Metagenomic Analysis of Pulp and Paper Wastes and Prospects for Their Self-purification

Thousands of tons of waste accumulate, as a result of the activities of the pulp and paper industry, which is often stored in the form of dumps. However, intensifying the use of lignocellulose for more efficient bioremediation remains highly challenging. Therefore, the study of microbiomes with potentially desirable characteristics for the decomposition of pulp and paper wastes is currently an important task. In this study, a comprehensive assessment of the microbiota biodiversity of these dumps was carried out using high-throughput, high-resolution sequencing. In study 472 million high-quality clean reads assembled into 6,413,337 contigs with a total length of 4306 Mb, of which 3,633,174 open reading frames (ORFs) were identified. The core microbiome was composed of four phyla from Proteobacteria, Actinobacteria, Bacteroidetes, and Verrucomicrobia. Representatives of phylum Proteobacteria prevailed in samples. Annotation using the KEGG database in the Metabolism category resulted in 654,234 ORFs and 5138 ORFs encoding enzymes/proteins involved in degradation of lignocellulose which formed main pool of the wastes. By use of the created database, the search for lignocellulose degradation genes showed that genera Shewanella, Achromobacter, and Delftia covered significant part of the reads. The results indicate that the established microbiome of local landfills can be considered as an important source for improving lignocellulose bioremediation, provided that lignocellulosic fungi are sufficiently active. In whole, these new data can be used as a scientific basis to form an efficient eco-biotechnology for auto-remediation of pulp and paper industry waste.