Ma Xiao-Kui, Ding Ning, Peterson Eric Charles, Daugulis Andrew J
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.
Industrial Microbiology, Universidad Icesi, Cl. 18 #122-135, Cali, Valle del Cauca, Colombia.
Appl Microbiol Biotechnol. 2016 Sep;100(17):7741-50. doi: 10.1007/s00253-016-7595-4. Epub 2016 May 13.
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.
多环芳烃（PAHs）与重金属（HMs）在污染土壤中同时存在的情况非常普遍，但重金属对多环芳烃生物修复过程中真菌 - 细菌协同作用的影响尚未得到研究。使用顶孢霉属P0997和枯草芽孢杆菌的共培养物对荧蒽污染的沙子进行生物修复，与纯细菌和纯真菌培养相比，降解率分别提高了109.4%和9.8%，总共去除了64.1±1.4%的荧蒽。Cu(2+)的存在将荧蒽去除率降低到53.7±1.7%，同时抑制细菌生长，并使细菌在真菌菌丝上的迁移率降低了49.5%。与不添加重金属的对照相比，Cu(2+)分别使细菌扩散系数D（整体随机运动扩散系数）和D eff（有效一维扩散系数）降低了46.8%和31.9%。然而，Mn(2+)使荧蒽降解率达到78.2±1.9%，提高了21.9%，同时促进细菌生长和细菌在真菌菌丝上的迁移，迁移率提高了12.0%，对D和D eff没有明显影响。因此，已证明重金属的存在会影响多环芳烃降解中的真菌 - 细菌协同作用，并且这种影响因重金属种类而异。
