ldentif ication of three differentially expressed hydrophobins in Pleurotus ostreatus (oyster mushroom)

Abstract

Three proteins with characteristic features of class I hydrophobins, designated POH1, POH2 and POH3, were isolated from the basidiomycete PIeurotus ostreatus. Based on N-terminal sequence analyses, their cDNAs were isolated using RT-PCR; the cDNAs and corresponding genes were sequenced and their regulation studied. POHI is expressed in the fruiting bodies but not in vegetative mycelium. The regulation of fWf2 and poH3 is tightly correlated. Both genes are switched off in the fruiting bodies but abundantly expressed in the vegetative mycelium of both monokaryon and dikaryon. POH2 and POH3 were isolated from the culture medium and from aerial hyphae. Co-purified POH2 and POH3 assembled in witro into a protein membrane with a typical rodlet pattern as found previously with other hydrophobins. Similar structures were detected on the surface of aerial hyphae.

Differentially Regulated, Vegetative-Mycelium-Specific Hydrophobins of the Edible Basidiomycete Pleurotus ostreatus

“…ostreatus (4). POH2 and SC3 hydrophobins contain a threonine-rich region at the N terminus of the mature protein that can be involved in O glycosylation (4,14). No threonine-or serine-rich regions, however, are present in Vmh3, suggesting that the glycosylation site in this case should be different.…”

“…florida (this paper) and POH2 and POH3 from var. ostreatus (4). In this work, we investigated (Table 3) suggests that they diverged a long time ago, although the differences between similarity scores at nucleotide and amino acid levels indicate that the these proteins' primary structures should be subjected to a considerable selective pressure that limits sequence drift.…”

“…ostreatus (4). In order to determine their map positions, probes corresponding to on May 9, 2018 by guest http://aem.asm.org/ them were used for mapping as described above.…”

“…Commercial varieties florida and ostreatus differ in size, color, and temperature tolerance. Both varieties have been used in previous studies about the hydrophobins present in this fungus (4,35). In this paper, we describe the purification of three new hydrophobins produced in the vegetative mycelium of P. ostreatus and analyze their genes and production in submerged culture under different nutritional conditions.…”

Genetic Linkage Map of the Edible Basidiomycete Pleurotus ostreatus

“…Besides its importance for food production, P. ostreatus is interesting for applications such as paper pulp bleaching, cosmetics, and the pharmaceutical industry. These different applications have fueled research on specific aspects of Pleurotus biochemistry and molecular biology (4,8,20,(31)(32)(33)(34)42).Despite its economic importance, only a limited number of genetic studies of P. ostreatus have been done because of the difficulty in performing directed crosses between strains, contradictory data about the size and organization of its genetic material, and the lack of a genetic linkage map for it. Moreover, breeding of new P. ostreatus strains with a higher agricultural or industrial value has been traditionally carried out by trial and error because of the aforementioned reasons (2).…”