title: Potential of Endophytic Bacterium Paenibacillus sp. PHE-3 Isolated from Plantago asiatica L. for Reduction of PAH Contamination in Plant Tissues.
abstract: Endophytes are ubiquitous in plants, and they may have a natural capacity to biodegrade polycyclic aromatic hydrocarbons (PAHs). In our study, a phenanthrene-degrading endophytic Paenibacillus sp. PHE-3 was isolated from P. asiatica L. grown in a PAH-contaminated site. The effects of environmental variables on phenanthrene biodegradation by strain PHE-3 were studied, and the ability of strain PHE-3 to use high molecular weight PAH (HMW-PAH) as a sole carbon source was also evaluated. Our results indicated that pH value of 4.0-8.0, temperature of 30 °C-42 °C, initial phenanthrene concentration less than 100 mg·L(-1), and some additional nutrients are favorable for the biodegradation of phenanthrene by strain PHE-3. The maximum biodegradation efficiency of phenanthrene was achieved at 99.9% after 84 h cultivation with additional glutamate. Moreover, the phenanthrene biodegradation by strain PHE-3 was positively correlated with the catechol 2,3-dioxygenase activity (ρ = 0.981, p < 0.05), suggesting that strain PHE-3 had the capability of degrading HMW-PAHs. In the presence of other 2-, 3-ringed PAHs, strain PHE-3 effectively degraded HMW-PAHs through co-metabolism. The results of this study are beneficial in that the re-colonization potential and PAH degradation performance of endophytic Paenibacillus sp. PHE-3 may be applied towards reducing PAH contamination in plants.
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. zhuxuezhu@njau.edu.cn.
authors.forename: Xuezhu
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. jinlinj0411@126.com.
authors.forename: Li
authors.initials: L
authors.lastname: Jin
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. 2013203015@njau.edu.cn.
authors.forename: Kai
authors.initials: K
authors.lastname: Sun
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. 2015103062@njau.edu.cn.
authors.forename: Shuang
authors.initials: S
authors.lastname: Li
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. lingwanting@njau.edu.cn.
authors.forename: Wanting
authors.initials: W
authors.lastname: Ling
authors.affiliation: Institute of Organic Contaminant Control and Soil Remediation, College of Resource and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. lixuel@njau.edu.cn.
authors.forename: Xuelin
authors.initials: X
authors.lastname: Li
mesh_terms: D018554:Avena / Q000382:microbiology; D001673:Biodegradation, Environmental; D002681:China; D060026:Endophytes / Q000502:physiology*; D056507:Paenibacillus / Q000502:physiology*; D010616:Phenanthrenes / Q000378:metabolism*; D010943:Plantago / Q000382:microbiology*; D006109:Poaceae / Q000382:microbiology*; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D017422:Sequence Analysis, DNA; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D010616:Phenanthrenes; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; C031181:phenanthrene
keywords: PAHs; biodegradation; catechol 2,3-dioxygenase; co-metabolism; endophytic bacterium; phenanthrene