Iwasaki Akio, Takagi Kazuhiro, Yoshioka Yuichi, Fujii Kunihiko, Kojima Yuki, Harada Naoki
Kowa Research Institute, Kowa Co., Ltd, 1-25-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
Pest Manag Sci. 2007 Mar;63(3):261-8. doi: 10.1002/ps.1334.
A moderately persistent herbicide, simazine, has been used globally and detected as a contaminant in soil and water. The authors have isolated a simazine-degrading bacterium from a simazine-degrading bacterial consortium that was enriched using charcoal as a microhabitat. The isolate, strain CDB21, was gram-negative, rod-shaped (0.5-0.6 microm x 1.0-1.2 microm) and motile by means of a single polar flagellum. Based on 16S rRNA sequence analysis, strain CDB21 was identified as a novel beta-proteobacterium exhibiting 100% sequence identity with the uncultured bacterium HOClCi25 (GenBank accession number AY328574). PCR using primers that were specific for the genes of the atrazine-degrading enzymes (atzABCDEF) of Pseudomonas sp. strain ADP showed that strain CDB21 also possessed the entire set of genes of these enzymes. Nucleotide sequences of the atzCDEF genes of strain CDB21 were 100% identical to those of Pseudomonas sp. strain ADP. Sequence identity of the atzA genes between these bacteria was 99.7%. The 398-nucleotide upstream fragment of the atzB gene of strain CDB21 was 100% identical to ORF30 of Pseudomonas sp. strain ADP, and the 1526-nucleotide downstream fragment showed 99.8% sequence similarity to the atzB gene of the pseudomonad.
西玛津是一种具有中等持久性的除草剂，已在全球范围内使用，并在土壤和水中被检测为污染物。作者从一个以木炭为微生境富集培养的西玛津降解细菌群落中分离出了一株西玛津降解菌。该分离菌株CDB21为革兰氏阴性菌，呈杆状（0.5 - 0.6微米×1.0 - 1.2微米），借助一根单极鞭毛运动。基于16S rRNA序列分析，菌株CDB21被鉴定为一种新型β-变形菌，与未培养细菌HOClCi25（GenBank登录号AY328574）的序列同一性为100%。使用针对假单胞菌属菌株ADP的阿特拉津降解酶（atzABCDEF）基因的特异性引物进行PCR检测表明，菌株CDB21也拥有这些酶的全套基因。菌株CDB21的atzCDEF基因的核苷酸序列与假单胞菌属菌株ADP的完全相同。这些细菌之间atzA基因的序列同一性为99.7%。菌株CDB21的atzB基因398个核苷酸的上游片段与假单胞菌属菌株ADP的ORF30完全相同，1526个核苷酸的下游片段与该假单胞菌的atzB基因的序列相似性为99.8%。
