Characterization of phenol degradation by Rhizobium sp. CCNWTB 701 isolated from Astragalus chrysopteru in mining tailing region.
To screen high strength phenol degrading bacteria, we selected 108 rhizobial strains isolated from nodules of eight wild legumes species in the mining tailing region of Shaanxi province, northwest of China, and cultivated them in a basal salt (BS) medium supplemented with different phenol concentrations as a sole carbon source. The results showed that some of the strains could use phenol as sole carbon source. In order to study the characteristics of phenol degradation, the strain CCNWTB701 isolated from Astragalus chrysopteru was used as well, due to the fact that it was very efficient in phenol degradation. The phenol degradation was around 99.5 and 78.3%, with an initial concentration of 900 and 1000 mg/l phenol in 62 and 66 h, respectively. Kinetic studies indicated that the strain had a high KS (743.1 microM) and an extremely high KSI (10,469 microM) in Haldane's model. The phylogenetic analysis based on 16S rRNA gene sequences showed that CCNWTB701 belonged to the Rhizobium genus, and it was closely related to Rhizobium mongolense and Rhizobium gallicum.
Wei
Gehong
G
College of Life Science, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A & F University, Yangling Shaanxi 712100, China. weigehong@yahoo.com.cn
Yu
Jianfu
J
Zhu
Yuhua
Y
Chen
Weimin
W
Wang
Li
L
D027883:Astragalus Plant / Q000382:microbiology*; D001673:Biodegradation, Environmental; D049109:Cell Proliferation; D004785:Environmental Pollutants / Q000378:metabolism*; D007220:Industrial Waste; D008906:Mining; D019800:Phenol / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012231:Rhizobium / Q000235:genetics / Q000378:metabolism* / Q000502:physiology
D004785:Environmental Pollutants; D007220:Industrial Waste; D012336:RNA, Ribosomal, 16S; D019800:Phenol