title: Isolation, identification and characterization of a glyphosate-degrading bacterium, Bacillus cereus CB4, from soil.
abstract: A bacterial strain named CB4, with highly effective glyphosate degradation capability, was isolated from soil after enrichment. On the basis of the Biolog omniLog identification system (Biolog) and 16S ribosomal RNA (rRNA) gene sequencing methods, strain CB4 was identified as Bacillus cereus. Further experiments were carried out to optimize the growth of strain CB4 and the glyphosate degradation activity by high performance liquid chromatography (HPLC). The optimal conditions were found as follows: initial pH 6.0, incubation temperature 35°C, glyphosate concentration 6 g L(-1), inoculation amount 5% and incubation time 5 days. Under the optimal conditions, stain CB4 utilized 94.47% of glyphosate. This is the first report on B. cereus with a capacity to utilize herbicide glyphosate, and it can degrade glyphosate concentrations up to 12 g L(-1). Metabolization of glyphosate by strain B. cereus CB4 was studied. Results indicated that two concurrent pathways were capable of degrading glyphosate to AMPA, glyoxylate, sarcosine, glycine and formaldehyde as products. Glyphosate breakdown in B. cereus CB4 was achieved by the C-P lyase activity and the glyphosate oxidoreductase activity.
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of Ministry Education, College of Life Sciences, Sichuan University, Chengdu, 610064, P.R. China.
authors.forename: Jieyu
authors.initials: J
authors.lastname: Fan
authors.forename: Guoxia
authors.initials: G
authors.lastname: Yang
authors.forename: Haoyu
authors.initials: H
authors.lastname: Zhao
authors.forename: Guanying
authors.initials: G
authors.lastname: Shi
authors.forename: Yucong
authors.initials: Y
authors.lastname: Geng
authors.forename: Taiping
authors.initials: T
authors.lastname: Hou
authors.forename: Ke
authors.initials: K
authors.lastname: Tao
mesh_terms: D001409:Bacillus cereus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D015373:Bacterial Typing Techniques; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005998:Glycine / Q000031:analogs & derivatives* / Q000378:metabolism; D006540:Herbicides / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013696:Temperature; D000097797:Glyphosate
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005998:Glycine; D006540:Herbicides; D012336:RNA, Ribosomal, 16S; D000097797:Glyphosate