Ganoderma lucidum phosphoglucomutase is required for hyphal growth, polysaccharide production, and cell wall integrity

Abstract

Phosphoglucomutase (pgm) is an important enzyme in carbohydrate metabolism that is located at the branching point between glycolysis and the Leloir pathway. pgm catalyzes the reversible conversion reaction between glucose-6-phosphate (Glc-6-P) and glucose-1-phosphate (Glc-1-P). The glpgm gene was cloned in Escherichia coli, and the recombinant pgm protein from Ganoderma lucidum was purified in this study. The activity of native pgm was also detected to demonstrate that this predicted gene was functional in G. lucidum. Interestingly, silencing the glpgm gene in the fungus reduced hyphal growth. Moreover, glpgm silencing was associated with declining extracellular polysaccharide (EPS) production (approximately 20-40% of that in the WT strain) and increasing intracellular polysaccharide (IPS) production (approximately 1.7-fold that in the WT strain). Additionally, in our research, cell wall components were also shown to differ according to the glpgmi strain. Compared with WT, chitin significantly increased by 1.5-fold; however, the content of β-1,3-glucan was observably reduced to 60-70% that of the WT. Further research showed that the cell wall component changes were associated with the transcription of related genes. These findings provide references for further study on the potential physiological function of pgm in G. lucidum.

Investigation of lignocellulolytic enzymes during different growth phases of Ganoderma lucidum strain G0119 using genomic, transcriptomic and secretomic analyses

“…lucidum were identified. Certain mitogen-activated protein kinases, transcription factor and phosphoglucomutases were found that could regulate hyphal growth, primordium formation or biosynthesis of chitin and polysaccharides through carbohydrate metabolic pathways [ 37 – 39 ]. Our results revealed more information about gene expression and protein abundance changes of the lignocellulolytic enzymes during G .…”

Cloning and characterization of phosphoglucose isomerase in Lentinula edodes

“…About 2 mL of 95% ethanol was added to the filtrate, which was incubated at 4°C overnight after stirring vigorously. The sample was removed the next day, centrifuged, and dried; finally, 1 M NaOH was used to dissolve the precipitate and suspend the insoluble components at 60°C for 1 h. The phenol‐sulfuric acid method [24] was used to measure the EPS content. The collected mycelium was dried in an oven, and hyphae were collected for IPS analysis.…”

“…Hyphae (0.01 g) were weighed, suspended in 1 M NaOH, and placed at 60°C for 1 h. Then, the sample was centrifuged, and the supernatant was used to measure the IPS content. For the phenol–sulfuric acid method, glucose was used as a standard [24].…”

Development of an Efficient Strategy to Improve Extracellular Polysaccharide Production of Ganoderma lucidum Using L-Phenylalanine as an Enhancer

“…Medium A (g/L) (Tang and Zhong, 2002) contained glucose (35), tryptone (5), yeast extract (2.5), KH 2 PO 4 ⋅H 2 O (1), MgSO 4 ⋅7H 2 O (0.5), and Vitamin B 1 (0.05), with culture conditions of 30°C at 150 rpm. Medium B (g/L) (Hu et al, 2018) contained glucose (20), tryptone (2), yeast extract 2, KH 2 PO 4 (4.6), and MgSO 4 ⋅7H 2 O (0.5), with culture conditions of 30°C at 150 rpm.…”