title: Extracellular polymeric substances govern the development of biofilm and mass transfer of polycyclic aromatic hydrocarbons for improved biodegradation.
abstract: The hypothesis that extracellular polymeric substances (EPS) affect the formation of biofilms for subsequent enhanced biodegradation of polycyclic aromatic hydrocarbons was tested. Controlled formation of biofilms on humin particles and biodegradation of phenanthrene and pyrene were performed with bacteria and EPS-extracted bacteria of Micrococcus sp. PHE9 and Mycobacterium sp. NJS-P. Bacteria without EPS extraction developed biofilms on humin, in contrast the EPS-extracted bacteria could not attach to humin particles. In the subsequent biodegradation of phenanthrene and pyrene, the biodegradation rates by biofilms were significantly higher than those of EPS-extracted bacteria. Although, both the biofilms and EPS-extracted bacteria showed increases in EPS contents, only the EPS contents in biofilms displayed significant correlations with the biodegradation efficiencies of phenanthrene and pyrene. It is proposed that the bacterial-produced EPS was a key factor to mediate bacterial attachment to other surfaces and develop biofilms, thereby increasing the bioavailability of poorly soluble PAH for enhanced biodegradation.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Nanjing Normal University Center for Analysis and Testing, Nanjing 210046, China.
authors.forename: Yinping
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Nanjing Normal University Center for Analysis and Testing, Nanjing 210046, China.
authors.forename: Xiaoshu
authors.initials: X
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
authors.forename: Qiguo
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: jiangxin@issas.ac.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Jiang
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D001682:Biological Availability; D006812:Humic Substances / Q000382:microbiology; D008837:Micrococcus / Q000254:growth & development / Q000378:metabolism; D009161:Mycobacterium / Q000254:growth & development / Q000378:metabolism; D010616:Phenanthrenes / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism*; D011721:Pyrenes / Q000378:metabolism
chemical_list: D006812:Humic Substances; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D011108:Polymers; D011721:Pyrenes; C001861:humin; C031181:phenanthrene; C030984:pyrene
keywords: Biodegradation; Biofilms; Extracellular polymeric substances (EPS); Polycyclic aromatic hydrocarbons (PAHs)