title: Heavy metals species affect fungal-bacterial synergism during the bioremediation of fluoranthene.
abstract: The co-occurrence of polycyclic aromatic hydrocarbons (PAHs) with heavy metals (HMs) is very common in contaminated soils, but the influence of HMs on fungal-bacterial synergism during PAH bioremediation has not been investigated. The bioremediation of fluoranthene-contaminated sand using co-cultures of Acremonium sp. P0997 and Bacillus subtilis showed increases of 109.4 and 9.8 % in degradation compared to pure bacterial and fungal cultures, respectively, removing 64.1 ± 1.4 % fluoanthene in total. The presence of Cu(2+) reduced fluoranthene removal to 53.7 ± 1.7 %, while inhibiting bacterial growth, and reducing translocation of bacteria on fungal hyphae by 49.5 %, in terms of the bacterial translocation ratio. Cu(2+) reduced bacterial diffusion by 46.8 and 31.9 %, as reflected by D (a bulk random motility diffusional coefficient) and D eff (the effective one-dimensional diffusion coefficient) compared to the control without HM supplementation, respectively. However, Mn(2+) resulted in a 78.2 ± 1.9 % fluoranthene degradation, representing an increase of 21.9 %, while enhancing bacterial growth and bacterial translocation on fungal hyphae, showing a 12.0 % increase in translocation ratio, with no observable impact on D and D eff. Hence, the presence of HMs has been shown to affect fungal-bacterial synergism in PAH degradation, and this effect differs with HM species.
authors.affiliation: Key Laboratory of Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Developing of Endangered Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University, Xi'an, 710055, Shaanxi, People's Republic of China. biomarkuis@gmail.com.
authors.forename: Xiao-Kui
authors.initials: XK
authors.lastname: Ma
authors.affiliation: Key Laboratory of Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Developing of Endangered Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University, Xi'an, 710055, Shaanxi, People's Republic of China.
authors.forename: Ning
authors.initials: N
authors.lastname: Ding
authors.affiliation: Industrial Microbiology, Universidad Icesi, Cl. 18 #122-135, Cali, Valle del Cauca, Colombia.
authors.forename: Eric Charles
authors.initials: EC
authors.lastname: Peterson
authors.affiliation: Department of Chemical Engineering, Queen's University, K7L 3N6, Kingston, ON, Canada.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Daugulis
mesh_terms: D000164:Acremonium / Q000378:metabolism*; D001412:Bacillus subtilis / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018920:Coculture Techniques; D004787:Environmental Pollution; D005449:Fluorenes / Q000378:metabolism*; D019216:Metals, Heavy / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013559:Symbiosis / Q000502:physiology
chemical_list: D005449:Fluorenes; D019216:Metals, Heavy; D012989:Soil Pollutants; C007738:fluoranthene
keywords: Bacterial movement; Bioremediation; Fungal highway; Fungal-bacterial synergism; Heavy metals species