One Belongs To The Pure Culture Of The Candidate Gate Op10 Strain Gsoil348 Whole-genome Sequencing

As a consequence of the rapid development of genomics and DNA sequencing technology, whole genome sequence of microorganisms now is becoming more and more common and efficient. Currently, a large amount of genomes are sequenced and available in public databases. However, the phylum representatives of these genomes are highly skewed in databases, several bacterial phyla such as Proteobacteria and Firmucutes contained much more genome compared with other phyla which poorly understood or barely studied, just like Candidate phylum OP10.Based on the pure culture of bacterial strain GSoil348, which belongs to the candidate phylum OP10, this study sequenced the whole genome of this isolate, and investigated the characteristic of it from the phylogenetic and physiological view. The evolutionary status and distribution of GSoil348 as well as Candidate phylum OP10 in different environments are also discussed.The genome of GSoil348 is composed by a circular chromosome of 5,231,762 bp and a prophage of 45,503 bp, harbouring 5555 and 58 ORFs, respectively. The prophage is existed both on and outside chromosome. Average length of ORFs is 847 bp. The phylogenetic analysis of 16S rRNA gene indicated that GSoil348 belongs to Candidate OP10 group 1, and the additional multiple ribosomal proteins based phylogenetic tree displayed a clear affinity between OP10 and Actinobacteria. After compared GSoil348 and metagenomic ORFs in public database, a wide range of distribution of OP10 closed proteins was identified, including open ocean with the water depth between 0 and more than 5000 m or habitats with the temperature between 0 and more than 40℃and salinity between 0 and more than 60 psu. However, the numbers of ORFs in different environments are unbalanced. Generally, most of them have been found in aerobic and warmer than 20℃habitats.The analysis of metabolic pathways showed a distinct adaptability of GSoil348 to oligotrophic environment. Low ability of organic carbon source catabolism and integrated synthetic pathways of amino acid, purine and pyridine were identified. Only four types of organic carbon souces can be utilized by GSoil348, including xylose, fucose, rhamnose and pyruvate. Compared with other heterophytic bacteria, GSoil348 encoding less ABC transporters and less two-component system proteins. Interestingly, two key enzymes, cphl and rcpl, which belong to a cyanobacterial phytochrome two-component light sensory system were identified in GSoil348's transcriptome. And GSoil348 also contains relative completed pathway in carbon fixation in photosynthetic organisms. This finding implied that GSoil348 or even other members in Candidate phylum OP10 may be able to perform partial photosynthesis.