Mutual interactions of Pleurotus ostreatus with bacteria of activated sludge in solid-bed bioreactors

• Published in: World journal of microbiology & biotechnology 2016-06, Vol.32 (6), p.94-14, Article 94
• Main Authors: Svobodová, Kateřina, Petráčková, Denisa, Kozická, Barbora, Halada, Petr, Novotný, Čeněk
• Format: Article
• Language: English
• Subjects: Activated sludge; Analysis; Applied Microbiology; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - growth & development; Bacteria - metabolism; Batch Cell Culture Techniques; Batch reactors; Biochemistry; Biodegradation; Biomedical and Life Sciences; Bioreactors; Bioreactors - microbiology; Bioremediation; Biosynthesis; Biotechnology; Carbon - metabolism; Coenzyme A Ligases - metabolism; Culture; Culture media; Decoloring; DNA, Bacterial - analysis; DNA, Ribosomal - analysis; Down-Regulation; Dyes; Environmental Engineering/Biotechnology; Enzyme Activation; Enzymes; Experiments; Fungal Proteins - analysis; Fungi; Genotype; Glucose; Kinases; Laboratories; Laccase - metabolism; Life Sciences; Membrane reactors; Metabolites; Microbial Interactions; Microbial Viability; Microbiology; Microorganisms; Original Paper; Phenotype; Pleurotus - enzymology; Pleurotus - metabolism; Pleurotus - physiology; Pleurotus ostreatus; Pollutants; Reactors; Rhodococcus; Rhodococcus - enzymology; Rhodococcus - growth & development; Rhodococcus - metabolism; Rhodococcus erythropolis; RNA, Ribosomal, 16S - genetics; Sewage - microbiology; Sludge; Stresses; Studies; Waste Water - microbiology; Xenobiotics
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-016-2050-3

White rot fungi are well known for their ability to degrade xenobiotics in pure cultures but few studies focus on their performance under bacterial stress in real wastewaters. This study investigated mutual interactions in co-cultures of Pleurotus ostreatus and activated sludge microbes in batch reactors and different culture media. Under the bacterial stress an increase in the dye decolorization efficiency (95 vs. 77.1 %) and a 2-fold elevated laccase activity (156.7 vs. 78.4 Ul −1 ) were observed in fungal-bacterial cultures compared to pure P. ostreatus despite a limited growth of bacteria in mixed cultures. According to 16S-rDNA analyses, P. ostreatus was able to alter the structure of bacterial communities. In malt extract-glucose medium the fungus inhibited growth of planktonic bacteria and prevented shifts in bacterial utilization of potential C-sources. A model bacterium, Rhodococcus erythropolis responded to fungal metabolites by down regulation of uridylate kinase and acetyl-CoA synthetase. Graphical Abstract