Determination of Potential Producers of Biogenic Magnetic Nanoparticles Among the Fungi Representatives of Ascomycota and Basidiomycota Divisions

Abstract

Background. Biogenic magnetic nanoparticles (BMNs) were found in organisms that belong to all three domains: prokaryotes, archaea, and eukaryotes. And it was found that the mechanism of biomineralization of BMN is the same for all living organisms. BMNs have been experimentally detected in algae and protozoa, worms, сhitons, snails, ants and butterflies, honey bees, termites, lobsters, tritons, migratory and non-migratory fish, turtles, birds, bats, dolphins and whales, humans, plants and mushrooms. The study of the presence of BMNs in representatives of the kingdom of the Fungi is not numerous, as well as an idea of the functions they perform. In particular, a small amount of bioinformatic research was caused by the absence of decrypted fungi genomes in databases. In total, there are 10 divisions of the kingdom Fungi, of which not a single division has been analyzed completely. The study of fungi, which are representatives of different parts of the kingdom Fungi has fundamental and practical interest. From a fundamental point of view, identifying potential producers of BMNs among fungi can help find an answer to an open-ended question about the functional purpose of BMNs in various organisms. From a practical point of view, the identification of potential producers of BMNs among fungi is promising for the manufacture of magnetically controlled sorbent based on the biomass of fungi. Two of the most abundant sections of fungi – Ascomycetes (Ascomycota) and Basidiomycetes (Basidiomycota), which genomes are widely represented in bioinformatic databases were selected to the study.Objective. The aim of the is to identify potential producers of BMNs among the representatives of higher fungi by methods of comparative genomics and experimental research using atomic force microscopy (AFM) and magnetic force microscopy (MFM) of samples of higher fungi tissue for the presence of BMN in them.Methods. The method of pairwise alignment of the amino acid sequences of the fungi proteins with Magnetospirillum gryphiswaldense MSR-1 proteins by using BLAST program of National Center for Biotechnology Information (NCBI, USA). Methods for AFM and MFM were used to study the fruiting bodies of fungi for the presence of BMNs.Results. Bioinformatic analysis of 160 species of fungi of the Ascomycota division and 63 species of fungi of the Basidiomycota division was carried out and selected to analyze the alignment results for 15 representatives each, since their genome was deciphered by more than 50% in the database of the GenBank NCBI and functions of homologous proteins are known. For the analysis of the conducted research results, the following indicators were used: the value of the E-number (the number of alignments with the same or better alignment weight that can be found by chance in a database of a certain size), Іdent – the percentage of amino acid sequence overlapping within which the alignment is made, Length – the number of identical amino acid residues of the proteins, compared at optimal alignment and the function of the aligned proteins. When Ident > 18%, E-number ≤ 0.05, Length > 100, it can be argued that the sequences are homologous, and the fungus is a potential producer of BMN.Conclusions. Using the methods of comparative genomics, it is shown that among the studied representatives of higher fungi of the Ascomycota and Basidiomycota division, which genomes are decoded by more than 50% in the GenBank NCBI database, all species are potential producers of BMNs. At the same time, experimental studies of BMNs in A. bisporus and L. edodes fungi using the methods of AFM and MSM showed that BMNs in fungi form chains localized on the walls of the hyphae of the investigated fungi samples.