Isolation of a Variant Strain of Pleurotus eryngii and the Development of Specific DNA Markers to Identify the Variant Strain

Abstract

A degenerated strain of Pleurotus eryngii KNR2312 was isolated from a commercial farm. Random amplified polymorphic DNA analysis performed on the genomic DNA of the normal and degenerated strains of this species revealed differences in the DNA banding pattern. A unique DNA fragment (1.7 kbp), which appeared only in the degenerated strain, was isolated and sequenced. Comparing this sequence with the KNR2312 genomic sequence showed that the sequence of the degenerated strain comprised three DNA regions that originated from nine distinct scaffolds of the genomic sequence, suggesting that chromosome-level changes had occurred in the degenerated strain. Using the unique sequence, three sets of PCR primers were designed that targeted the full length, the 5' half, and the 3' half of the DNA. The primer sets P2-1 and P2-2 yielded 1.76 and 0.97 kbp PCR products, respectively, only in the case of the degenerated strain, whereas P2-3 generated a 0.8 kbp product in both the normal and the degenerated strains because its target region was intact in the normal strain as well. In the case of the P2-1 and P2-2 sets, the priming regions of the forward and reverse primers were located at distinct genomic scaffolds in the normal strain. These two primer sets specifically detected the degenerate strain of KNR2312 isolated from various mushrooms including 10 different strains of P. eryngii, four strains of P. ostreatus, and 11 other wild mushrooms.

Assessment of phylogenetic, growth, and antioxidant capacity of Pleurotus spp. in Malaysia

“…exhibited high levels of variation in terms of morphological, physiological, and production of secondary metabolites when grown in nutrient rich laboratory environments with a serial transfer of culture media (Horn & Dorner, 2002;Li et al, 1994). This phenomenon, known as strain instability or degeneration (Lee et al, 2014), might be the cause of varying antioxidant levels and also growth in P. pulmonarius.…”

The phenomenon of strain degeneration in biotechnologically relevant fungi

“…Some of these phenomena are shortly introduced in the following section in order to differentiate the term for the rest of the review. Certain basidiomycetes are reported to lose their ability to produce fruiting bodies during cultivation (Magae et al 2005;Piscitelli et al 2005;Lee et al 2014;Chen et al 2019;Zhu et al 2020;Pérez et al 2021;Zhao et al 2022). Cordyceps militaris, for example, is commercially cultivated as a pharmaceutical and food resource and frequently degenerates through subculture and storage.…”