Complete genome sequence of Polynucleobacter necessarius subsp. asymbioticus type strain (QLW-P1DMWA-1T)

Standards in Genomic Sciences (Impact Factor: 3.17). 03/2012; 6(1):74-83. DOI: 10.4056/sigs.2395367
Source: PubMed


Polynucleobacter necessarius subsp. asymbioticus strain QLW-P1DMWA-1(T) is a planktonic freshwater bacterium affiliated with the family Burkholderiaceae (class Betaproteobacteria). This strain is of interest because it represents a subspecies with cosmopolitan and ubiquitous distribution in standing freshwater systems. The 16S-23S ITS genotype represented by the sequenced strain comprised on average more than 10% of bacterioplankton in its home habitat. While all strains of the subspecies P. necessarius asymbioticus are free-living freshwater bacteria, strains belonging to the only other subspecies, P. necessarius subsp. necessarius are obligate endosymbionts of the ciliate Euplotes aediculatus. The two subspecies of P. necessarius are the instances of two closely related subspecies that differ in their lifestyle (free-living vs. obligate endosymbiont), and they are the only members of the genus Polynucleobacter with completely sequenced genomes. Here we describe the features of P. necessarius subsp. asymbioticus, together with the complete genome sequence and annotation. The 2,159,490 bp long chromosome with a total of 2,088 protein-coding and 48 RNA genes is the first completed genome sequence of the genus Polynucleobacter to be published and was sequenced as part of the DOE Joint Genome Institute Community Sequencing Program 2006.

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Available from: Qinglong L Wu
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    • "The investigated F10 lineage population has been monitored from 2003 and is currently represented by a total of twelve cultivated strains obtained from Pond-1 over a period of four years. One of these strains was genome-sequenced by the DOE Joint Genome Institute, and an ecological interpretation of its genome is presented here; the description of sequencing and annotation, as well as a basic characterization of the genome, has been presented elsewhere [22]. "
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