Deciphering the bacterial microbiome in response to long-term mercury contaminated soil

An aerobic, Gram-negative bacterial strain, designated CTN-1T, capable of degrading chlorothalonil was isolated from a long-term chlorothalonil-contaminated soil in China, and was subjected to a polyphasic taxonomic investigation. Strain CTN-1T grew at 15–37 °C (optimum 28–30 °C) and at pH 6.0–9.0 (optimum pH 7.0–7.5). The G+C content of the total DNA was 67.1 mol%. Based on 16S rRNA gene sequence analysis, strain CTN-1T was related most closely to Lysobacter daejeonensis DSM 17634T (97.1 % similarity), L. soli DCY21T (95.7 %), L. concretionis Ko07T (95.5 %), L. gummosus LMG 8763T (95.3 %) and L. niastensis DSM 18481T (95.2 %). The novel strain showed less than 95.0 % 16S rRNA gene sequence similarity to the type strains of other Lysobacter species. The major cellular fatty acids of strain CNT-1T were iso-C16 : 0 (23.0 %), iso-C15 : 0 (21.4 %) and iso-C17 : 1 ω9c (15.3 %). The major isoprenoid quinone was Q-8 (99 %), and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. These chemotaxonomic data supported the affiliation of strain CTN-1T to the genus Lysobacter. Levels of DNA–DNA relatedness between strain CTN-1T and L. daejeonensis DSM 17634T were 34.6–36.1 %. Phylogenetic analysis based on 16S rRNA gene sequences, DNA–DNA hybridization data and biochemical and physiological characteristics strongly supported the genotypic and phenotypic differentiation of strain CTN-1T from recognized species of the genus Lysobacter. Strain CTN-1T is therefore considered to represent a novel species of the genus Lysobacter, for which the name Lysobacter ruishenii sp. nov. is proposed. The type strain is CTN-1T (=DSM 22393T =CGMCC 1.10136T).

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Olivibacter jilunii sp. nov., isolated from DDT-contaminated soil

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.042416-0 ◽

2013 ◽

Vol 63 (Pt_3) ◽

pp. 1083-1088 ◽

Cited By ~ 11

Author(s):

Kai Chen ◽

Shu-Kun Tang ◽

Guang-Li Wang ◽

Guo-Xing Nie ◽

Qin-Fen Li ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Contaminated Soil ◽

Type Species ◽

Rrna Gene ◽

Content Type ◽

Link Type ◽

The Family ◽

The 16S Rrna Gene

Bacterial strain 14-2AT, isolated from a long-term DDT-contaminated soil in China, was characterized by using a polyphasic approach to clarify its taxonomic position. Strain 14-2AT was found to be Gram-negative, aerobic, non-spore-forming, non-motile, non-flagellated and rod-shaped. The new isolate was able to grow at 4–42 °C, pH 6.0–9.0 and with 0–5 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the family Sphingobacteriaceae . The 16S rRNA gene sequence of strain 14-2AT showed the highest similarity with Olivibacter oleidegradans TBF2/20.2T (99.4 %), followed by Pseudosphingobacterium domesticum DC-186T (93.8 %), Olivibacter ginsengisoli Gsoil 060T (93.6 %), Olivibacter terrae Jip13T (93.1 %), Olivibacter soli Gsoil 034T (92.8 %) and Olivibacter sitiensis AW-6T (89.6 %). The DNA–DNA hybridization value between strains 14-2AT and O. oleidegradans TBF2/20.2T was 34.45±2.11 %. Strain 14-2AT contained phosphatidylethanolamine, phosphatidylmonomethylethanolamine, aminophospholipid and phosphatidylinositol mannoside as the major polar lipids. The DNA G+C content was 41.2 mol%. MK-7 is the major isoprenoid quinone. Summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0 and iso-C17 : 0 3-OH are the major fatty acids. The phenotypic and chemotaxonomic data confirmed the affiliation of strain 14-2AT to the genus Olivibacter . On the basis of the phylogenetic and phenotypic characteristics, and chemotaxonomic data, strain 14-2AT is considered to represent a novel species of the genus Olivibacter , for which the name Olivibacter jilunii sp. nov. is proposed; the type strain is 14-2AT ( = KCTC 23098T = CCTCC AB 2010105T).

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