title: Phenol degradation and genotypic analysis of dioxygenase genes in bacteria isolated from sediments.
abstract: The aerobic degradation of aromatic compounds by bacteria is performed by dioxygenases. To show some characteristic patterns of the dioxygenase genotype and its degradation specificities, twenty-nine gram-negative bacterial cultures were obtained from sediment contaminated with phenolic compounds in Wuhan, China. The isolates were phylogenetically diverse and belonged to 10 genera. All 29 gram-negative bacteria were able to utilize phenol, m-dihydroxybenzene and 2-hydroxybenzoic acid as the sole carbon sources, and members of the three primary genera Pseudomonas, Acinetobacter and Alcaligenes were able to grow in the presence of multiple monoaromatic compounds. PCR and DNA sequence analysis were used to detect dioxygenase genes coding for catechol 1,2-dioxygenase, catechol 2,3-dioxygenase and protocatechuate 3,4-dioxygenase. The results showed that there are 4 genotypes; most strains are either PNP (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is positive) or PNN (catechol 1,2-dioxygenase gene is positive, catechol 2,3-dioxygenase gene is negative, protocatechuate 3,4-dioxygenase gene is negative). The strains with two dioxygenase genes can usually grow on many more aromatic compounds than strains with one dioxygenase gene. Degradation experiments using a mixed culture representing four bacterial genotypes resulted in the rapid degradation of phenol. Determinations of substrate utilization and phenol degradation revealed their affiliations through dioxygenase genotype data.
authors.affiliation: South-Central University for Nationalities, College of Life Science, Wuhan, PR China.
authors.forename: Mengyang
authors.initials: M
authors.lastname: Tian
authors.affiliation: South-Central University for Nationalities, College of Chemistry and Materials, Wuhan, PR China.
authors.forename: Dongyun
authors.initials: D
authors.lastname: Du
authors.affiliation: South-Central University for Nationalities, College of Life Science, Wuhan, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.affiliation: South-Central University for Nationalities, College of Life Science, Wuhan, PR China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zeng
authors.affiliation: South-Central University for Nationalities, College of Life Science, Wuhan, PR China. Electronic address: chengguojun@mail.scuec.edu.cn.
authors.forename: Guojun
authors.initials: G
authors.lastname: Cheng
mesh_terms: D000150:Acinetobacter; D000421:Alcaligenes; D001711:Biotransformation; D002244:Carbon / Q000378:metabolism; D002681:China; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D049308:Dioxygenases / Q000235:genetics* / Q000378:metabolism*; D004787:Environmental Pollution; D019015:Geologic Sediments / Q000382:microbiology; D006090:Gram-Negative Bacteria / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D019800:Phenol / Q000378:metabolism*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011549:Pseudomonas; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012989:Soil Pollutants / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; D019800:Phenol; D002244:Carbon; D049308:Dioxygenases
keywords: Dioxygenase genes; Gram-negative bacteria; Isolation and identification; Phenol biodegradation; Substrate utilization