title: Kinetics of PAH degradation by a new acid-metal-tolerant Trabulsiella isolated from the MGP site soil and identification of its potential to fix nitrogen and solubilize phosphorous.
abstract: Development of an efficient bioinoculum is considered as an appropriate remedial approach to treat the PAHs-metal mixed contaminated sites. Therefore, we aimed to isolate a degrader able to exert an outstanding PAH catabolic potential with added traits of pH-metal-resistance, N-fix or P-solubilization from a manufactured gas plant site soil. The identified strain (MTS-6) was a first low and high molecular weight (LMW and HMW) PAHs degrading Trabulsiella sp. tolerant to pH 5. MTS-6 completely degraded the model 3 [150mgL(-1) phenanthrene (Phe)], 4 [150mgL(-1) pyrene (Pyr)] and 5 [50mgL(-1) benzo[a]pyrene (BaP)] ring PAHs in 6, 25 and 90 days, respectively. Presence of co-substrate (100mgL(-1) Phe) increased the biodegradation rate constant (k) and decreased the half-life time (t1/2) of HMW PAHs (100mgL(-1) Pyr or 50mgL(-1) BaP). The strain fixed 47μgmL(-1)N and solubilized 58μgmL(-1)P during PAH metabolism and exhibited an EC50 value of 3-4mgL(-1) for Cu, Cd, Pb and Zn. Over 6mgL(-1) metal levels was lethal for the microbe. The identified bacterium (MTS-6) with exceptional multi-functional traits opens the way for its exploitation in the bioremediation of manufactured gas plant sites in a sustainable way by employing bioaugmentation strategy.
authors.affiliation: Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 660-701, South Korea; Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), PO Box 486, Salisbury South, SA 5106, Australia. Electronic address: saran.miles2go@gmail.com.
authors.forename: Saranya
authors.initials: S
authors.lastname: Kuppusamy
authors.affiliation: Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), PO Box 486, Salisbury South, SA 5106, Australia; Global Centre for Environmental Remediation (GCER), Faculty of Science and Information Technology, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Palanisami
authors.initials: P
authors.lastname: Thavamani
authors.affiliation: Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), PO Box 486, Salisbury South, SA 5106, Australia; Global Centre for Environmental Remediation (GCER), Faculty of Science and Information Technology, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Mallavarapu
authors.initials: M
authors.lastname: Megharaj
authors.affiliation: Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 660-701, South Korea.
authors.forename: Yong Bok
authors.initials: YB
authors.lastname: Lee
authors.affiliation: Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environment (CRC CARE), PO Box 486, Salisbury South, SA 5106, Australia; Global Centre for Environmental Remediation (GCER), Faculty of Science and Information Technology, The University of Newcastle, Callaghan, NSW 2308, Australia.
authors.forename: Ravi
authors.initials: R
authors.lastname: Naidu
mesh_terms: D001673:Biodegradation, Environmental; D004755:Enterobacteriaceae / Q000187:drug effects / Q000378:metabolism*; D019652:Extraction and Processing Industry; D005579:Fossil Fuels; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D019216:Metals, Heavy / Q000633:toxicity; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism* / Q000633:toxicity
chemical_list: D005579:Fossil Fuels; D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D010758:Phosphorus; D009584:Nitrogen
keywords: Diazotrophic bacteria; HMW PAHs degradation; Heavy metal resistance; Mixed contamination; Phosphate solubilizer