS) and lanosterol synthase (LS), were cloned from G. lucidum (Zhao et al ., 2007; Ding et al ., 2008; Shang et al ., 2008, 2010; Shi et al ., 2012; Fang et al ., 2013; Ren et al ., 2013; Wu et al ., 2013). Overexpression of genes encoding HMGR, FPS, SQS, squalene epoxidase (SE) and LS, which are considered as the major regulatory point, could enhance GA production (Xu et al ., 2012; Zhou et al ., 2014; Zhang et al ., 2017a, b; Fei et al ., 2019). Nevertheless, details regarding the later steps to biosynthesize the individual GAs, including the cyclization, oxidation and reduction reactions, are unclear.…”